MUD\WTR by MUD\WTR

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Allergic rhinitis (hay fever). Although there has been interest in using oral black pepper for allergic rhinitis, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Asthma. Although there has been interest in using oral black pepper for asthma, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Athletic performance. Oral black pepper has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: One small clinical trial in untrained males shows that taking a supplement containing black pepper extract 10 mg, caffeine 400 mg, capsicum extract 66.7 mg, and niacin 40 mg as a single dose prior to exercise does not improve strength, time to exhaustion, or maximal oxygen consumption when compared with placebo (37873).
• Depression. Although there has been interest in using oral black pepper for depression, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Diarrhea. Although there has been interest in using oral black pepper for diarrhea, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Dysmenorrhea. Although there has been interest in using oral black pepper for dysmenorrhea, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Dyspepsia. Although there has been interest in using oral black pepper for dyspepsia, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Fall prevention. It is unclear if inhaling black pepper oil as aromatherapy is beneficial for fall prevention in older adults. Details: One small clinical study in older adults shows that applying black pepper oil near the right side of the nose as an olfactory stimulant improves stability while the eyes are closed during a one-minute trial when compared with the application of water. The improvement with black pepper oil is comparable to the improvement seen with the application of lavender oil (29160). It is unclear if any benefit persists after inhalation of black pepper oil.
• Fatigue. It is unclear if oral black pepper is beneficial in patients with fatigue. Details: One small clinical trial in adults with below-average energy levels shows that taking black pepper 2 grams as a single dose does not improve sustained attention, motivation to perform cognitive tasks, or feelings of mental energy and mental fatigue when compared with placebo (91731).
• Flatulence. Although there has been interest in using oral black pepper for flatulence, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Headache. Although there has been interest in using oral black pepper for headache, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Insect bite. Topical black pepper has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: One small clinical trial shows that applying a specific product (Trikatu) containing black pepper, long pepper, and ginger, as well as camphor, eucalyptus oil, and menthol, directly to mosquito bites does not reduce papule size, erythema, edema, or pruritis when compared with a control compound containing the same base ingredients but without the pepper and ginger components (89893).
• Obesity. Although there has been interest in using oral black pepper for obesity, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Pain (chronic). Although there has been interest in using topical black pepper for chronic pain related to various etiologies, including osteoarthritis, postherpetic neuralgia, and peripheral neuropathy, there is insufficient reliable information about the clinical effects of black pepper for these conditions.
• Rhinosinusitis. Although there has been interest in using oral black pepper for rhinosinusitis, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Sexual desire. Although there has been interest in using oral black pepper for increasing sexual desire, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Smoking cessation. It is unclear if inhaling black pepper essential oil as aromatherapy is effective for smoking cessation. Details: One small clinical trial in adult male smokers who were deprived from smoking overnight shows that inhaling a vapor from the essential oil of black pepper, as needed over a 3-hour period, reduces cigarette cravings, negative feelings, and anxiety when compared with a placebo vapor (29159). Another small clinical study in patients addicted to dipping, chewing, or smoking tobacco shows that placing a drop of black pepper essential oil on tissue paper and inhaling for 2 minutes at least three times a day for 3 days reduces nicotine cravings when compared to baseline (90502).
• Swallowing dysfunction. It is unclear if inhaling black pepper oil as aromatherapy is beneficial in patients with swallowing dysfunction. Details: One small clinical study in post-stroke residents of nursing homes shows that one minute of olfactory stimulation with black pepper oil before each meal for 30 days decreases swallowing reflex latency by 11 seconds and increases the number of swallowing movements by 3.3 when compared to baseline (29161). A small clinical trial in children with neurological disorders who were on long-term enteral nutrition shows that applying black pepper oil to the nostrils or nasal cavity for one minute improves the amount of oral intake and swallowing movement in 63% of patients. Although oral intake increased, the need for enteral nutrition was not eliminated (29162).
• Vitiligo. It is unclear if topical piperine oil, a constituent of black pepper, is beneficial in patients with vitiligo. Details: A small clinical study in patients with vitiligo shows that applying piperine oil 1% daily in addition to receiving narrowband ultraviolet B (NB-UVB) light therapy every other day for 3 months improves repigmentation more rapidly when compared with using NB-UVB alone (103820). More evidence is needed to rate black pepper for these uses.

(Read more about BLACK PEPPER)

LIKELY EFFECTIVE

• Mental alertness. Consumption of black tea can improve or prevent declines in mental alertness, attention, and cognitive capacity. Details: Preliminary clinical research in healthy people shows that consumption of black tea containing caffeine 30-100 mg, as well as other caffeinated beverages, throughout the day prevents a decline in alertness and cognitive capacity when compared with placebo (4221,4224,92404). Also, some preliminary clinical research in healthy people shows black tea can improve attention. The effect may be dose-dependent, with greater effects observed in patients consuming black tea that contains higher concentrations of caffeine and theanine (92404). Caffeine can improve mental performance and alertness following prolonged sleep deprivation (10205). Combining caffeine with taurine seems to provide a small improvement in mental performance (9899). Combining caffeine with glucose as an "energy drink" seems to improve mental performance when compared with placebo or either caffeine or glucose alone (13732).

POSSIBLY EFFECTIVE

• Hypotension. Consumption of black tea seems to increase blood pressure in older patients with postprandial hypotension. Details: Several clinical studies in older adults with postprandial hypotension show that drinking caffeinated beverages such as black tea seems to increase blood pressure in the short-term when compared with placebo or not drinking caffeinated beverages (11834,11835).
• Myocardial infarction (MI). Consumption of black tea seems to be associated with a reduced risk of MI. Details: There is some evidence that people who consume at least one cup of black tea daily have a lower risk of MI when compared with not drinking tea (4222,8119,8121). Consuming black tea for at least one year before a heart attack also seems to be associated with a 28% to 44% reduced risk of subsequent death when compared with not drinking tea (8120).
• Osteoporosis. Consumption of black tea seems to have beneficial effects on bone health. Details: Population research suggests that consuming black tea is associated with increased bone mineral density, especially in older females aged 65-76 years and those whose habitual tea consumption extends beyond 10 years, when compared with not drinking tea (6404,8116). Black tea consumption also seems to be associated with a lower risk of hip fracture in adults aged 50 years or more (10949,15014).
• Ovarian cancer. Consumption of black tea seems to be associated with a reduced risk of ovarian cancer. Details: Adults who regularly consume tea, including black tea or green tea, appear to have a significantly lower risk of developing ovarian cancer when compared with those who never or seldom consume tea (9228,13208). In one prospective population study, adults who consume at least 2 cups of tea daily have a 46% lower risk of ovarian cancer when compared with those who do not regularly consume tea (13208).
• Parkinson disease. Consumption of black tea seems to be associated with a reduced risk of Parkinson disease.
• Parkinson disease. For males, the effects seem to be dose related. For example, males consuming 421-2716 mg of total caffeine (equivalent to 5-33 cups of black tea) from any source daily seem to have the greatest reduction in risk. However, there seems to be a significant reduction in risk even with consumption of as little as 124-208 mg of total caffeine (equivalent to 1-3 cups of black tea) daily (6022). In females, the effects do not seem to be dose related. Moderate consumption of caffeine (equivalent to 1-4 cups black tea daily) seems to provide the most reduction in risk (1238). Also, drinking tea appears to be associated with a reduced incidence of Parkinson disease among people who smoke when compared with almost never drinking tea (9236).

POSSIBLY INEFFECTIVE

• Bladder cancer. Consumption of black tea does not seem to be associated with a reduced risk of urinary tract cancers, including bladder cancer. Details: Observational research has found that drinking tea, including black and green tea, is not associated with a reduced risk of urinary tract cancers, including bladder cancer, when compared with those who almost never drink black tea (36482,36561).
• Breast cancer. Consumption of black tea does not seem to be associated with a reduced risk of breast cancer. Details: Observational research has found that drinking black tea is not associated with a lower risk of breast cancer when compared with not drinking black tea (9235,92406).
• Colorectal cancer. Consumption of black tea does not seem to be associated with a reduced risk of colorectal cancer. Details: Some population research has found that drinking tea, including black tea or green tea, might be associated with a reduced risk of colorectal cancer when compared with little or no tea consumption (9234,36535). However, most research has found that drinking tea is not associated with a reduced risk of colorectal cancer (9222,9223,9234,36385,36416,36474,36535,36553,36582). Additionally, some population research has found that increased consumption of black tea is associated with an increased risk of colorectal cancer when compared with those who almost never drink black tea (8041,36482).
• Diabetes. Consumption of black tea does not seem to be associated with a reduced risk of diabetes and does not seem to improve glycemic control in patients with diabetes. Details: Preliminary clinical research in patients with diabetes shows that taking an extract of black and green tea daily for 3 months does not reduce glycated hemoglobin (HbA1C) when compared with placebo (36434). Additionally, population research in Japanese adults has found that drinking at least 1 cup of black tea daily does not seem to be associated with a lower risk of developing type 2 diabetes when compared with drinking less than 1 cup daily (14313).
• Endometrial cancer. Consumption of black tea does not seem to be associated with a reduced risk of endometrial cancer. Details: A meta-analysis of results from population research has found that increasing black tea intake by 1 cup per day is not associated with a reduced risk of endometrial cancer when compare with no or low black tea consumption (92409).
• Esophageal cancer. Consumption of black tea does not seem to be associated with a reduced risk of esophageal cancer. Details: A meta-analysis of results from population research has found that people who drink higher amounts of black tea do not have a reduced risk of esophageal cancer when compared with those who drink lesser amounts (90186). However, some population research has found that drinking large amounts of strong black tea is associated with a two-fold INCREASED risk for esophageal cancer when compared with people who drink less black tea (102756).
• Gastric cancer. Consumption of black tea does not seem to be associated with a reduced risk of gastric cancer. Details: While some epidemiological evidence has found that increased consumption of tea, including black or green tea, is associated with a reduced risk of stomach cancer (36561), most evidence shows that drinking tea is not associated with a reduced stomach cancer risk (9222,9223,36553,36333). Additionally, some epidemiological evidence has found that consumption of tea may be associated with an increased risk of mortality due to stomach cancer when compared with nonregular tea consumption (36474).
• Lung cancer. Consumption of black tea does not seem to be associated with a reduced risk of lung cancer. Details: Most population research found that drinking up to 5 cups of black tea daily is not associated with reduced risk of lung cancer (36474,36553,90177,97128). One population study even found an increase in risk of lung cancer associated with tea consumption, including black and green tea, when compared with nonregular tea consumption. However, this study did not adjust for the patients' baseline smoking status and carcinogen exposure (36474).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Atherosclerosis. Consumption of black tea seems to be associated with a reduced risk of severe, but not mild or moderate, aortic atherosclerosis. Details: Epidemiological research has found that increased intake of brewed black tea (125-500 mL or 1-4 cups) is associated with a reduced risk of severe aortic atherosclerosis, especially in females. However, black tea intake is not associated with a reduced risk of mild or moderate aortic atherosclerosis (3450).
• Cardiovascular disease (CVD). Consumption of black tea may be associated with a modest reduction in CVD-related mortality. Details: A prospective cohort study of nearly 500,000 adults 40-69 years of age in the United Kingdom Biobank shows that black tea intake in quantities greater than 1 cup daily is associated with a modestly reduced rate of CVD-related mortality over a mean follow-up of about 11 years. Consuming anywhere between 2-9 cups of black tea daily resulted in similar hazard ratios; consuming 10 or more cups per day may be associated with a further reduction in risk (108970).
• Chronic obstructive pulmonary disease (COPD). It is unclear if black tea is associated with a reduced risk of COPD. Details: One prospective, observational study in older adults has found that consumption of at least 3 cups daily of tea, including black tea, oolong tea, and green tea, is associated with a 23% reduced risk of COPD prevalence and a 65% reduced risk of developing COPD in models adjusted for potential confounders when compared with the lowest tea consumption (107201).
• Coronary heart disease (CHD). It is unclear if black tea is associated with a reduced risk of CHD or CHD-related mortality. Details: Although a meta-analysis of population research found that general tea consumption might protect against cardiovascular disease (CVD) or death from CVD, a sub-group analysis has found that drinking black tea does not seem to offer protection (102728). In fact, some individual population research found that black tea consumption is associated with an increased incidence of CHD progression and CHD mortality in those with existing CHD (220,36339). In contrast, observational research in healthy adults has found that those who drink black tea regularly have a decreased risk of developing CHD (7726,36363,36391,36420).
• Dementia. It is unclear if black tea, consumed in conjunction with coffee, is associated with a reduced risk of dementia. Details: A prospective, observational study suggests consumption of tea, including black tea, of at least 4 cups with 0.5-1 cups of coffee daily is associated with a 30% reduced risk of dementia when compared with not drinking tea or coffee. Also, drinking 2-3 cups daily of both tea and coffee is associated with a 28% reduced risk of dementia stroke when compared with not drinking tea and coffee (107204).
• Depression. It is unclear if black tea is associated with a reduced risk of depression. Details: Observational research in healthy adult office workers without a history of anxiety or depression has found that consumption of at least 1-4 cups daily of black tea, as well as caffeine from other sources, is associated with a 41% to 61% reduced risk of depression scores in multiple models adjusted for potential confounders (107202). Another observational study in older adults suggests that habitual black tea consumption is associated with 50% lower odds of having depressive symptoms when compared with those who never consume tea. This association follows a dose-response pattern, with the greatest reduction in depressive symptoms found in those who drink black tea more frequently, in larger amounts, and for longer durations of many years. While the study suggests that social engagement such as drinking tea in a teahouse or restaurant with other people may mediate the association between other types of tea such as oolong or green tea and depressive symptoms, mild black tea consumption for a duration of 6-9 years and for ≥160 cup-years is associated with lower odds of having depressive symptoms independently of social engagement (112235). Since this study was conducted in Chinese adults, it is unclear if the findings are generalizable to other populations.
• Diarrhea. Black tea seems to improve stool consistency in children with acute nonbacterial diarrhea. Details: Preliminary clinical research in children with acute nonbacterial diarrhea shows that taking a one-time dose of black tea 500-1000 mg as tablets dissolved in water improves stool consistency after 24 hours when compared with placebo (97126).
• Halitosis. It is unclear if black tea is beneficial in patients with halitosis. Details: A very small study in healthy adults shows that rinsing with 10 mL of black tea for 30 seconds following L-cysteine-induced halitosis improves the concentration of volatile sulfur compounds in breath samples when compared with baseline. These concentrations also were improved at 2 hours, but not at 1 hour, when compared with control. It is unclear if the improvement from baseline differed between groups (107203).
• Headache. Although there has been interest in consuming black tea for headache, there is insufficient reliable information about the clinical effects of black tea for this purpose.
• Hyperlipidemia. The evidence for the benefits of black tea in reducing cholesterol is conflicting. Details: One small clinical study in mildly hypercholesterolemic adults shows that drinking black tea reduces total cholesterol and low-density lipoprotein (LDL) cholesterol levels (36401). However, other studies have found that drinking black tea or taking black tea extract does not reduce cholesterol or triglyceride levels in healthy people or in those with cardiovascular risk factors (36376,36436,36581,36592). Meta-analyses of clinical research also report conflicting findings. Several meta-analyses in healthy people and in patients with coronary artery disease or hypercholesterolemia suggest that drinking black tea or taking black tea extract does not reduce total cholesterol or LDL cholesterol levels when compared with placebo (92407,102738). However, several other small meta-analyses of clinical studies in healthy people or those at risk for cardiovascular disease show that drinking black tea 3-5 servings daily or taking black tea extract 1-6 grams daily for up to 6 months modestly reduces LDL cholesterol levels when compared with placebo (90146,92408). Reasons for the conflicting findings are not entirely clear. One analysis suggests that black tea has a greater effect on LDL cholesterol in patients with higher cardiovascular risks than those who are healthy (92408). The effect of black tea on cholesterol levels does not appear to be influenced by the duration of treatment or the type of black tea used (tea leaf vs. tea extract) (92407,92408).
• Hypertension. Consumption of black tea seems to modestly reduce blood pressure, although any effect may not be considered clinically significant. Details: Most epidemiological research and some meta-analyses of clinical research show that consumption of 3-5 cups of black tea daily or black tea extracts 6 grams daily for up to 6 months can modestly reduce blood pressure, although any benefits are not likely to be considered clinically significant (36400,90146,92405,104582,104583). One meta-analysis of clinical research in a mixed population with normotension, hypertension, coronary artery disease, mild hypercholesterolemia, or at high risk of cardiovascular disease shows that taking black tea 300-1800 mL daily for 7 days to 6 months reduces systolic blood pressure by about 1.5 mmHg and diastolic blood pressure by about 0.8 mmHg when compared with control (104582). Other analyses show similar reductions of up to 2 mmHg (90146,92405). However, the effect in patients with hypertension is unclear because this population is rarely analyzed separately. In a meta-analysis of three clinical trials limited to patients with hypertension, and excluding studies related to purified black tea extracts or isolated components, there was no statistically significant effect on blood pressure when compared with control (104583). Interestingly, most of the individual clinical studies in these analyses did NOT find a reduction in blood pressure from black tea consumption (104582). This might be because most of these studies had a short duration (1452,36376,36581,104583) or were underpowered to detect a modest effect (36436). Furthermore, these studies did not use out-of-office blood pressure monitoring, such as 24-hour ambulatory blood pressure monitoring (ABPM). A robust clinical study using ABPM in patients with normotension and hypertension shows that drinking 3 cups of black tea (1493 mg powdered black tea solids containing 429 mg of polyphenols) daily for 6 months results in about 2 mmHg reduction in both systolic and diastolic blood pressure when compared with placebo (97127).
• Kidney stones (nephrolithiasis). It is unclear if consumption of black tea is beneficial for the prevention of kidney stones. Details: Population research suggests that consuming one 8 oz cup of tea, such as black tea, daily is associated with an 8% decreased risk of developing kidney stones in females (4216). However, a very small clinical study in healthy adults without a history of kidney stones shows that drinking 1.5 liters of black tea standardized to contain oxalate 86 mg daily for 5 days does not increase urinary risk factors for kidney stone formation when compared with control (112248). The validity of these effects is limited by the very small sample size. Additionally, it is unclear if these findings may be due to the caffeine content in black tea, as opposed to black tea itself.
• Oral cancer. Although there has been interest in consuming black tea for oral cancer, there is insufficient reliable information about the clinical effects of black tea for this purpose.
• Overall mortality. Consuming black tea may be associated with a modest reduction in overall mortality. Details: A prospective cohort study of nearly 500,000 adults between 40-69 years of age in the United Kingdom Biobank shows that consuming black tea in quantities greater than 1 cup daily is associated with a modestly reduced all-cause mortality over a mean follow-up of about 11 years. Increasing consumption beyond 2-3 cups per day does not further reduce overall mortality rate (108970).
• Pancreatic cancer. It is unclear if consumption of black tea is associated with a reduced risk of pancreatic cancer. Details: One prospective, observational study has found that Japanese males who drink more than 1 cup of black tea daily are not at a lower risk of developing pancreatic cancer when compared with those who almost never drink black tea (36482). However, another observational study in Polish males has found that increased tea consumption over a lifetime is associated with a reduced risk of pancreatic cancer (36550).
• Pregnancy-induced hypertension. It is unclear if maternal consumption of black tea reduces the risk of pregnancy-induced hypertension. Details: A retrospective cohort study in pregnant adults without chronic hypertension suggests that tea consumption at any point during pregnancy is associated with 44% increased odds of pregnancy-induced hypertension, 86% increased odds of gestational hypertension, and 193% increased odds of early-onset preeclampsia (EOPE). Subgroup analysis suggests that timing affects this association, with those who drink tea in the first trimester more likely to develop gestational hypertension, while those who drink tea in the second semester are more likely to develop pregnancy-induced hypertension. Exposure time may also influence the association, with those who begin drinking tea prior to pregnancy lacking a significant risk of developing pregnancy-induced hypertension, while those who begin drinking tea during pregnancy are at an increased risk. In those who drink tea during pregnancy, maternal characteristics may also mediate the risk of pregnancy-induced hypertension. There is a greater risk observed in pregnant adults with overweight or obesity before pregnancy or those having multiple births. The odds of developing pregnancy-induced hypertension with black tea are much higher than with green tea or herbal tea (112246). The validity of these findings is limited by the use of a retrospective chart review. Since this study was conducted in Chinese adults, it is unclear if the findings are generalizable to other populations.
• Prostate cancer. It is unclear if consumption of black tea is beneficial for reducing the risk of prostate cancer. Details: Observational research has found that black tea consumption is associated with a reduced risk of prostate cancer when compared with those who almost never drink black tea (36482).
• Renal cell carcinoma. It is unclear if consumption of black tea is beneficial for reducing the risk of kidney cancer. Details: Prospective, observational research in males has found that drinking higher amounts of tea, including black and green tea, is associated with an increased risk of kidney cancer when compared with nonregular tea consumption (36474).
• Stress. It is unclear if consumption of black tea is beneficial for reducing stress. Details: Preliminary clinical research in healthy, nonsmoking males shows that drinking black tea daily for 6 weeks does not improve blood pressure, heart rate, or subjective stress ratings in response to stressful tasks when compared with placebo (36426).
• Stroke. It is unclear if consumption of black tea is associated with a reduced risk of stroke or death from stroke. Details: Several prospective, observational studies have found that higher intake of tea, including black tea, is associated with a decreased incidence of stroke when compared with lower intake (7716,107204), as well as a modestly reduced risk of stroke-related mortality (108970). Consumption of at least 2 cups daily of tea, including black tea, is associated with a 16% reduced risk of stroke when compared with drinking no tea. Drinking 2-3 cups daily of both tea and coffee is associated with a 38% reduced risk of stroke when compared with not drinking either of these beverages. The combination of 0.5-1 cups of coffee and 2-3 cups of tea daily, but not tea alone, also is associated with a 50% reduced risk of post-stroke dementia when compared with not drinking tea and coffee (107204). More evidence is needed to rate black tea for these uses.

(Read more about BLACK TEA)

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Diabetes. Small clinical studies suggest that oral cardamom may slightly reduce glycated hemoglobin (HbA1c) in patients with type 2 diabetes, but it does not appear to improve blood glucose, blood pressure, or cholesterol levels in these patients. Details: A small clinical study in overweight or obese adults with type 2 diabetes who are taking antidiabetes medication shows that taking cardamom 1 gram three times daily for 10 weeks reduces HbA1c by 0.4% and improves insulin and triglyceride levels when compared with a rusk powder placebo (101887). However, other small clinical studies show that taking cardamom 1 gram three times daily does not reduce fasting blood glucose, blood pressure, or total cholesterol levels, or improve anthropometric measures in patients with type 2 diabetes (95597,99436,101887).
• Dyspepsia. Although there has been interest in using oral cardamom for dyspepsia, there is insufficient reliable information about the clinical effects of cardamom for this purpose.
• Epilepsy. Although there has been interest in using oral cardamom essential oil for epilepsy, there is insufficient reliable information about the clinical effects of cardamom for this purpose.
• Hyperlipidemia. Small clinical studies suggest that oral cardamom may modestly reduce triglyceride levels in patients with hyperlipidemia, but it does not seem to improve other lipid levels in these patients. Details: A meta-analysis of mostly small randomized controlled trials shows that taking cardamom 3 grams daily for 8-12 weeks does not improve total, low-density lipoprotein (LDL), or high-density lipoprotein (HDL) cholesterol levels. However, it might modestly reduce triglyceride levels when compared with placebo (101886).
• Hypertension. It is unclear if oral cardamom powder is beneficial in patients with hypertension. Details: A small clinical study in adults with newly-diagnosed, untreated, stage 1 essential hypertension shows that taking cardamom powder 1.5 grams orally twice daily for 12 weeks reduces systolic blood pressure by about 19 mmHg and diastolic blood pressure by about 12 mmHg when compared to baseline (95308). The validity of these findings is limited by the lack of a comparator group.
• Irritable bowel syndrome (IBS). Although there has been interest in using oral cardamom for IBS, there is insufficient reliable information about the clinical effects of cardamom for this purpose.
• Nausea and vomiting. Although there has been interest in using oral cardamom for nausea and vomiting, there is insufficient reliable information about the clinical effects of cardamom for this purpose.
• Nonalcoholic fatty liver disease (NAFLD). It is unclear if oral cardamom is beneficial in patients with NAFLD. Details: A small clinical study in overweight or obese patients with NAFLD shows that taking cardamom 1000 mg three times daily for 3 months improves some measures of cardiovascular and hepatic health when compared with placebo. Fatty liver grade, as measured by sonography, improved in 42% of patients taking cardamom, compared with 4.5% of those taking placebo. High-density lipoprotein (HDL) cholesterol levels, triglyceride levels, and insulin resistance also improved by a moderate amount. However, taking cardamom did not affect fasting blood glucose, body mass index (BMI), or low-density lipoprotein (LDL) cholesterol levels (101885).
• Obesity. It is unclear if oral cardamom is beneficial in patients with diabetes. Details: A small clinical study in overweight adults with diabetes shows that drinking black tea steeped with 3 grams of cardamom powder in three divided doses daily for 8 weeks does not affect weight, waist circumference, or blood pressure when compared with baseline or black tea only (95597).
• Polycystic ovary syndrome (PCOS). It is unclear if oral cardamom powder is beneficial in patients with PCOS. Details:A small clinical study in patients with PCOS shows that taking cardamom powder 1 gram three times daily for 16 weeks while following a low-calorie diet improves cyst size and number, reduces levels of testosterone and luteinizing hormone, increases levels of follicle stimulating hormone, and reduces levels of several inflammatory markers when compared with placebo plus a low-calorie diet (107920).
• Postoperative nausea and vomiting (PONV). Aromatherapy with cardamom essential oil has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: One small clinical study shows that applying a mixture of essential oils from ginger, cardamom, and tarragon topically to the neck at the first sign of PONV can inhibit nausea and/or vomiting for 30 minutes in 50% to 88% of postoperative patients. The treatment effect appears to vary depending on the number of emetic drugs given during anesthesia or postoperatively, and whether the drugs were given during or after the operation (77054). Another small study shows that aromatherapy with a mixture of ginger, spearmint, peppermint, and cardamom, as 3 inhalations from a gauze pad, reduces nausea scores by 43% when compared with placebo. When compared with ginger aromatherapy alone, nausea scores were reduced by 15%. Using the combination aromatherapy also reduced the need for anti-nausea medications by 40% when compared with placebo and by 15% when compared with ginger aromatherapy (95307). It is unclear if these benefits are due to cardamom, other ingredients, or the combination.
• Pregnancy-induced nausea and vomiting. Although there has been interest in using oral cardamom for pregnancy-induced nausea and vomiting, there is insufficient reliable information about the clinical effects of cardamom for this purpose.
• Respiratory tract infections. Although there has been interest in using oral cardamom for various respiratory tract infections, including bronchitis, influenza, and the common cold, there is insufficient reliable information about the clinical effects of cardamom for these conditions. More evidence is needed to rate cardamom for these uses.

(Read more about CARDAMOM)

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Cardiovascular disease (CVD). Although there is interest in using oral chaga for CVD, there is insufficient reliable information about the clinical effects of chaga for this condition.
• Coronavirus disease 2019 (COVID-19). Although there has been interest in using oral chaga for COVID-19, there is insufficient reliable information about the clinical effects of chaga for this purpose.
• Diabetes. Although there is interest in using oral chaga for diabetes, there is insufficient reliable information about the clinical effects of chaga for this condition. More evidence is needed to rate chaga for these uses.

(Read more about CHAGA)

POSSIBLY EFFECTIVE

• Ventilator-associated pneumonia (VAP). Clove mouthwash might reduce the risk of acquiring pneumonia in patients on mechanical ventilation. Details: A large clinical trial in adults in the intensive care unit on mechanical ventilation shows that administration of a clove extract 6.66% mouthwash, 15 mL twice daily for 5 days, results in a 2-fold lower incidence of ventilator-associated pneumonia when compared with chlorhexidine mouthwash (112151).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Alveolar osteitis. Although there has been interest in using topical clove for alveolar osteitis, there is insufficient reliable information about the clinical effects of clove for this purpose.
• Anal fissures. It is unclear if topical clove oil is beneficial in patients with anal fissures. Details: Preliminary clinical research in patients with chronic anal fissures shows that applying clove oil 1% cream for 6 weeks heals fissures in 60% of patients by the 3-month follow-up, compared with only 12% of patients who used topical lidocaine 5% cream and stool softeners (43487).
• Cough. Although there has been interest in using oral clove for cough, there is insufficient reliable information about the clinical effects of clove for this purpose.
• Dental plaque. Topical clove has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that using a specific toothpaste (Sudantha, Link Natural Products Ltd.) containing a combination of clove, Acacia chundra Willd., malabar nut, bullet wood tree, black pepper, Indian beech, gall oak, Terminalia, and ginger twice daily for 12 weeks can reduce dental plaque, bleeding, and bacteria counts in the mouth when compared with placebo (43570). Other clinical research shows that administration of a mouth rinse containing clove, tea tree oil, and basil 10 mL twice daily for 21 days is as effective as a commercially available mouth rinse containing thymol, eucalyptol, menthol, and methyl salicylate in reducing dental plaque and gum inflammation (92160). It is unclear whether clove, another ingredient, or a combination of these ingredients is responsible for these effects.
• Diarrhea. Although there has been interest in using oral clove for diarrhea, there is insufficient reliable information about the clinical effects of clove for this purpose.
• Dyspepsia. Although there has been interest in using oral clove for dyspepsia, there is insufficient reliable information about the clinical effects of clove for this purpose.
• Flatulence. Although there has been interest in using oral clove for flatulence, there is insufficient reliable information about the clinical effects of clove for this purpose.
• Gingivitis. Although there has been interest in using topical clove for gingivitis, there is insufficient reliable information about the clinical effects of clove for this purpose.
• Halitosis. Although there has been interest in using oral clove for halitosis, there is insufficient reliable information about the clinical effects of clove for this purpose.
• Hangover. It is unclear if oral clove flower extract is beneficial for reducing hangover severity. Details: Preliminary clinical research in a very small number of healthy males with a history of hangovers shows that taking a clove flower bud polyphenol extract 250 mg prior to drinking brandy (42.8% alcohol) decreases hangover severity scores by around 55% when compared with placebo (100597).
• Hyperhidrosis. It is unclear if topical clove oil is beneficial in patients with hyperhidrosis. Details: Preliminary clinical research in patients with hyperhidrosis of the palms shows that topical application of clove oil 45% in liposome base twice daily for 2 weeks improves hyperhidrosis severity and decreases the rate of sweating by around 34% when compared with a saline control (100596). The validity of these findings is limited by a lack of subject randomization.
• Impaired glucose tolerance (prediabetes). It is unclear if oral clove flower extract is beneficial in patients with prediabetes. Details: Preliminary clinical research in a very small number of patients with prediabetes shows that taking a polyphenolic extract from clove flower buds 250 mg daily for 30 days decreases pre-prandial plasma glucose by 14 mg/dL and postprandial plasma glucose by 40 mg/dL when compared to baseline (100595). The validity of these findings is limited by the very small size of the study and the lack of a control group.
• Mosquito repellent. Small clinical studies suggest that topical clove oil may repel mosquitos for up to 4-5 hours. Details: Preliminary clinical research shows that topical application of undiluted clove oil can repel 100% of mosquitoes for up to 4 hours (43427). Other preliminary research shows that topical application of gel containing clove oil 20% can repel 86% to 97% of mosquitoes for 5 hours (43411).
• Nausea and vomiting. Although there has been interest in using oral clove for nausea and vomiting, there is insufficient reliable information about the clinical effects of clove for this purpose.
• Oral mucositis. Although there has been interest in using topical clove for oral mucositis, there is insufficient reliable information about the clinical effects of clove for this purpose.
• Pain (acute). It is unclear if topical clove is beneficial in patients with acute pain. Details: Preliminary clinical research shows that topical application of a gel containing ground cloves, applied as 4 grams of gel for 5 minutes prior to dental anesthesia injection, can reduce needle stick pain when compared with placebo. The effect of the clove gel on pain seems to be comparable to benzocaine 20% gel (43448).
• Premature ejaculation. Topical clove has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that administration of a multi-ingredient cream preparation (SS Cream) containing clove flower, Panax ginseng root, Angelica root, Cistanches deserticola, Zanthoxyl species, Torlidis seed, Asiasari root, cinnamon bark, and toad venom to the glans penis, one hour prior to intercourse and washed off immediately before intercourse, increases ejaculatory latency time by over 4-fold when compared with placebo in adults with premature ejaculation (2537). It is unclear whether clove, another ingredient, or a combination of these ingredients is responsible for these effects.
• Pruritus. There is limited evidence on the topical use of clove oil in patients with chronic pruritus. Details: Preliminary clinical research in patients with chronic pruritus shows that applying clove oil 10% in petroleum jelly to the skin twice daily for 2 weeks reduces the daily duration of itching by 48 minutes and improves symptom severity and disability scores when compared with placebo (96950). More evidence is needed to rate clove for these uses.

(Read more about CLOVE)

POSSIBLY EFFECTIVE

• Cardiovascular disease (CVD). Dietary cocoa seems to be beneficial for CVD prevention. Oral cocoa extract may reduce the risk of CVD-related death, but it is unclear if it can prevent other CVD-related outcomes like myocardial infarction (MI) or stroke. Details: A large clinical trial in adults without CVD shows that taking a specific cocoa extract daily for around 3.5 years reduces the risk of CVD-related death by 27%, but does not reduce the risk of cardiovascular events, including MI or stroke, or overall mortality when compared with placebo. This specific cocoa extract contained 500 mg of flavanols, including 80 mg of epicatechins (108898). In 2023, the US Food and Drug Administration (FDA) approved a qualified health claim stating that very limited scientific evidence suggests that the cocoa flavanols in high flavanol cocoa powder, for products containing at least 4% naturally conserved cocoa flavanols, may reduce the risk of cardiovascular disease (110017). Observational research in adults without CVD has also found that consuming a higher amount of cocoa is associated with a 10% lower risk of CVD and an up to 50% lower risk of CVD-related mortality when compared with consuming lower amounts of cocoa. Consuming more than 90 grams of cocoa per week did not add further benefit (14288,97192). Additional clinical research shows that taking cocoa flavanols 450 mg twice daily for one month improves cholesterol levels and blood pressure values, resulting in improved Framingham Risk Scores in healthy patients. These scores correspond to a 21% decrease in the 10-year risk for coronary heart disease, a 22% decrease in the risk for CVD, a 31% decrease in the risk for MI, and a 30% decrease in the risk for CVD-related mortality (92273). There is also evidence that consuming cocoa might improve flow-mediated dilatation, a measure of endothelial dysfunction. Meta-analyses of clinical research have found that increased cocoa or chocolate intake significantly improves flow-mediated dilatation. This is seen with intakes of 19-54 grams of cocoa daily, 46-100 grams of dark chocolate daily, or cocoa products containing 16.6-1080 mg of flavonoids daily (17187,42059,42137).
• Hypertension. Oral cocoa seems to be beneficial for modestly decreasing blood pressure in hypertensive patients. It is unclear if dietary cocoa is beneficial for preventing hypertension. Details: Overall, clinical research shows that chocolate or cocoa containing 25-1080 mg daily of flavonoids modestly reduces blood pressure in hypertensive patients (14306,15655,15752,42092,42107,42169,97190,103247). Meta-analyses of clinical research show that consuming commercially available dark chocolate or flavanol-enriched chocolate/cocoa products daily for 2-8 weeks reduces systolic blood pressure (SBP) by around 4 mmHg and diastolic blood pressure (DBP) by around 2 mmHg in patients with hypertension when compared to control products with low levels of flavanols or no flavanols (42169,97190). Additionally, a meta-analysis of clinical trials in middle-aged and elderly patients with or without hypertension shows that consuming cocoa products daily for 4-18 weeks reduces SBP and DBP by around 3 mmHg and 1.5 mmHg, respectively, when compared with control products (103249). Blood pressure lowering seems to occur more readily in hypertensive or pre-hypertensive individuals when compared with normotensive individuals (14306,15655,15752,42092,42107,42169,97190,103247). Consumption of cocoa might also reduce the risk of developing hypertension in normotensive patients. Observational research has found that long-term consumption of moderate amounts of cocoa (2.2 grams to 6.1 grams daily) is associated with a 7% lower risk of hypertension when compared with consumption of less than 0.61 grams daily. However, consumption of amounts greater than 6.1 grams daily does not seem to reduce hypertension risk. Also, this benefit seems to be limited to patients consuming cocoa from plain chocolate, as consumption of cocoa from desserts was linked with a 9% greater risk of hypertension (103248).

POSSIBLY INEFFECTIVE

• Hypercholesterolemia. Oral cocoa does not seem to be beneficial for reducing cholesterol levels in patients with hypercholesterolemia. Details: Some preliminary clinical research in healthy, normocholesterolemic males shows that diets high in stearic acid from cocoa butter result in lower cholesterol levels when compared with diets high in myristic acid from dairy butter. However, a diet high in stearic acid from cocoa butter does not significantly lower cholesterol when compared to baseline in this population (15063). A meta-analysis of 10 clinical studies shows that cocoa or dark chocolate can reduce total cholesterol and low-density lipoprotein (LDL) cholesterol in normocholesterolemic patients (42125). However, some preliminary clinical research in patients with hypercholesterolemia shows that drinking a high-flavanol cocoa beverage daily for 6 weeks does not reduce cholesterol when compared with a low-flavanol cocoa beverage (42013). Also, while some clinical research shows that taking cocoa powder 26 grams with sugar daily for 12 weeks can increase high-density lipoprotein (HDL) cholesterol levels when compared with sugar alone in normocholesterolemic and hypercholesterolemic patients (42026), taking cocoa or dark chocolate 13-41 grams daily does not seem to lower total cholesterol or LDL cholesterol in these patients (42026,42029,42225).
• Stretch marks (striae gravidarum). Topical cocoa butter does not seem to be beneficial for preventing stretch marks during pregnancy. Details: Clinical research shows that topical application with a cream containing cocoa butter 25% to the abdomen daily, starting during the second and third trimesters and continuing until delivery, does not prevent stretch marks when compared with a placebo cream (105261). Other clinical research shows that topical application with a cream containing cocoa butter and vitamin E as tocopheryl acetate to the abdomen, breasts, and thighs, daily, starting during the second trimester and continuing until delivery, does not reduce the prevalence or severity of stretch marks when compared to a cream not containing these ingredients (105262). More research is needed in individuals of all skin types.

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Age-related cognitive decline. It is unclear if oral cocoa is beneficial for improving cognitive function in healthy older adults. Details: Some small clinical studies in healthy adults over the age of 60 with or without existing cognitive impairment show that sub-chronic intake of cocoa at doses of 45 mg, 520 mg, or 990 mg once daily for 8 weeks, or as a cocoa drink containing flavanols 609 mg daily for 30 days, modestly improves some measures of cognitive function, including task switching, visual attention, and verbal fluency (42184,92269). However, it does not improve performance on the mini mental state exam (92269). Also, one clinical study in healthy adults aged 60 years and older shows that consuming a dark chocolate bar containing 11 grams of cocoa and drinking 237 mL of an artificially sweetened drink containing 11 grams of cocoa daily for 6 weeks does not improve neuropsychological function when compared with placebo (42050). Additional preliminary clinical research in postmenopausal females aged 50-64 years shows that adding chocolate 10 grams daily, containing 99% cocoa, for 6 months does not improve most measures of cognitive function when compared with not taking cocoa (105259). Reasons for the discrepancies are unclear but may relate to the dose of cocoa, the duration of intake, or the specific cognitive testing procedures conducted.
• Age-related testosterone deficiency. Oral cocoa has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in healthy middle-aged adults shows that taking a combination product containing cocoa seed extract and pomegranate rind (Tesnor, Gencor) daily for 56 days increases serum testosterone levels and hand-grip strength and improves measures of sexual function and psychological well-being when compared with placebo (111527). It is unclear if these effects are due to cocoa, pomegranate, or the combination.
• Aging skin. It is unclear if oral cocoa is beneficial for aging skin. Details: Preliminary clinical research in adults with aging skin shows taking a specific product (GliSODin Skin Nutrients Advanced Anti-Aging Formula, Isocell North America Inc.) 780 mg three times daily, containing cocoa extract, as well as superoxide dismutase, krill oil, sea buckthorn, hyaluronic acid, and other nutrients, in combination with daily use of tazarotene cream 0.1%, for 90 days improves fine wrinkling, photodamage, and skin elasticity when compared with tazarotene cream and placebo (91778). Additional preliminary clinical research in patients with photoaged skin shows that drinking a cocoa drink containing 320 mg of flavanols daily for 24 weeks improves wrinkle depth and skin elasticity, but not skin hydration, when compared with placebo (92274).
• Asthma. Although there has been interest in using oral cocoa for asthma, there is insufficient reliable information about the clinical effects of cocoa for this condition.
• Athletic performance. Although there has been interest in using oral cocoa for improving athletic performance, there is insufficient reliable information about the clinical effects of cocoa for this use.
• Atrial fibrillation. It is unclear if dietary cocoa is beneficial for preventing atrial fibrillation. Details: Most population research has found that chocolate consumption is not associated with a reduced risk of atrial fibrillation (97188,97189).
• Chronic fatigue syndrome (CFS). It is unclear if oral cocoa is beneficial for CFS. Details: In patients with CFS, preliminary clinical research shows that consuming 45 grams of a polyphenol-rich chocolate in three divided doses daily for 8 weeks can reduce fatigue by 35%, anxiety by 37%, and depression by 45%, and can increase overall function by 30%, when compared with pretreatment (42116).
• Cirrhosis. It is unclear if oral cocoa is beneficial for cirrhosis. Details: Clinical research shows that consuming a liquid test meal (Ensure Plus) in addition to dark chocolate (Lindt Excellence 85% Cocoa, Lindt & Sprüngli) 0.55 grams/kg can reduce the postprandial increase in hepatic venous pressure gradient in patients with cirrhosis when compared with the test drink alone (42164).
• Cognitive function. Research on the use of oral cocoa for improving cognitive function in healthy adults is conflicting. Details: A large clinical trial in older adults shows that taking cocoa extract containing 500 mg of flavanols daily for 3 years does not improve measures of cognitive function including global cognition, episodic memory, and executive function when compared with placebo, even when taken with a multivitamin-mineral product (Centrum Silver) (111524). Also, in middle-aged participants, clinical research shows that taking 20 grams of a dark chocolate drink mix containing 250 mg or 500 mg of polyphenols as a single dose does not seem to improve measures of cognitive function (92272). In contrast, clinical research in healthy younger individuals shows that consuming a single dose of cocoa flavanols 520-994 mg as a specific powder (Cocoapro) improves some, but not all, measures of cognitive function when examined in a situation of sustained mental effort (42093). Additionally, consuming a single dose of cocoa flavanols 900 mg as a specific powder (Acticoa) seems to improve reaction time during cognitive testing when compared with placebo in healthy adults and patients with type 1 diabetes (103251). However, acute dosing with cocoa flavanols 374-747 mg as specific powders (Acticoa) or cocoa extract capsules (Naturex) does not seem to improve measures of cognitive function, visual working memory, or ability to focus during testing in young people (99984,99985,109448). Reasons for the discrepancies are unclear but may relate to the dose of cocoa, the duration of intake, the level of stress during cognitive testing, or the specific cognitive testing procedures conducted.
• Cognitive impairment. Oral cocoa flavanols have only been evaluated in combination with other ingredients; their effect when used alone is unclear. Details: A large clinical study in adults at least 55 years of age with subjective or mild cognitive impairment shows that consuming dark chocolate containing 500 mg cocoa flavanols and taking fish oil containing DHA 1.1 grams and EPA 0.4 grams daily for 12 months does not improve cognitive function scores when compared with placebo (111453).
• Constipation. Oral cocoa husk has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research in children with chronic constipation shows that taking 2-4 sachets containing cocoa husk 8-16 grams and beta-fructosans 2-4 grams daily for 4 weeks can reduce hard stools by 45% and reduce transit time by 36 hours when compared with a placebo (42016).
• Diabetes. Several small clinical studies suggest that oral cocoa may cause small but clinically insignificant improvements in glycemic control in patients with diabetes. However, cocoa does not appear to be beneficial for the prevention of diabetes. Details: While some individual studies show conflicting results (97252,99982), two similar meta-analyses of 8-9 small clinical trials in patients with diabetes show that taking cocoa 1-54 grams daily for up to 52 weeks reduces fasting blood glucose by around 7-9 mg/dL and low-density lipoprotein (LDL) cholesterol by around 10-15 mg/dL, but does not improve glycated hemoglobin (HbA1c), insulin levels, blood pressure, total cholesterol, or high-density lipoprotein (HDL) cholesterol, when compared with control (109447,109449). This slight improvement in fasting blood glucose, along with a lack of effect on HbA1c, suggests that cocoa is unlikely to lead to clinically meaningful improvements in glycemic control. Population research has found that eating up to 60 grams of chocolate per week is associated with a lower risk of developing diabetes. Higher consumption was not found to affect diabetes risk (97192). However, secondary analysis of a large clinical study in adults aged 74 on average shows that taking an extract containing cocoa flavanols 500 mg daily, with or without a multivitamin, for about 3.5 years does not reduce the risk of developing self-reported type 2 diabetes when compared with placebo. Subgroup analysis based on body mass index, level of physical activity, or multivitamin consumption did not change results (111619).
• Exercise-induced muscle damage. It is unclear if oral cocoa flavanols are beneficial for preventing exercise-induced muscle damage. Details: Preliminary clinical research shows that taking a single dose of cocoa flavanols (Chococru Extraordinary Flavanol Cocoa) 830 mg or 1245 mg within 5 minutes of a strenuous exercise protocol does not reduce exercise-induced muscle damage over 72 hours when compared with a control providing no cocoa flavanols (105260).
• Fatigue. It is unclear if oral cocoa is beneficial for fatigue. Details: A moderate-size clinical study in otherwise healthy females aged 40-60 years with fatigue shows that consuming a beverage containing cocoa flavanols 240 mg daily for 8 weeks does not improve self-reported fatigue scores when compared with placebo (111620).
• Heart failure. It is unclear if dietary cocoa is beneficial for heart failure prevention. Details: Population research has found that consuming up to 250 grams of chocolate weekly is associated with reduced risk of heart failure. However, consuming 300 grams weekly or more does not appear to affect the risk of heart failure (97187,97191).
• HIV/AIDS-related dyslipidemia. It is unclear if oral cocoa is beneficial for HIV/AIDS-related dyslipidemia. Details: Preliminary clinical research in patients with HIV shows that consuming dark chocolate 65 grams containing cocoa 36 grams for 15 days does not affect low-density lipoprotein (LDL) cholesterol or total cholesterol levels when compared with a white chocolate placebo. However, it slightly increases levels of high-density lipoprotein (HDL) cholesterol (96472).
• Impaired glucose tolerance (prediabetes). It is unclear if oral cocoa is beneficial in patients with prediabetes. Details: A small clinical study in premenopausal adults with overweight or obesity and mild insulin resistance shows that drinking a cocoa drink high in flavanols twice daily for 4 weeks does not improve measures of insulin resistance or insulin-mediated glucose uptake when compared with a low-flavanol cocoa drink (111532).
• Influenza. Although there has been interest in using oral cocoa for influenza, there is insufficient reliable information about the clinical effects of cocoa for this condition.
• Insect repellent. It is unclear if topical cocoa oil is beneficial as an insect repellent. Details: Preliminary clinical research shows that topical application of cocoa oil, 1 mL on each leg and 0.5 mL on each forearm, reduces bites from black flies (Simulium damnosum) by 99% (41954).
• Isolated systolic hypertension. It is unclear if oral cocoa is beneficial for isolated systolic hypertension. Details: Preliminary clinical research shows that consuming 100 grams daily of cocoa polyphenol-rich dark chocolate might modestly reduce systolic and diastolic blood pressure in elderly patients with isolated systolic hypertension (13166).
• Menopausal symptoms. It is unclear if oral cocoa is beneficial for menopausal symptoms. Details: In postmenopausal individuals aged 50-64 years, preliminary clinical research shows that adding chocolate 10 grams daily, containing cocoa 99%, for 6 months reduces body fat mass by approximately 0.6 kg and body fat percentage by 0.8%, and modestly improves some measures of quality of life, when compared with no treatment (105255,105258). However, there was no effect on all measures of quality of life, general menopausal symptoms, weight, body mass index, or most measures of cognitive function (105255,105258,105259).
• Multiple sclerosis (MS). Although there has been interest in using oral cocoa for MS, there is insufficient reliable information about the clinical effects of cocoa for this condition.
• Muscle strength. Oral cocoa seed extract has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in healthy males shows that taking a combination product containing cocoa seed extract and pomegranate rind extract 400 mg daily for 8 weeks increases testosterone levels, hand grip strength, and upper arm circumference when compared with placebo (108485).
• Nipple fissures. It is unclear if topical cocoa butter is beneficial for the treatment or prevention of nipple fissures. Details: A small clinical study in breastfeeding adults shows that applying topical cocoa butter to the nipple and areola after each breastfeeding session for 10 days immediately postpartum reduces nipple pain, rashes, and cracks when compared with the topical application of the mother's breastmilk (111525). The validity of this study is limited by a lack of blinding and a high dropout rate.
• Obesity. It is unclear if oral cocoa is beneficial for obesity. Details: Preliminary clinical research in overweight or obese premenopausal females shows that following a reduced-calorie diet in addition to consuming two squares of dark chocolate and drinking 8 ounces of a sugar-free cocoa beverage daily for 18 weeks does not increase weight loss when compared with the reduced-calorie diet plus a non-chocolate snack (42130,99983).
• Parkinson disease. It is unclear if oral cocoa is beneficial for Parkinson disease. Details: Preliminary clinical research shows that consuming a single dose of dark chocolate 200 grams containing approximately 80% cocoa does not improve motor function in patients with Parkinson disease when compared with a white chocolate control, although there seems to be some improvements after one hour when compared with baseline (42156).
• Peripheral arterial disease (PAD). It is unclear if oral cocoa is beneficial for PAD. Details: A small clinical study in patients with PAD shows that drinking a flavanol-rich cocoa beverage 15 grams daily for 6 months increases 6-minute walking distance by up to 43 meters when compared with placebo (103250). Cocoa has also been studied in adults with diabetes at risk for developing PAD, with conflicting results. A small clinical study in adults with and without diabetes shows that taking a single dose of cocoa flavanols 790 mg does not improve peripheral microvascular or macrovascular parameters compared with placebo (111529). However, another small clinical study in healthy adults and those with diabetes at risk for PAD shows that taking cocoa flavanols (CocoaVia, Mars Inc) 1350 mg improves endothelial function in the brachial and femoral arteries after 2 hours when compared with placebo, suggesting that cocoa flavanols might reduce the risk of developing PAD in both populations studied (111528). The validity of this study is limited by the small sample size and short study duration.
• Stroke. It is unclear if dietary cocoa is beneficial for stroke prevention. Details: Population research has found that the highest dietary intake of chocolate is associated with a 16% reduced risk of stroke when compared with the lowest intake (97192). More evidence is needed to rate cocoa for these uses.

(Read more about COCOA)

POSSIBLY INEFFECTIVE

• Athletic performance. Taking cordyceps orally does not seem to improve athletic performance in adults. Details: One small clinical study in endurance-trained cyclists shows that taking a specific mycelial fermentation product of cordyceps (CordyMax Cs-4) 3.15 grams daily for 5 weeks does not improve endurance time trials or aerobic capacity when compared with placebo (12095). Another small study in healthy elderly adults shows that taking the same cordyceps preparation (CordyMax Cs-4) 3 grams daily for 12 weeks does not improve exercise performance when compared with placebo (46120). Research also shows that taking combination products containing cordyceps and other ingredients does not improve athletic performance when compared with control. These products have combined cordyceps (CordyMax Cs-4) 1000 mg with rhodiola 300 mg (46091) or cordyceps (CordyMax Cs-4) 2000 mg with roseroot 600 mg (Optygen, First Endurance) (15573); liquid and powdered cordyceps formulations with reishi mushroom, shiitake mushroom, bamboo, and honey (Fohow oral liquid and Fohow lingzhi capsules, FOHOW Technology Investment Group Co. Ltd.) (98686); and cordyceps (form unknown) 1.2 grams with a 930 mg mixture of extracts of ashwagandha root, green tea leaf, rhodiola root, and astragalus root (Shroom Tech Sport, Onnit Labs) (105079).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Arrhythmia. Although there is interest in using oral cordyceps for arrhythmia, there is insufficient reliable information about the clinical effects of cordyceps for this condition.
• Asthma. Oral cordyceps has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in children with asthma shows that a 619 mg capsule containing equal weights of the dried aqueous extracts of cordyceps, astragalus, skullcap, Radix stemonae, and Bulbus fritillariae daily for 6 months does not reduce the need for medication or improve symptoms when compared with placebo (32935).
• Autoimmune thyroiditis. Oral cordyceps has only been evaluated in combination with other treatmentss; its effect when used alone is unclear. Details: A meta-analysis of low-quality clinical studies in China in patients with Hashimoto's thyroiditis shows that taking cordyceps up to 9 grams daily for up to 28 weeks in addition to a low-iodine diet or levothyroxine decreases circulating thyroid antibody levels including thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb) when compared with a low-iodine diet or levothyroxine treatment alone. In the subgroup of patients with hypothyroidism, taking cordyceps with levothyroxine increases free thyroxine (FT4) but does not affect free triiodothyronine (FT3) or thyroid-stimulating hormone (TSH) levels when compared with levothyroxine alone. (113622).
• Chronic kidney disease (CKD). Small clinical studies suggest that oral cordyceps may modestly improve biomarkers in some patients with CKD. Details: A meta-analysis of clinical research in patients in China with CKD shows that taking cordyceps 0.6-2 grams orally three times daily, along with standard treatment, seems to decrease serum creatinine levels by 0.6 mg/dL and increase creatinine clearance by 9.2 mL/min when compared with standard treatment alone (92829). Another meta-analysis of clinical studies in patients in China with diabetic kidney disease shows that taking cordyceps 0.5-2 grams orally three times daily along with angiotensin-converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB) decreases blood urea nitrogen by 2 mg/dL and decreases serum creatinine levels by 0.1 mg/dL when compared with ACEI/ARB treatment alone (92830). Most individual studies in these analyses used Bailing (Cs-C-Q80) or Jinshuibao (Cs-4), fermented cordyceps mycelial products (92829,92830). Both of these analyses are limited by the low methodological quality and short duration (usually 1-6 months) of most of the included studies.
• Chronic obstructive pulmonary disease (COPD). Preliminary clinical studies suggest that oral cordyceps may modestly improve symptoms of COPD. Details: A meta-analysis of preliminary clinical research in patients with moderate or severe COPD shows that taking cordyceps alone or as part of a formulation containing other products for up to 12 months improves lung function and reduces the incidence of an acute exacerbation by a small amount. Also, the distance walked in 6 minutes is increased by about 45 meters, which was considered clinically meaningful. Most individual studies in this analysis used Bailing (Cs-C-Q80) or Jinshuibao (Cs-4), fermented cordyceps mycelial products, in combination with conventional treatments with conventional treatments alone (109705). This analysis is limited by the low methodological quality of the included studies.
• Contrast induced nephropathy. Small clinical studies suggest that oral cordyceps may modestly reduce contrast induced nephropathy. Details: A preliminary clinical study in patients with diabetic nephropathy shows that taking a specific cordyceps mycelial product (Corbrin; CS-C-Q80) 2-3 grams orally three times daily for 3 days before and after angiography reduces the risk of contrast induced nephropathy by about 48% to 66% when compared to standard treatment (92827). However, other preliminary clinical research in patients with stable angina pectoris shows that taking the same cordyceps product 3 grams orally three times daily for 3 days before and after angioplasty does not decrease the prevalence of contrast induced nephropathy when compared to standard therapy (92826). Reasons for these discrepancies are not clear but may relate to the small size and heterogenous populations in these studies.
• Diabetic nephropathy. Early research suggests that oral cordyceps may modestly improve kidney function in patients with diabetic kidney disease. Details: A meta-analysis of low to moderate quality clinical research in patients with diabetic kidney disease shows that taking cordyceps as adjunctive therapy to angiotensin-converting enzyme inhibitors or angiotensin receptor blockers for 2-24 weeks modestly improves kidney function when compared to these medications alone. Kidney function was based on markers such as blood creatinine and urea nitrogen, as well as urinary albumin and total protein. There were also modest improvements in systolic and diastolic blood pressure, triglycerides, and low-density lipoprotein (LDL) cholesterol. There was no effect on glycemic indices. The effect of cordyceps on disease progression or cardiovascular events is unclear (111903).
• Cough. Although there is interest in using oral cordyceps for cough, there is insufficient reliable information about the clinical effects of cordyceps for this purpose.
• Fatigue. Although there is interest in using oral cordyceps for fatigue, there is insufficient reliable information about the clinical effects of cordyceps for this purpose.
• Hepatitis B. Although there is interest in using oral cordyceps for hepatitis B, there is insufficient reliable information about the clinical effects of cordyceps for this condition.
• Hypercholesterolemia. Although there is interest in using oral cordyceps for hypercholesterolemia, there is insufficient reliable information about the clinical effects of cordyceps for this condition.
• Kidney failure. Small clinical studies suggest that oral cordyceps may improve inflammatory markers in patients on hemodialysis. Details: A meta-analysis of small clinical trials in patients in China on hemodialysis suggests that adding cordyceps to standard treatment does not seem to improve serum creatinine levels but may improve certain markers of inflammation, such as C-reactive protein, when compared with placebo. Most individual studies in this analysis used Bailing (Cs-C-Q80) or Jinshuibao (Cs-4), fermented cordyceps mycelial products (105076).
• Kidney transplant. Small clinical studies suggest that oral cordyceps is no better than standard treatment in patients with kidney transplant. Details: A meta-analysis of 4 heterogeneous clinical trials evaluating patients in China immediately post-kidney transplant or patients with complications post-kidney transplant suggests that adding cordyceps to standard therapy with cyclosporine and steroids is no better than adding azathioprine 50-150 mg for improving overall survival or graft survival or reducing rejection risk. However, there was a non-significant trend to reduced risk of graft rejection in the cordyceps group (95905). A higher quality systematic review, which determined the available studies were too heterogeneous to pool together in a meta-analysis, suggests that adding cordyceps 3-6 grams to standard therapy daily is no better than azathioprine or cyclosporine for improving organ rejection, kidney function, or survival in patients after kidney transplant (92828). All individual studies in these analyses used Bailing (Cs-C-Q80) fermented cordyceps mycelial product (95905,92828).
• Sexual dysfunction. It is unclear if oral cordyceps is beneficial in patients with sexual dysfunction. Details: Preliminary clinical research shows that taking a specific mycelial fermentation product of cordyceps (CordyMax Cs-4) approximately 3 grams daily for 40 days can improve symptoms of hyposexuality in 66% of patients, compared with 32% of patients taking natural cordyceps and 24% of patients taking placebo (46145).
• Tinnitus. Although there is interest in using oral cordyceps for tinnitus, there is insufficient reliable information about the clinical effects of cordyceps for this condition. More evidence is needed to rate cordyceps for these uses.

(Read more about CORDYCEPS)

POSSIBLY EFFECTIVE

• Dysmenorrhea. In people with dysmenorrhea, taking oral ginger seems to reduce pain. Clinical research shows that ginger might be comparable to ibuprofen or mefenamic acid. In addition, taking ginger seems to be beneficial when used as an adjunct to mefenamic acid 250 mg twice daily. Details: Clinical research in individuals at least 15 years of age shows that ginger can reduce pain from dysmenorrhea. Clinical studies show that taking ginger powder 500-2000 mg daily usually for the first 3-4 days of a menstrual cycle modestly decreases pain severity by an average of 2.3-2.7 points on a 10-point scale when compared to control groups (89889,89899,91139,91892,96255,106077). However, a meta-analysis of clinical research shows that taking ginger does not reduce pain duration when compared with placebo (106077). Clinical research also shows that ginger might be as effective as some anti-inflammatory agents. Taking a specific ginger extract (Zintoma, Goldaru) 250 mg four times daily for 3 days at the beginning of the menstrual period or until pain relief improves symptoms similarly to ibuprofen or mefenamic acid (17931,96259,106077). Also, taking a ginger extract 200 mg four times daily for 3-4 days at the beginning of pain is equally effective to taking Novafen, a combination of acetaminophen, caffeine, and ibuprofen (99444). Ginger also seems to improve pain when given as an adjunct to anti-inflammatory agents. A small clinical study in young females with dysmenorrhea shows that adding ginger (Vomigone, Dineh Co.) 500 mg daily to mefenamic acid 250 mg twice daily for 5 days further reduces pain when compared with taking mefenamic acid alone (102464).
• Osteoarthritis. Most clinical research shows that taking ginger extract by mouth improves pain in some patients with osteoarthritis. Topical ginger, on the other hand, has not shown benefit for knee osteoarthritis in low quality research. Details: Meta-analyses of clinical research show that taking ginger extract 500-1000 mg daily for 3-12 weeks can modestly improve pain when compared with placebo in some patients with osteoarthritis of the knee or hip (96253,103357). However, a meta-analysis of two clinical studies shows that taking ginger extract about 500 mg daily for 6 weeks does not have an effect on function (103357). Some clinical research has also compared ginger to conventional drug treatment. In one clinical trial, there was no significant difference between ginger extract 30 mg daily and ibuprofen 400 mg three times daily for one month in patients with osteoarthritis of the hip or knee (17930). However, taking a specific ginger extract (Eurovita Extract 33; EV ext-33) orally 170 mg three times daily for 3 weeks was significantly less effective than ibuprofen 400 mg three times daily for reducing pain (7048). Since ginger is thought to take several weeks for significant benefit, this trial might not have lasted long enough. Ginger has also been compared with diclofenac. When used orally as 1500 mg daily in two divided doses, ginger is less effective than oral diclofenac 100 mg daily in two divided doses, or the combination of ginger and diclofenac, for 12 weeks (89898). Various studies have evaluated formulations containing ginger with other ingredients. These combinations have all been shown to improve osteoarthritis pain, and in some cases, functionality. Studied formulations include ginger (Eurovita Extract 35; EV ext-35) 340 mg with glucosamine (Zinaxin glucosamine, Ferrosan AS) 1000 mg daily for 4 weeks, a ginger extract with an alpinia (Alpinia galanga) extract (Eurovita Extract 77; EV ext-77) 255 mg twice daily for 6 weeks, a ginger extract with curcuminoids, and extracts of devil's claw, Boswellia serrata, and celery (Tregocel) for 36 weeks, or Ayurvedic shunthi-guduchi formulations containing ginger, Indian gooseberry, and Tinospora cordifolia, either with or without Boswellia serrata (7084,18210,89557,106078). However, it's too early to know if the effects of these combination agents are associated with ginger or other ingredients in the formulations. Topical ginger, alone or in combination with other ingredients, has also been studied for knee osteoarthritis. Although a meta-analysis of two randomized clinical trials shows no evidence of benefit of topical ginger for pain and disability when compared with placebo or standard therapy (103357), some benefits have been shown in individual preliminary studies (20340,20341,89897,96668,97537,97542). These trials have used a specific gel containing ginger and plai 4% by weight (Plygersic gel, Thailand Institute of Scientific and Technological Research) 4 grams/day in four divided doses for 6 weeks (89897), an ointment composed of ginger, cinnamon, mastic (Saghez), and sesame oil twice daily for 6 weeks (20340), or one gram of ginger extract 5% (standardized to 11.18% of 6-gingerol) in a nanostructure lipid carrier three times daily for up to 12 weeks to the affected knee (96668,97537). Some studies have used ginger essential oil in a massage oil, alone or with sweet orange essential oil or standard therapy, twice weekly for 3 or 6 weeks (20341,97542).
• Pregnancy-induced nausea and vomiting. Oral ginger seems to reduce the severity of nausea and vomiting in some people during pregnancy. Ginger seems to be more effective than placebo, comparable to vitamin B6 or dimenhydrinate, and less effective than metoclopramide. Details: Although most clinical studies are small and have methodological limitations, the available research shows that ginger is more effective than placebo, and comparable to vitamin B6 or dimenhydrinate (721,1922,5343,11346,13071,16306,20312,20315,90103,91201,102462). Although ginger is comparable to dimenhydrinate for reducing symptoms of morning sickness, it seems to take about 3 days to reduce vomiting episodes compared to 1 day with dimenhydrinate (16305). In addition, clinical research shows that ginger is less effective than metoclopramide at relieving nausea and vomiting associated with pregnancy (20315). Ginger doses of 500 to 2500 mg daily, divided into two to four daily doses for 3 days to 3 weeks, have been used in clinical research (721,5343,16305,16306,20312,20315,90103,91201). The American College of Obstetrics and Gynecology (ACOG) considers ginger capsules 250 mg 4 times daily a first-line nonpharmacological treatment option for pregnancy-induced nausea based on limited evidence. However, there is no evidence that ginger reduces vomiting (111601).

POSSIBLY INEFFECTIVE

• Chemotherapy-induced nausea and vomiting (CINV). Most clinical research shows that oral ginger does not reduce acute or delayed CINV. The effect of ginger might depend on the dose, the other antiemetics used, or the specific chemotherapy regimen. Details: Most clinical research shows that taking ginger as adjunct to adequate antiemetic therapy does not reduce DELAYED CINV when compared with antiemetic therapy alone (20316,96260,89891,96675,97538,97541,101760,102461,113616). Clinical research from meta-analyses and most individual clinical studies also show that taking ginger 0.5-3.5 grams as an adjunct to standard antiemetic therapy does not reduce the incidence or severity of ACUTE CINV when compared with antiemetic therapy alone (89891,96675,101760,102461,102466,113616). However, conflicting results exist from some individual clinical studies (20316,102466). These individual studies evaluated powdered ginger root or liquid extract of ginger root 0.5-2 grams taken in two to four divided doses daily, starting on either the day of or 3 days before chemotherapy and continuing for 3-5 days after chemotherapy initiation (20316,102466). Also, one small study shows that ginger in doses of 1 gram or less for more than 3 days reduces the likelihood of acute vomiting by 60% (101760). More research is needed to confirm the efficacy of this lower dose. Reasons for the conflicting results are unclear, but several theories have been postulated. One theory is that ginger might help reduce CINV associated with some, but not all, chemotherapy regimens. One preliminary clinical study shows that ginger 500 mg twice daily for 3 days reduces vomiting in patients receiving cyclophosphamide and doxorubicin, but not in patients also receiving 5-fluorouracil or docetaxel (96251). However, since there is limited evidence supporting this theory, additional research is needed to confirm. Another theory is that ginger helps when used with certain antiemetic drugs, but not others. For example, ginger seems to help in cases when optimal antiemetic therapy, such as 5-HT3 receptor antagonists, is not available. Small clinical studies show that ginger reduces the severity of acute nausea when compared with prochlorperazine or metoclopramide, both of which are suboptimal antiemetic therapy for CINV (89891). Another small study shows that ginger is comparable to metoclopramide for improving delayed chemotherapy-induced nausea (13244). On the other hand, several studies show that taking ginger 0.5-2 grams daily along with antiemetic therapy that includes aprepitant does NOT improve acute or delayed CINV (20318,89891,96251,96675). In fact, one study found an association between concomitant use of ginger 2 grams daily with aprepitant and worsened severity of delayed nausea. Ginger is hypothesized to decrease the absorption of aprepitant and reduce its effectiveness for delayed nausea (20318,96675). However, this effect has not been replicated, and aprepitant serum levels were not measured to confirm this hypothesis. Finally, many of the studies showing a benefit of ginger for CINV when used as an adjunct to standard antiemetic therapy are considered to be methodologically flawed (20317,96252,96677). For instance, one study using powdered ginger root 1-2 grams daily during the first three days of chemotherapy in children and adults (20317) has been criticized for inaccurately representing data (89891). Other studies of ginger 500 mg twice daily for up to 10 days used questionable methods to measure outcomes and usually did not differentiate between acute and delayed CINV (96252,96677). Ginger essential oil aromatherapy has also been evaluated. One small study shows that using two drops of ginger essential oil on an aromatherapy necklace for 2 minutes daily for 5 days, starting on the first day of chemotherapy, reduces acute nausea, but not vomiting or delayed nausea, when compared with placebo in females with breast cancer taking standard antiemetics including granisetron, dexamethasone, and metoclopramide (96256).
• Exercise-induced muscle soreness. Most research shows that oral ginger in single or multiple doses does not prevent or treat exercise-induced muscle soreness. Details: Two small studies in healthy adults show that single doses of ginger supplements do not seem to reduce muscle soreness from exercise. Taking capsules of ground ginger 2 grams, 30 minutes before a 30-minute cycling bout, or 24-48 hours after eccentric exercise, does not reduce muscle pain during exercise or within one hour of ingestion when compared with placebo (17932,17934). Taking multiple doses also does not seem to help. One small study in healthy adults shows that taking capsules with ginger powder 4 grams daily for 5 days before high-intensity eccentric exercise does not reduce muscle soreness over 4 days when compared with placebo (96258). Another small study in healthy adults shows that taking capsules of heated or raw ground ginger 2 grams daily for 8 days prior to eccentric exercise, and continuing supplementation for 3 more days, might modestly reduce muscle soreness 24 hours post-exercise, but not at later time points, when compared with placebo (17933,96258). Ginger has also been tested in combination with other ingredients. One small study in healthy adults shows that taking a specific combination product (ReWin(d), Natural Origins) containing a 4:3 ratio of ginger and annatto powder, 2 grams in divided doses daily for 4 weeks before eccentric exercise and continuing for 3 days after exercise, may modestly reduce muscle pain 48 hours after exercise but not at other time points (105057). This study was funded by the supplement manufacturer.
• Motion sickness. Most research shows that oral ginger does not prevent or treat motion sickness. Details: Most clinical research shows that taking ginger 500-1000 mg up to 4 hours prior to travel does not prevent motion sickness (7624,7625,20330,20331). Some patients report subjective feelings of improvement, but in many studies objective measures did not significantly improve (7400). However, one clinical trial suggests that ginger is more effective than dimenhydrinate at reducing gastrointestinal distress associated with motion sickness (20332). Another clinical study seems to show that taking ginger 1-2 grams as a single dose reduces nausea severity and increases the latency before the onset of nausea caused by simulated motion sickness when compared to baseline (20333). The validity of this finding is limited by the lack of a comparator group.

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Acute respiratory distress syndrome (ARDS). Some small clinical studies show that giving ginger with tube feeds to hospitalized patients might reduce the duration of serious sequelae from ARDS. Details: A small clinical trial in adults with ARDS shows that administering ginger extract 120 mg in three divided doses daily via nasogastric tubing for 21 days increases the number of ventilator-free days and the amount of feeding tolerated and decreases the number of intensive care unit (ICU) days when compared with placebo. However, it does not seem to improve overall mortality (20343). Also, another small clinical study shows that adding ginger extract 120 mg to tube feeds in three divided doses daily for 8-21 days improves blood oxygen levels by 13% to 20%, as well as the ability of the lungs to expand by 17%, when compared with a coconut oil placebo. The duration of mechanical ventilation and stay in the ICU also improved. However, ginger does not affect other measurements of lung function or physical organ damage in these patients (89886).
• Allergic rhinitis (hay fever). It is unclear if oral ginger is beneficial in allergic rhinitis. Details: A small clinical trial shows that taking ginger extract 500 mg daily for 6 weeks is as effective as loratadine 10 mg daily for reducing nasal symptoms of allergic rhinitis (103359).
• Antiretroviral-induced nausea and vomiting. Oral ginger seems to improve nausea and vomiting in patients using antiretroviral agents. Details: A small clinical study in patients with HIV shows that taking ginger 0.5 grams twice daily, 30 minutes prior to each dose of antiretroviral for 14 days, reduces the relative likelihood of nausea and vomiting by about 63% and 79%, respectively, when compared with placebo (89887).
• Asthma. Although there has been interest in using oral ginger for asthma, there is insufficient reliable information about the clinical effects of ginger for this condition.
• Back pain. Although there has been interest in using oral ginger for back pain, there is insufficient reliable information about the clinical effects of ginger for this condition.
• Burns. Although there has been interest in using topical ginger for burns, there is insufficient reliable information about the clinical effects of ginger for this condition.
• Cancer-related anorexia. It is unclear if oral ginger improves appetite in people with cancer-related anorexia. Details: A small clinical study in patients with cancer-related anorexia and cachexia shows that taking a capsule containing ginger 1650 mg daily for 14 days improves nausea, appetite, reflux, dysmotility, and other gastrointestinal symptoms when compared to baseline (102460). The validity of these findings is limited by the lack of comparator group.
• Chronic obstructive pulmonary disease (COPD). Oral ginger has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Clinical research shows that taking two capsules of a specific combination product (AKL1, AKL International Ltd.) containing ginkgo extract, ginger, and Picrorhiza kurroa twice daily for 8 weeks does not improve respiratory symptoms when compared with placebo in patients with COPD (89702). Another moderate-sized clinical study in adults with COPD shows that taking a combination product containing extracts of ginger, alpinia, cardamom, cinnamon, and saffron in honey 3 times daily for 8 weeks improves confidence in leaving home and the ratio of forced exploratory volume per second to forced vital capacity of the lungs (FEV1/FVC) when compared with placebo. However, the combination product does not improve most measures of respiratory function or symptoms such as cough, phlegm, chest tightness, dyspnea, reduced energy levels, sleeping disorders, or activity limitations when compared with placebo (111542). It is unclear if these effects are due to ginger, other ingredients, or the combination.
• Colic. Although there has been interest in using oral ginger for colic, there is insufficient reliable information about the clinical effects of ginger for this condition.
• Constipation. Although there has been interest in using oral ginger for constipation, there is insufficient reliable information about the clinical effects of ginger for this condition.
• Coronavirus disease 2019 (COVID-19). It is unclear whether oral ginger is beneficial for patients with COVID-19. Details: Clinical research in adults hospitalized with asymptomatic COVID-19 infection shows that taking ginger 1.5 grams twice daily orally until hospital discharge reduces length of stay from around 8.5 days to 6 days, when compared with placebo. The strongest effect is seen in males over 60 years of age (110005). The relevance of these results is reduced by a lack of blinding, and the fact that the subjects were initially asymptomatic. The efficacy of ginger for treating COVID-19 has also been evaluated in combination with other ingredients. In adults with uncomplicated, moderate COVID-19, taking a combination of ginger, turmeric, ashwagandha, and boswellia (BV-4051, Artovid-20), 1776 mg twice daily orally for 14 days in addition to standard care and starting 48-96 hours after symptom onset, reduces the mean duration of symptoms from about 8 days to 7 days, when compared with placebo (109899). A small open-label study in adults with confirmed mild to moderate COVID-19 shows that taking ginger 1000 mg and ashwagandha 500 mg twice daily for 15 days, along with conventional therapy, leads to a 13.8-fold and 2.6-fold increase in the relative rate of clinical cure at 7 days and 15 days, respectively, when compared with conventional therapy alone. Taking this combination also appears to reduce time to recovery by around 6 days but does not improve the rate of negative COVID-19 tests, chest imaging findings, viral clearance, serum antibodies, or other measures of disease progression when compared with conventional therapy alone (112094). The validity of these findings is limited by a lack of blinding, and the study may have been inadequately powered to detect a difference between groups. Additionally, it is unclear if these effects are due to ginger, ashwagandha, or the combination.
• Diabetes. Some preliminary clinical studies suggest that oral ginger might have a small beneficial effect on glycemic control in patients with type 2 diabetes or gestational diabetes. Details: Meta-analyses of several small clinical trials in adults with type 2 diabetes show that taking ginger 1200-3000 mg daily for 8-13 weeks reduces glycated hemoglobin (HbA1c) by around 0.6% to 1% and fasting blood glucose by 19-21 mg/dL when compared with placebo (96680,107898). Additionally, a small clinical study in adults with diabetes on hemodialysis for end stage renal disease shows that taking ginger powder 2000 mg daily for 8 weeks reduces fasting blood glucose and measures of insulin resistance, but not serum insulin levels, when compared with placebo (111543). In patients with gestational diabetes at weeks 24-28 of pregnancy, clinical research shows that taking ginger 1500 mg daily in three divided doses for 6 weeks reduces fasting blood glucose, insulin levels, and measures of insulin resistance by a small amount when compared with placebo, with no effect on postprandial glucose levels (103358).
• Diarrhea. Although there has been interest in using oral ginger for various types of diarrhea, including cholera and acute bacterial dysentery, there is insufficient reliable information about the clinical effects of ginger for these conditions.
• Dry mouth. It is unclear if rinsing the mouth with ginger extract is beneficial for dry mouth. Details: In patients with dry mouth related to type 2 diabetes, clinical research shows that use of a ginger extract 25% mouthwash 20 mL three times daily for 14 days modestly reduces symptoms of dry mouth when compared with rinsing with a saline control mouthwash (106068). Although this study was indicated as being triple-blind, it is unclear how the taste of ginger was masked.
• Dyspepsia. It is unclear if oral ginger is beneficial for dyspepsia. Details: In patients with dyspepsia, a small clinical trial shows that a single dose of ginger root powder 1.2 grams, taken 1 hour prior to eating, does not reduce abdominal discomfort when compared with placebo. However, it increases the rate of gastric emptying (20325).
• Erectile dysfunction (ED). It is unclear if oral ginger is beneficial for erectile dysfunction. Details: Preliminary clinical research in middle-aged males with ED shows that taking two capsules of a specific combination product (Revactin, MD Concepts LLC) containing ginger root 250 mg, muira puama 250 mg, guarana 250 mg, and L-citrulline 800 mg twice daily for 3 months improves scores related to erectile function and intercourse satisfaction, but does not improve sexual desire or orgasmic function scores, when compared to baseline (103224). This study is limited by the lack of a placebo control, the use of per-protocol analysis, and a high dropout rate. In fact, 44% of patients withdrew in order to resume use of phosphodiesterase type 5 (PDE5) inhibitors. Further, it is unclear if these effects are due to ginger, other ingredients, or the combination.
• Gastroenteritis-associated nausea and vomiting. It is unclear if oral ginger is beneficial for children with gastroenteritis-associated vomiting. Details: In children aged 1-10 years with acute gastroenteritis-associated vomiting, clinical research shows that taking a single dose of ginger reduces the risk of vomiting at least once in the subsequent 8 hours by 20% when compared with placebo. The incidence of vomiting over the next 24 and 48 hours was also modestly reduced. The children were given 20 drops of ginger equivalent to 10 mg immediately, followed by every 8 hours until cessation of vomiting. All children were offered hypotonic oral rehydration solution (ORS) 30 minutes after the first dose (106076). The number of children accepting ORS, and the quantity of ORS consumed, was less in the group receiving placebo. It is unclear if this affected the outcomes of this study. Also, the incidence or severity of nausea was not investigated.
• Hangover. It is unclear if oral ginger is beneficial for managing symptoms of hangover. Details: Preliminary clinical research shows that use of a decoction containing a combination of ginger 6 grams, pith of Citrus tangerine 3 grams, and brown sugar decreases symptoms of alcohol hangovers, including nausea, vomiting, and diarrhea, when compared with placebo. The decoction was taken once 5 hours prior to drinking alcohol or four times after drinking alcohol (20320).
• Hyperlipidemia. Oral ginger may be modestly beneficial for some patients with hyperlipidemia. Details: A meta-analysis of preliminary clinical research in adults with and without hyperlipidemia shows that taking ginger 200-3000 mg orally daily for 2-24 weeks reduces triglyceride and low-density lipoprotein cholesterol levels by 12 mg/dL and 5 mg/dL, respectively, and increases high-density lipoprotein cholesterol levels by 1 mg/dL when compared with placebo (109521). However, the validity of this study is limited by high heterogeneity. A clinical study in adults with hyperlipidemia shows that taking ginger powder 1 gram three times daily for 45 days reduces triglyceride and cholesterol levels by an additional 36% and 90%, respectively, when compared with placebo (20327).
• Hypertension. It is unclear if oral ginger is beneficial for lowering blood pressure. Details: A preliminary clinical study in patients with diabetes and elevated systolic blood pressure shows that drinking black tea containing ginger 3 grams three times daily for 8 weeks does not reduce blood pressure by a clinically significant amount when compared with plain black tea (96669).
• Hypothyroidism. It is unclear if oral ginger is beneficial in patients with hypothyroidism. Details: A small clinical study in patients with primary hypothyroidism who are stabilized on thyroid hormone therapy shows that taking ginger powder 500 mg twice daily for 30 days improves symptoms associated with hypothyroidism, including cold intolerance, constipation, dizziness, dry skin, weight gain, and concentration and memory issues, when compared with placebo. However, ginger supplementation does not seem to improve hair loss, hearing, nail fragility, speech, or feelings of depression in these patients (107903).
• Insect bite. It is unclear if topical ginger is beneficial for reducing the size of insect bites. Details: Preliminary clinical research shows that a topical application of Trikatu, which contains ginger, long pepper, and black pepper extracts with 0.074% piperine and 0.046% gingerol, does not reduce the papule size associated with mosquito bites when compared with a control compound containing the same base ingredients of camphor 2%, menthol 2%, and eucalyptus oil 4% (89893).
• Intraoperative nausea and vomiting (IONV). It is unclear if oral ginger is beneficial for preventing IONV. Details: Clinical research in individuals undergoing elective C-section and receiving cimetidine and metoclopramide, shows that taking ginger 1 gram orally 30 minutes prior to anesthesia reduces the number of episodes of intraoperative nausea, but not vomiting, when compared with placebo (89890). In other clinical research in adults undergoing elective surgical procedures, adding ginger to a high calorie drink consumed pre-operatively reduces the incidence of nausea from 40% to 10%, and the incidence of vomiting from 25% to 10% when compared with the high calorie drink alone (110007). The validity of these results is unclear as only patients were blinded to the treatment group.
• Irritable bowel syndrome (IBS). Oral ginger might reduce symptoms of IBS when used in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical trial shows that taking ginger 1-2 grams daily for 28 days does not improve symptoms or the number of responders when compared with placebo (90102). However, some research shows that ginger might be beneficial in some patients when used along with other herbal ingredients. Taking a capsule containing ginger, boswellia, and yarrow three times daily for 30 days reduces the frequency and severity of abdominal pain, as well as the severity of bloating, when compared with placebo in females, but not males, with mild to moderate IBS (96673). Another clinical study shows that taking an herbal mixture containing ginger, English horsemint, and purple nut sedge tuber three times daily for 8 weeks improves IBS symptoms including abdominal pain, stool frequency, stool consistency, incomplete evacuation, and urgency, when compared to baseline; these improvements are similar to those achieved by taking mebeverine 135 mg three times daily (89900). However, it is unclear if these effects are due to ginger, other ingredients, or the combination.
• Joint pain. Oral ginger has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Clinical research shows that taking a specific combination product (Instaflex Joint Support, Direct Digital) containing glucosamine sulfate 1500 mg, methylsufonlylmethane 500 mg, white willow bark extract 250 mg, ginger root concentrate 50 mg, Boswellia extract 125 mg, turmeric root extract 50 mg, cayenne 40 m H.U. 50 mg, and hyaluronic acid 4 mg in three divided doses daily for 8 weeks reduces joint pain severity by 37% compared to only 16% with placebo. However, it does not improve joint stiffness or function when compared with placebo (89560). It is unclear if these effects are due to ginger, other ingredients, or the combination.
• Menorrhagia. It is unclear if oral ginger is beneficial for menorrhagia. Details: Preliminary clinical research in healthy adults experiencing heavy menstrual bleeding shows that taking ginger 250 mg three times daily for 4 days, starting the day prior to menstruation, and repeating for three menstrual cycles, reduces the amount of menstrual bleeding when compared with placebo (96672).
• Menopausal symptoms. Although there has been interest in using oral ginger for menopausal symptoms such as insomnia, there is insufficient reliable information about the clinical effects of ginger for this purpose.
• Migraine headache. Small clinical studies suggest that oral ginger may modestly reduce migraine pain severity and duration. However, taking ginger doesn't seem to PREVENT migraines. Details: Ginger does not seem to be effective for the prevention of migraines. Clinical research in patients with episodic migraine shows that taking ginger extract 200 mg three times daily for 3 months does not reduce the number of migraine attacks, the use of analgesics, or the number of days with pain, any more than taking placebo (101761). However, ginger may be beneficial for the treatment of migraine. Clinical research shows that taking ginger extract 400 mg orally in the emergency room along with intravenous ketoprofen 100 mg reduces pain over the next 2 hours when compared with ketoprofen and placebo. This combination also resulted in an overall better response with a higher likelihood of having no or mild pain with treatment (101762). Taking ginger 250 mg at the onset of a common migraine headache seems to be as effective as taking sumatriptan 50 mg for reducing headache severity within two hours of treatment (89894). Furthermore, a combination of ginger and feverfew (GelStat Migraine, GelStat Corporation; LipiGesic M, PuraMed BioScience), administered sublingually at the onset of a migraine attack, decreases the duration and intensity of migraine pain when compared with placebo (19357,22602). It is unclear if these effects are due to ginger, feverfew, or the combination. Feverfew alone has demonstrated some benefit in treating migraines.
• Multiple sclerosis (MS). It is unclear if oral ginger is beneficial for MS. Details: A small clinical study in adults with MS shows that taking ginger 500 mg three times daily for 12 weeks reduces disability scores and improves physical and psychological quality of life scores when compared with placebo (111541). Another small clinical study in adults with relapsing-remitting MS shows that taking ginger 500 mg three times daily for 12 weeks reduces the frequency and severity of nausea and constipation and the severity but not frequency of bloating when compared with placebo. However, no improvement was noted in other gastrointestinal symptoms of MS including abdominal pain, anorexia, diarrhea, dysphagia, gas, or heartburn (113614).
• Nonalcoholic fatty liver disease (NAFLD). It is unclear if oral ginger is beneficial for NAFLD. Details: A small clinical study in patients with NAFLD shows that taking ginger 1000 mg twice daily for 12 weeks improves liver steatosis scores but not liver fibrosis scores when compared with placebo. Ginger also modestly improves levels of alanine aminotransferase and gamma-glutamyl transferase but not aspartate aminotransferase (113615). However, it is unclear whether any improvements are clinically significant. Another small clinical study in patients with NAFLD shows that taking ginger root 1500 mg daily for 12 weeks reduces low-density lipoprotein (LDL) cholesterol and fasting blood glucose levels, but does not affect triglycerides, high-density lipoprotein (HDL) cholesterol, insulin resistance, blood pressure, or fatty liver index, when compared with placebo (102465).
• Obesity. Oral ginger has primarily been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Although some individual research disagrees (40802), a meta-analysis and most individual clinical trials show that taking ginger alone or with other ingredients does not reduce weight by a clinically significant amount when compared with placebo in overweight or obese individuals (20346,20347,96676,109521). Ginger has been taken alone or in combination with green tea and capsaicin; rhubarb, astragalus, red sage, turmeric, and gallic acid (Number Ten); or raspberry ketone (Razberi K, Integrity Nutraceuticals), caffeine, capsicum extract (Capsimax, OmniActive Health Technologies), bitter orange fruit (Advantra Z, Nutratech Inc), L-theanine, and black pepper fruit extract (Biperine, Sabinsa Corporation) (Prograde Metabolism) (20346,20347,40802,96676). Due to the various other ingredients contained in available formulations, any effect from ginger is unclear.
• Parturition. It is unclear if bathing in a ginger bath is beneficial for shortening the duration of labor. Details: Preliminary clinical research shows that bathing in 228 liters of water containing 4 drops of ginger essential oil does not shorten the duration of labor when compared with a regular bath (20345).
• Polycystic ovary syndrome (PCOS). It is unclear if oral ginger is beneficial for females with PCOS. Details: Preliminary clinical research in females with PCOS shows that taking ginger 500 mg three times daily orally for 8 weeks decreases body weight, body mass index, and levels of follicle stimulating hormone and luteinizing hormone, when compared with placebo. It does not affect testosterone levels (110006).
• Postoperative nausea and vomiting (PONV). Evidence for the use of oral ginger for preventing PONV is inconclusive and conflicting. Reasons for the conflicting findings may relate to the ginger formulation used and the outcomes measured. It is unclear if ginger aromatherapy is beneficial for PONV. Details: Some individual clinical studies, as well as a large, recent meta-analysis of the available clinical research, show that taking ginger by mouth 1 hour prior to surgery does not reduce the incidence of 24-hour PONV (3452,3453,17369,99445). Also, the meta-analysis found that, although ginger reduces the severity of PONV when measured on a visual analogue scale (VAS), it does not reduce the severity of PONV when measured on a verbal descriptive scale (VDS). Furthermore, ginger does not reduce the use of rescue antiemetic medications (99445). However, some small, individual clinical studies and a meta-analysis of older clinical research show that taking ginger by mouth prior to surgery reduces the incidence of 24-hour PONV by up to 16% to 38% (722,723,1919,13237,20336,20338,20339). In addition, large clinical trials show that the frequency and severity of PONV 2-6 hours after surgery are similar when ginger 1 gram is given orally or when medications such as metoclopramide or dexmedetomidine are given intravenously prior to undergoing anesthesia (103356,103360). However, taking ginger prior to general anesthesia, in combination with other antiemetics like dexamethasone or cimetidine and metoclopramide, does not seem to reduce nausea and vomiting when compared with the other medications alone (20337,89890). In contrast, other research shows that powdered ginger 1-2 grams 30-60 minutes before induction of anesthesia has been used in most studies showing benefit, occasionally followed by 1 gram of ginger administered two hours after surgery (722,723,13237,20336,20338,103356,103360). Ginger aromatherapy has also been evaluated for the prevention of PONV. Application of 5% ginger essential oil to the wrists of patients prior to the induction of general anesthesia seems to prevent PONV in approximately 80% of treated patients (20334). Also, use of ginger essential oil aromatherapy on a gauze pad results in nausea relief in approximately 67% of patients compared with 40% in the placebo group; however, a blend of essential oils including ginger, spearmint, peppermint, and cardamom, results in nausea relief in 82% of patients (89888).These conflicting findings may be due to differences in outcome measures and the chemical compositions of ginger preparations used in the various clinical studies. Some evidence suggests that the efficacy of ginger for preventing PONV differs based on the formulation used. A network meta-analysis of 18 studies evaluating various ginger preparations, including ginger oil, ginger powder, ginger extract, and a combination of ginger powder and antiemetics, for the prevention of PONV suggests that ginger powder and ginger oil are the most effective formulations for preventing nausea and vomiting, respectively. The analysis also shows that while no ginger formulation is superior to another for the prevention of nausea, ginger powder and ginger oil have a lower risk of postoperative vomiting when compared with ginger extract. A subgroup analysis suggests that ginger seems to be most effective in adults over 30 years of age, when administered preoperatively, and when used for gastrointestinal, hepatobiliary, obstetric, or ophthalmic surgeries (112108).
• Postoperative recovery. It is unclear if oral ginger is beneficial for postoperative recovery. Details: One preliminary clinical study in adults who had a tonsillectomy shows that taking a specific ginger supplement (Solgar, Leonia) 500 mg twice daily for 7 days along with acetaminophen and antibiotics modestly improves pain and wound healing when compared with acetaminophen and antibiotics alone (96674).
• Postpartum complications. It is unclear if oral ginger is beneficial in patients with postpartum pain. Details: A small clinical study in patients recovering from vaginal delivery shows that taking ginger powder 500 mg 8-hours post-delivery, followed by 250 mg every 8 hours thereafter for 24 hours, reduces postpartum pain by nearly 1 point on a 10-point rating scale when compared with placebo (107904). It is unclear if this improvement would be considered clinically relevant.
• Radiation-induced nausea and vomiting. It is unclear if oral ginger is beneficial in patients with radiation-induced nausea and vomiting. Details: A very small study in adults with cervical cancer undergoing treatment with cisplatin and radiotherapy shows that taking ginger 250-500 mg twice daily for 6 weeks in addition to standard antiemetic therapy does not reduce acute or delayed nausea and vomiting when compared with antiemetic therapy alone (113616).
• Rheumatoid arthritis (RA). One small clinical study suggests that oral ginger may improve some symptoms of RA. Details: Preliminary clinical research in adults with RA shows that taking ginger powder 1500 mg daily for 12 weeks improves disease activity on the Disease Activity Score-28 when compared with placebo (100697).
• Smoking cessation. Oral ginger has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A moderate-sized clinical study in adults with a history of smoking 5 or more cigarettes daily for at least 3 years shows that taking a specific combination product containing ginger 25 mg, turmeric, ashwagandha, Indian gooseberry, tribulus, bacopa, Albizia lebbeck, licorice, clove, cowhage, holy basil, and turmeric (Smotect, Smotect India) daily for 3 months reduces the number of cigarettes smoked by approximately 3 per day when compared with placebo. This product also reduces levels of alveolar carbon monoxide and carboxyhemoglobin but does not improve lung capacity (112115). However, only data from patients who completed treatment were analyzed, which limits the validity of this study. It is also unclear if these effects are due to ginger, other ingredients, or the combination.
• Swallowing dysfunction. The effects of oral ginger for treating swallowing dysfunction are inconclusive. Reasons for the conflicting findings may relate to the route of administration or the number of treatments provided. Details: Clinical research shows that applying a spray containing ginger and clematix root (Tongyan) to the oropharynx for 28 days is more effective than placebo at treating grade 2 or 3 dysphagia in stroke victims. However, there does not seem to be a beneficial effect in patients with grade 1 dysphagia (20342). Other clinical research in elderly patients with dysphagia shows that taking a single dose of ginger 2 mg orally does not improve swallowing but increases saliva (96671). It is possible that a single dose of ginger is not enough to improve swallowing function.
• Toxin-induced liver damage. Oral ginger might help to prevent liver damage in patients using antimycobacterial drugs. Details: Preliminary clinical research shows that a specific ginger supplement (Zintoma, Goldaru) 500 mg taken 30 minutes prior to antimycobacterial drugs daily for 4 weeks reduces the percentage of patients experiencing an increase in liver function enzymes to greater than five times the upper limit of normal by 54% when compared with placebo. Antimycobacterial drugs used for tuberculosis in the study included isoniazid 5 mg/kg, rifampin 10 mg/kg, ethambutol 15 mg/kg, and pyrazinamide 25 mg/kg daily (96670).
• Traumatic brain injury (TBI). Oral ginger has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary research in young adults with subjective memory dysfunction associated with mild TBI, shows that taking a combination of ginger 36 mg and boswellia 360 mg (Memoral) every 8 hours orally for one month improves scores for some, but not all, parameters on an auditory-visual learning test performed at one and three months, when compared with placebo. Total learning scores increased by about 7.5 points with the ginger combination product, compared with 4 points for placebo (110132). It is unclear if these effects are due to ginger, boswellia, or the combination.
• Ulcerative colitis. It is unclear if oral ginger is beneficial for improving symptoms of ulcerative colitis. Details: Preliminary clinical research in adults with ulcerative colitis shows that taking ginger powder 1000 mg twice daily for 12 weeks improves disease activity as measured by the Simple Clinical Colitis Activity Index Questionnaire when compared with taking placebo. However, taking ginger did not improve quality of life, stool frequency, bowel distress, or flatulence when compared with placebo (100694). It is possible that this study was not adequately powered to detect a difference in these secondary outcomes.
• Upper respiratory tract infection (URTI). Although there has been interest in using oral ginger for various upper respiratory tract infections, there is insufficient reliable information about the clinical effects of ginger for this condition.
• Vertigo. It is unclear if oral ginger is beneficial for improving symptoms of vertigo. Details: A small clinical study shows that taking 1 gram of ginger orally as a single dose prior to stimulated vertigo seems to reduce symptoms of vertigo, including nausea, when compared with placebo. However, it does not seem to reduce nystagmus (7623). More evidence is needed to rate ginger for these uses.

(Read more about GINGER)

EFFECTIVE

• Anemia of chronic disease. Oral and intravenous iron in combination with erythropoiesis-stimulating agents (ESAs) are effective for treating anemia of chronic disease. Details: Iron supplementation with ESAs is effective for treating anemia associated with chronic kidney disease (CKD) or chemotherapy. During therapy with ESAs, iron levels should be monitored and supplementation provided as needed to ensure that the response is not limited by lack of iron for erythropoiesis (1087,1091,20110,20111,110192). Research shows that intravenous iron appears to be more effective than oral supplements for this purpose (20112,20113). In patients with CKD, intravenous iron at total doses from 2232 mg over 6 months to 1020 mg over one week increases hemoglobin levels more than oral doses of 4-6 mg/kg daily or 325 mg daily for up to 6 months (20112). Some research has evaluated the effect of intravenous or oral iron in patients not treated with ESAs. In patients with cancer or CKD, oral iron supplements have been shown to improve iron status (110184,110192). However, overall benefits of iron alone remain unclear in treated or untreated patients with cancer and more research is needed to rule out an increase in mortality and to determine any effect on blood transfusion requirements (110192). Preliminary clinical research shows that children aged 6 months to 10 years with HIV and anemia who take elemental iron 3 mg/kg daily along with a multivitamin for 3 months have a 41% lower chance of having persistent anemia at 3 months when compared with multivitamins alone (95432).
• Iron deficiency anemia. Oral and intravenous iron are effective for treating or preventing iron deficiency anemia. The benefits of iron supplementation in people with iron deficiency without anemia are unclear. Details: Oral iron supplements, mainly as ferrous sulfate, are effective for treating and preventing iron deficiency anemia in adults, children, and infants (1089,7135,17495,17496,17497,103806,20114,20115,91183,96621)(104680,104681,112601). Other forms are also effective, including sodium iron ethylenediaminetetra-acetate (NaFeEDTA), iron(III)-hydroxide polymaltose complex (IPC), iron protein succinylate, iron bisglycinate, and lactoferrin with iron (20117,20118,110189). Treatment with iron supplements should increase hemoglobin levels by 1 gram/dL every 2-3 weeks. However, even after hemoglobin has normalized, it may take up to 4 months for iron stores to be replenished (17497). Historically, treatment of iron deficiency anemia with oral iron supplements has typically consisted of a daily dosing regimen, often taken in divided doses to reduce adverse effects. In more recent years, however, intermittent iron supplementation (1-3 doses/week) has become preferred for some patients, particularly those with mild anemia, due to better absorption and a possible reduction in side effects compared to daily dosing. One small clinical study shows that taking ferrous sulfate 60 mg on alternate days in single doses improves iron absorption when compared to once daily dosing (96630). Another small clinical study in females with iron-deficiency anemia shows that fractional iron absorption is 40% to 50% higher with alternate-day dosing compared with daily dosing. Furthermore, total iron absorption was shown to be similar for alternate day dosing of elemental iron 200 mg compared with daily dosing of 100 mg, but the incidence of gastrointestinal adverse effects may be lower for the alternate day dosing regimen (101514). A meta-analysis of 25 clinical trials, including 10,996 menstruating females with or without pre-existing iron deficiency and/or anemia, shows that intermittent iron reduces the risk of anemia and increases hemoglobin and serum ferritin when compared with placebo or no intervention. This meta-analysis did not identify differences in the risk of anemia, hemoglobin, or serum ferritin between intermittent and daily iron supplementation. However, it did show that females receiving intermittent dosing had a 59% reduction in the risk for adverse effects. The validity of these findings is limited by significant heterogeneity in the enrolled populations and selected dosing strategies, including frequency of intermittent dosing, total weekly dose, and duration of follow-up. In addition, the subgroup analyses performed by baseline anemia, hemoglobin, and serum ferritin, as well as duration of follow-up, showed differing overall conclusions when comparing intermittent and daily iron supplementation. While intermittent dosing appears to be beneficial when compared with daily dosing for some patients with iron deficiency anemia, intermittent dosing may be less effective than daily iron supplementation in some patients (103806). For patients with severe anemia, twice daily dosing may be preferred to alternate day dosing due to faster response. A small clinical study in patients with iron deficiency anemia shows that taking ferrous sulfate 200 mg twice daily is more effective at increasing hemoglobin levels by 3 weeks when compared with ferrous sulfate 400 mg taken on alternate days in single doses (102864). Intermittent iron supplementation has also been investigated in children. A meta-analysis of clinical research in children and adolescents with or without pre-existing iron deficiency and/or anemia shows that taking iron supplements 1-2 times weekly is similarly effective as 3-7 times weekly for decreasing iron deficiency and iron deficiency anemia. However, ferritin and hemoglobin levels increased to a greater extent with 3-7 times weekly supplementation (112601). Blood transfusion may be required for some patients with severe iron deficiency anemia who have symptoms such as dyspnea and fatigue (17497). Intravenous iron should be considered in patients who cannot tolerate oral iron or in patients with chronic bleeding or intestinal malabsorption (17497). Guidelines from the British Society of Gastroenterology recommend treatment with iron while awaiting investigations to rule out gastrointestinal issues in adults in the absence of an alternative explanation. The guidelines recommend ferrous sulfate, fumarate, or gluconate as one tablet daily. If adverse effects occur, intake can be reduced to once every other day, or alternative oral or parenteral sources of iron can be used. Parenteral sources should be used if oral sources are contraindicated or ineffective. Treatment should be monitored and continued after hemoglobin levels are normalized (110193). Iron supplementation may also be beneficial in patients with iron deficiency without anemia, which can cause fatigue and reduced well-being, although guidelines are lacking. A meta-analysis of randomized controlled trials in adults with iron deficiency but not anemia shows that supplemental iron improves iron stores and hemoglobin levels. In addition, iron moderately reduces self-reported fatigue, but not physical capacity, when compared with placebo. Oral ferrous sulfate was used in most studies included in the analysis; however, intravenous or intramuscular iron were also used (104684).
• Pregnancy-related iron deficiency. Oral iron is effective for preventing pregnancy-related iron deficiency. Details: Clinical research shows that taking iron orally at an average daily dose of 20-225 mg of elemental iron increases maternal hemoglobin levels by up to 1 gram/dL when compared with placebo and reduces the risk of maternal anemia by 62% to 100% (20122,20123,20124,110180,110188). Some clinicians may recommend alternating days of iron administration to reduce gastrointestinal adverse effects. A pooled analysis shows that taking iron supplements on alternating days during pregnancy maintains adequate iron intake and reduces gastrointestinal adverse effects when compared with taking iron daily (96625). Various forms of oral iron seem to be equally effective for raising hemoglobin levels (110185,110188). However, in patients with anemia during pregnancy, a meta-analysis of clinical research shows that intravenous iron sucrose and ferric carboxymaltose were more effective than oral ferrous sulfate for improving hemoglobin levels (110185).

POSSIBLY EFFECTIVE

• Breath-holding attacks. Oral iron seems to be effective for reducing the frequency of breath-holding attacks in children with iron deficiency. Details: The incidence of breath-holding attacks is increased in children with iron deficiency or iron deficiency anemia. Most research shows that oral supplementation with ferrous sulfate 3-6 mg/kg daily for 4-16 weeks reduces the frequency of breath-holding attacks in children aged 1-72 months (20128,104682,104683). The best evidence comes from a meta-analysis of one randomized controlled trial and 11 observational single arm studies (104682). In this analysis, approximately 84% of children experienced at least a 50% decreased frequency of breath-holding attacks (104682). Some preliminary clinical research also shows that administering intramuscular iron reduces the frequency of breath-holding attacks and increases remission in children with iron deficiency anemia (20128).
• Cognitive function. Oral iron seems to be effective for improving cognitive function in children and adolescents with iron deficiency. Details: Taking iron orally seems to improve cognitive function in iron-deficient children and adolescents (20121,112600). For example, ferrous sulfate 650 mg twice daily for 8 weeks improved verbal learning and memory in non-anemic iron-deficient adolescent females (1095). Ferrous sulfate 50 mg twice weekly for 16 weeks appeared to improve attention measures in adolescent females with possible anemia (91186). Iron also appears to reverse developmental and learning deficits caused by iron-deficiency in anemic infants (1104). Some clinical research is focused on children and adolescents from low- and middle-income countries. In children aged 5-19 years with or without iron-deficiency anemia, a meta-analysis of clinical research shows that iron supplementation for 3-8 months dose-dependently improves measured intelligence by a modest amount. However, there was no effect on other measures of cognition, including attention or memory (110181). Another meta-analysis of clinical research in school age children shows that taking iron for 2-12 months modestly improves intelligence, attention, and memory, but not educational achievement, when compared with placebo or no intervention. However, sub-analyses show that any benefits are limited to children with anemia (112600).
• Heart failure. Intravenous iron seems to be effective for improving recovery in patients with heart failure and iron deficiency. It is unclear if oral iron is effective. Details: Iron deficiency is common in patients with heart failure (17499,112597,112598,112599). Individual clinical trials and meta-analyses of clinical research in patients with heart failure show that administering intravenous iron, as ferric carboxymaltose, iron dextran, iron isomaltoside, or iron sucrose, for at least 12 weeks modestly improves quality of life, increases exercise capacity, and reduces hospitalizations when compared with placebo or standard care. However, there was no effect on all-cause mortality or cardiovascular mortality (17498,91179,110176,110187,112597,112598,112599). Some individual clinical trials have used intravenous ferric carboxymaltose 200 mg or iron sucrose 200 mg in patients with mild or moderate heart failure and iron deficiency (17498,91179). Guidelines from the British Society of Gastroenterology suggest that treatment with parenteral iron improves symptoms and quality of life in patients with functional iron deficiency related to CHF (110193). Limited research has investigated the effect of oral iron in this population. A small meta-analysis of clinical research shows with low certainty that taking iron orally has beneficial effects on serum ferritin and left ventricular ejection fraction (110178). Most research shows that taking oral iron does not improve hemoglobin levels, quality of life, or exercise capacity when compared with placebo (100970,110178). However, one small clinical trial shows that taking oral iron modestly improves iron status and overall symptoms and increases the 6-minute walking distance by about 46 meters, compared with a reduction of only 14 meters in those taking placebo (110183). Some doses used in individual clinical studies have included iron polysaccharide 150 mg twice daily for 16 weeks and ferrous sulfate 200 mg three times daily for 12 weeks (100970,110183).
• Restless legs syndrome (RLS). Oral and intravenous iron seem to be beneficial for RLS. The American Academy of Neurology recommends a combination of oral ferrous sulfate and vitamin C or intravenous ferric carboxymaltose for patients with RLS. Details: RLS is commonly associated with iron deficiency anemia. Some clinical research shows that taking iron in the form of ferrous sulfate 325 mg twice daily for 12 weeks reduces RLS symptoms comparably to pramipexole. Symptoms such as leg discomfort, need to move, and sleep disturbances improved considerably in about half of the patients taking either treatment (91181). Additional clinical research shows that taking ferrous sulfate 325 mg twice daily along with vitamin C 100 mg twice daily for 12 weeks reduces symptoms of RLS when compared with vitamin C alone in patients with RLS and low-normal serum ferritin levels (94189). Based on these results, clinical practice guidelines by the American Academy of Neurology report that taking this combination of oral ferrous sulfate and vitamin C is likely to improve symptoms in patients with RLS and low-normal serum ferritin (93587). Intravenous iron may also reduce symptoms of RLS. Clinical practice guidelines by the American Academy of Neurology report that two doses of intravenous ferric carboxymaltose 500 mg given 5 days apart are likely to improve symptoms and quality of life within 28 days in patients with moderate to severe RLS, regardless of serum ferritin levels. Intravenous iron sucrose has also been evaluated in patients with RLS, but there is currently insufficient available evidence to support or refute the use of this form of iron for treating RLS (93587).

POSSIBLY INEFFECTIVE

• Athletic performance. Oral iron does not seem to improve athletic performance. Details: A meta-analysis of clinical research in adults of childbearing age shows that iron supplementation improves some exercise performance measures, such as maximal oxygen uptake capacity, but not others, such as time until exhaustion and energy consumption, when compared with control (91184). Another meta-analysis of clinical research in patients with iron deficiency without anemia shows that iron supplementation improves subjective measures of fatigue, but does not improve exercise time to exhaustion or other measures of physical capacity (104684). A small clinical study in healthy children shows that taking iron supplements or consuming food providing iron 30-200 mg daily for 1-2 months improves running performance when compared with placebo. This was demonstrated by reductions of heart rate of 6.6 to 8 beats per minute during the running exercise. One preliminary study included in this analysis also showed that iron supplementation improved treadmill endurance time (20140).
• Child growth. Oral iron does not seem to be beneficial for child growth. Details: Meta-analyses of mainly preliminary clinical research show that oral iron supplementation, at doses averaging 2-80 mg or 1-10 mg/kg elemental iron daily for up to 52 weeks, does not increase growth rate in children (20131,20132,20133,95434).
• Preterm labor. Oral iron does not seem to prevent preterm labor and may actually increase the risk in malaria-endemic regions. Details: A meta-analysis of results from five clinical studies shows that maternal intake of iron as ferrous sulfate 20-60 mg daily for 14-26 weeks starting in the second trimester of pregnancy does not affect the length of gestation or increase birthweight of the infant (95434). In females from a malaria-endemic area who have never been pregnant before, another clinical study shows that taking ferrous gluconate 60 mg and folic acid 2.8 mg weekly, starting before conception and continuing to the first antenatal visit, may more than double the risk of preterm birth, defined as a delivery under 37 weeks gestation, when compared with folic acid alone (100969). Some research suggests that the adverse outcome in this latter study may be explained by a rise in hepcidin levels in pregnant patients with malaria. Hepcidin is a hormone that regulates iron absorption and distribution, and malaria can upregulate hepcidin. High levels of hepcidin can decrease iron absorption, stimulate inflammatory processes, and cause progesterone withdrawal, leading to preterm labor (102863).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• ACE inhibitor-induced cough. It is unclear if oral iron is beneficial in patients with this condition. Details: A small clinical trial shows that taking ferrous sulfate 256 mg daily reduces or eliminates cough induced by ACE inhibitors such as captopril (Capoten), enalapril (Vasotec), lisinopril (Prinivil, Zestril), and others, when compared with placebo (7307).
• Androgenic alopecia. Oral iron has only been evaluated in combination with other ingredients, its effect when used alone is unclear. Details: A moderate-sized clinical study in adults with androgenic alopecia or telogen effluvium shows that taking one tablet daily of a specific product (GFM Oral, Cantabria Labs), providing an unknown dose of iron in combination with selenium, taurine, cysteine, methionine, and hydrolyzed collagen, along with conventional therapy, consisting primarily of finasteride or minoxidil, for 12 weeks improves hair loss when compared with conventional therapy alone (111636). It is unclear if this effect is due to iron, other ingredients, or the combination.
• Attention deficit-hyperactivity disorder (ADHD). It is unclear if oral iron is beneficial in children with ADHD. Details: Three small clinical studies in children with ADHD and iron deficiency shows that taking oral iron improves some measures of ADHD after 1-3 months of treatment when compared with baseline or placebo. These studies used ferrous sulfate 5 mg/kg daily, ferrous sulfate 80 mg daily, ferrous fumarate 200 mg daily for children weighing up to 30 kg, or ferrous fumarate 400 mg daily for children weighing more than 30 kg (1093,16013,110191).
• Child development. It is unclear if oral iron is beneficial for improving development in non-anemic children. Details: Some observational research has found that iron deficiency in infancy is associated with poor verbal performance and social skills in childhood (102862). It is unknown whether iron supplementation can ameliorate these developmental issues. In non-anemic infants and children, preliminary clinical research shows that iron does not improve cognitive performance; the evidence for the benefits of iron on psychomotor development is conflicting (20129,20130,91315,96616,96626).
• Esophageal cancer. It is unclear if oral iron is beneficial for esophageal cancer prevention. Details: Population research has found that taking iron supplements is associated with a 32% lower risk of esophageal adenocarcinoma when compared to never taking iron supplements. However, use of iron supplements is not associated with a lower risk of esophageal squamous cell carcinoma (95435).
• Fatigue. It is unclear if oral iron is beneficial in patients with fatigue due to iron deficiency without anemia. Details: A meta-analysis of mainly preliminary clinical research in adults with iron deficiency without anemia shows that iron reduces self-reported fatigue moderately more than placebo (104684). A specific ferrous sulfate supplement (Tardyferon; Pierre Fabre Médicament) providing 80 mg of elemental iron daily for 4-12 weeks was used in two studies included in this analysis (11406,91188).
• Inflammatory bowel disease (IBD). In patients with active IBD, intravenous iron may be more beneficial than oral iron due to impaired absorption. However, it may also increase the risk of infection in these patients. Details: Since the absorption of oral iron may be impaired in patients with active symptoms of IBD, guidelines from the British Society of Gastroenterology suggest that treatment with parenteral iron may be needed in patients with IBD who have moderate to severe iron-deficiency anemia (110193). However, a meta-analysis of clinical research in this population shows that administering IV iron, usually as iron sucrose or ferric carboxymaltose, increases the risk of infection by 73% when compared with oral iron or no iron (110186).
• Postoperative recovery. It is unclear if intravenous iron is beneficial for recovery following cardiac surgery. Details: A meta-analysis of low- to moderate-quality clinical research in patients with preoperative iron-deficiency anemia shows that treatment with intravenous iron before cardiac surgery does not improve the rate of transfusions or the length of stay in the intensive care unit or hospital when compared with control groups, including placebo, oral iron, or no treatment. Also, a meta-analysis of clinical research shows that intravenous iron does not reduce postoperative mortality rates (110182).
• Postpartum depression. Although there has been interest in using iron for postpartum depression, there is insufficient reliable information about the clinical effects of iron for this condition.
• Prematurity. Enteral iron seems to be beneficial for some measures of development in preterm infants. Details: A meta-analysis of clinical research in preterm or low birthweight infants fed human milk shows that enteral iron supplementation increases linear growth and reduces the risk of anemia when compared with control groups receiving no iron supplementation. However, there was no effect on serum ferritin, weight, head circumference, cognitive development, risk of infection, or risk of necrotising enterocolitis (110177). Additional clinical research in infants born at 24-28 weeks' gestation shows that a higher average enteral iron dose by 60 days of age is positively associated with cognitive performance at 2 years of corrected age. However, this association was not present for iron doses received at 90 days of age (110190). More evidence is needed to rate iron for these uses.

(Read more about IRON)

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Alzheimer disease. It is unclear if oral lion's mane mushroom is beneficial in patients with Alzheimer disease. Details: Preliminary clinical research in patients over 50 years of age with mild Alzheimer disease shows that taking lion's mane mushroom mycelia (standardized to contain 5 mg/gram of erinacrine A) 1.05 grams daily for 49 weeks improves performance of activities of daily living when compared with placebo. It also improves scores on the Mini-Mental State Examination when compared with baseline (105546). The validity of these findings is reduced by the lack of an intention to treat analysis, and the comparison of some outcomes to baseline instead of placebo.
• Anxiety. Although there is interest in using oral lion's mane mushroom for anxiety, there is insufficient reliable information about the clinical effects of lion's mane mushroom for this condition.
• Athletic performance. Although there is interest in using oral lion's mane mushroom for improving athletic performance, there is insufficient reliable information about the clinical effects of lion's mane mushroom for this purpose.
• Cancer. Although there is interest in using oral lion's mane mushroom for cancer, there is insufficient reliable information about the clinical effects of lions mane mushroom for this purpose.
• Cognitive function. Small clinical trials suggest that lion's mane mushroom does not improve cognitive function. Details: A small clinical trial shows that taking lion's mane mushroom 3.2 grams daily for 12 weeks does not improve most measures of cognitive function when compared with placebo in middle aged to older adults (101770). Additional clinical research in younger adults shows that taking lion's mane mushroom 10 grams daily for 4 weeks does not improve markers of cognition during a period of exercise-induced fatigue when compared with taking placebo. The lion's mane product is 50% dried mushroom and 50% extract (111932). These studies were small and may have been underpowered to detect differences.
• Cognitive impairment. It is unclear if oral lion's mane mushroom is beneficial in patients with mild cognitive impairment. Details: One clinical study in Japanese patients aged 50-80 years old with mild cognitive impairment shows that taking lion's mane mushroom powder 1 gram three times daily for 16 weeks increases cognitive function when compared with placebo. However, cognitive function regresses within 4 weeks of treatment termination (91999).
• Coronavirus disease 2019 (COVID-19). Although there has been interest in using oral lion's mane mushroom for COVID-19, there is insufficient reliable information about the clinical effects of lion's mane mushroom for this purpose.
• Dementia. Although there is interest in using oral lion's mane mushroom for dementia, there is insufficient reliable information about the clinical effects of lion's mane mushroom for this condition.
• Depression. It is unclear if oral lion's mane mushroom is beneficial in patients with depression. Details: Preliminary clinical research in perimenopausal patients without a formal diagnosis of depression shows that eating 4 cookies daily, each containing 0.5 grams powdered lion's mane mushroom, for 4 weeks is similarly effective to placebo cookies for reducing scores on a depression scale (105547).
• Diabetes. Although there is interest in using oral lion's mane mushroom for diabetes, there is insufficient reliable information about the clinical effects of lion's mane mushroom for this condition.
• Gastritis. It is unclear if oral lion's mane mushroom is beneficial in patients with chronic atrophic gastritis. Details: Preliminary clinical research in patients with chronic atrophic gastritis shows that taking lion's mane mushroom (unknown dose) before meals daily for 3 months improves upper abdominal pain in about 27% more patients, improves dyspepsia in about 39% more patients, and reduces inflammatory infiltration in about 23% more patients when compared with placebo (92630).
• Hyperlipidemia. Although there is interest in using oral lion's mane mushroom for hyperlipidemia, there is insufficient reliable information about the clinical effects of lion's mane mushroom for this condition.
• Memory. Although there is interest in using oral lion's mane mushroom for memory, there is insufficient reliable information about the clinical effects of lion's mane mushroom for this purpose.
• Multiple sclerosis (MS). Although there is interest in using oral lion's mane mushroom for MS, there is insufficient reliable information about the clinical effects of lion's mane mushroom for this condition.
• Obesity. Although there is interest in using oral lion's mane mushroom for obesity, there is insufficient reliable information about the clinical effects of lion's mane mushroom for this condition.
• Parkinson disease. Although there is interest in using oral lion's mane mushroom for Parkinson disease, there is insufficient reliable information about the clinical effects of lion's mane mushroom for this condition.
• Peptic ulcers. Although there is interest in using oral lion's mane mushroom for peptic ulcers, there is insufficient reliable information about the clinical effects of lion's mane mushroom for this condition.
• Wound healing. Although there is interest in using topical lion's mane mushroom for wound healing, there is insufficient reliable information about the clinical effects of lion's mane mushroom for this condition. More evidence is needed to rate lion's mane mushroom for these uses.

(Read more about LION'S MANE MUSHROOM)

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Dental caries. It is unclear if topical nutmeg is beneficial in children with dental caries. Details: A small clinical study in children aged 6-9 years shows that use of a nutmeg 2% extract gel as pulpotomy for a primary molar is as effective as formocresol for preventing pain, swelling, and root problems for 12 months (103371).
• Diarrhea. Although there has been interest in using oral nutmeg for diarrhea, there is insufficient reliable information about the clinical effects of nutmeg for this purpose.
• Halitosis. It is unclear if nutmeg is beneficial for halitosis. Details: A small clinical study in patients in India with plaque and plaque-induced halitosis shows that rinsing with 10 mL of a mouthwash containing nutmeg 2%, olive oil, menthol, orange oil, and other ingredients twice daily for 3 weeks reduces plaque and halitosis scores when compared to baseline, but not when compared with chlorhexidine gluconate 0.2% (111749). More evidence is needed to rate nutmeg for these uses.

(Read more about NUTMEG)

EFFECTIVE

• Hypokalemia. Oral or intravenous potassium can treat and prevent hypokalemia. Details: Administering potassium orally or intravenously is effective for treating and preventing hypokalemia (15,107970). Oral potassium 20 mEq (780 mg of elemental potassium) is typically taken once daily to prevent hypokalemia (15,95010). Oral potassium 40-100 mEq (1560-3900 mg of elemental potassium) is typically taken in 2-5 divided doses daily to treat hypokalemia (95010). Doses should be limited to 40 mEq (1560 mg of elemental potassium), and the total dose should not exceed 200 mEq (7800 mg of elemental potassium) in 24 hours (95010). Potassium supplementation and route of administration should be individualized based on serum potassium level and patient status (15,107970).

LIKELY EFFECTIVE

• Hypertension. Oral potassium, via dietary intake or supplementation, reduces blood pressure. Details: Population research has found that higher dietary potassium consumption is associated with a lower risk of developing hypertension (1310,8817,69512). Additionally, most clinical research shows that potassium, taken orally as part of the diet or as a supplement, reduces systolic blood pressure by about 3-9.5 mmHg and diastolic blood pressure by about 2-6.4 mmHg in patients with or without hypertension (3385,92104,92106,95624,107974). In most of these studies, daily intake of potassium typically ranged from about 1500-7800 mg, with the most common intake being about 2340-2540 mg daily (92104,95624). However, some research shows that taking potassium does not lower systolic or diastolic blood pressure (69541,69550,107966). Differences in the patient populations, potassium intake, and salt intake could have contributed to the conflicting results. Potassium seems to be more effective for people with hypertension, low potassium levels, high daily sodium intake, and for Black adults (3384,3385,3386,92104,92106). Some research also shows that the greatest blood pressure-lowering effects of potassium occur at doses of about 3900-7800 mg daily (95624). A meta-analysis of clinical trials using a novel computational technique to assess both potassium intake and excretion suggests that the optimal blood pressure reduction occurs when taking about 1500 mg supplemental potassium daily or an overall intake of 4500-6500 mg potassium daily (105448). This analysis is limited by the heterogeneity and short duration of the included trials. There is also interest in utilizing low-sodium, high-potassium food substitutes to treat hypertension. Research shows that using salt substitutes containing 25% to 30% potassium chloride reduces systolic and diastolic blood pressure by 3-4.6 mmHg and 1 mmHg, respectively, when compared with regular table salt (107971,107976). In 2017, the American College of Cardiology and the American Heart Association (ACC/AHA) published guidelines recommending that patients with hypertension consume 3500-5000 mg of potassium daily (95680). This intake of potassium is expected to lower systolic blood pressure by about 4-5 mmHg in patients with hypertension and by about 2 mmHg in normotensive patients (3385). Although potassium supplements and dietary potassium both seem to be beneficial, the guidelines recommend getting potassium from dietary sources, since potassium-rich diets are usually heart-healthy (95680). Additionally, the US Food and Drug Administration (FDA) has determined that foods containing at least 350 mg potassium and that are low in sodium, saturated fat, and cholesterol can state that "diets containing foods that are good sources of potassium and low in sodium may reduce the risk of high blood pressure and stroke" (1310,8817).
• Kidney stones (nephrolithiasis). Oral prescription potassium citrate reduces the risk of kidney stone recurrence. It is unclear if non-prescription potassium citrate would be beneficial. Details: The American Urological Association (AUA) recommends potassium citrate therapy for patients with recurrent calcium stones and low urinary citrate, those with recurrent calcium or calcium oxalate stones without current metabolic abnormalities, and those with uric acid or cystine stones. The citrate component reduces urine calcium excretion and increases urine citrate and urine pH, which in turn alleviates crystal growth, formation, and aggregation. Sodium citrate may also be used to prevent stone recurrence; however, due to sodium's propensity to increase urine calcium excretion, potassium citrate remains the preferred salt formulation (107972). It is important to note that potassium citrate supplements are not equivalent to prescription potassium citrate products. Dose and duration of treatment is determined by a healthcare professional and individualized based on a patient's urinary citrate levels (107975,107989). Serum potassium levels should be monitored prior to starting potassium citrate, within 2 weeks of treatment initiation, and every 12 months (107975).

POSSIBLY EFFECTIVE

• Cardiovascular disease (CVD). Eating foods high in potassium and low in sodium might reduce the risk of cardiovascular disease. It is unclear if taking potassium supplements has the same benefit. Details: Large population studies in adults without prior CVD have found that higher dietary potassium intake is associated with a lower risk of cardiovascular events (109395,109399). One study found that daily potassium intake of about 3300 mg is associated with a 13% reduction in CVD risk when compared with intake of about 1920 mg (109399). The other study found that each additional 1000 mg of daily urinary potassium excretion, which is a marker of dietary intake, is associated with an 18% reduction in CVD risk (109395). Another observational study in over 15,000 adults with history of stroke or hypertension shows that replacing regular table salt with a substitute product containing 75% sodium chloride and 25% potassium chloride for an average of 5 years decreases the rate of stroke, major cardiovascular events, or death (107976). High quality clinical trials are needed to confirm this association. The US Food and Drug Administration (FDA) has determined that foods containing at least 350 mg potassium and that are low in sodium, saturated fat, and cholesterol can state that "diets containing foods that are good sources of potassium and low in sodium may reduce the risk of high blood pressure and stroke" (1310,8817).
• Stroke. Eating foods high in potassium and low in sodium might reduce the risk of stroke. It is unclear if taking potassium supplements has the same benefit. Details: Higher dietary intake of potassium seems to be associated with a lower risk of stroke. Population research has found that increasing dietary potassium intake by 1-1.5 grams daily is associated with up to a 20% reduced risk of stroke (92105,92107). Some population research has found that higher supplemental intake of potassium is associated with a 29% reduced risk of ischemic stroke. However, supplemental potassium intake is not found to be associated with a lower risk of hemorrhagic or total stroke (92107). An observational study in over 15,000 adults with history of stroke or hypertension shows that replacing regular table salt with a substitute product containing 75% sodium chloride and 25% potassium chloride for an average of 5 years decreases the rate of stroke, major cardiovascular events, or death (107976). High quality clinical trials are needed to confirm this association. The US Food and Drug Administration (FDA) has determined that foods containing at least 350 mg potassium and that are low in sodium, saturated fat, and cholesterol can state that "diets containing foods that are good sources of potassium and low in sodium may reduce the risk of high blood pressure and stroke" (1310,8817).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Dental hypersensitivity. It is unclear if topical potassium improves dental hypersensitivity. Details: One meta-analysis of clinical research shows that using a dentifrice containing 5% potassium nitrite reduces dentin sensitivity when compared with a dentifrice that does not contain potassium nitrite (69549). Other clinical research published in a systematic review shows that potassium-containing toothpastes might reduce dentin sensitivity more than controls that do not contain potassium. However, these toothpastes might be less effective than other active toothpastes, such as those containing sodium monofluorophosphate, and the effect may result from a placebo effect, since the mechanism of action of potassium is unclear (69456).
• Diabetes. It is unclear if increasing dietary potassium reduces the risk of diabetes. Details: A meta-analysis of 7 large population studies has found that consuming dietary potassium 3300-3500 mg daily is associated with a 20% reduction in the risk of diabetes when compared with consumption below 1000 mg daily. Results were similar when studies that measured potassium intake with a dietary questionnaire were analyzed separately from those that measured intake based on urinary potassium excretion (110776). However, the validity of this finding is limited by the heterogeneity of the included studies. Furthermore, despite use of data from various databases, most studies included in the analysis were conducted by the same author.
• Impaired glucose tolerance (prediabetes). It is unclear if oral potassium improves glycemic control in prediabetes. Details: A small clinical study in Black patients with prediabetes shows that taking extended-release potassium (Klor-Con M10, Cardinal Health) 40 mEq daily as potassium chloride for 3 months does not improve glucose tolerance when compared with placebo. Although fasting glucose levels were slightly reduced in the potassium group when compared with placebo, both groups experienced a worsening of glucose intolerance, with no change in insulin levels or glycated hemoglobin (98533).
• Osteoporosis. Although there is interest in using oral potassium for osteoporosis, there is insufficient reliable information about the clinical effects of potassium for this condition.
• Physical performance. It is unclear if oral potassium improves physical performance in older adults. Details: Observational research in older adults has found that decreased dietary potassium intake and increased dietary sodium intake over 5 years is associated with worsened physical performance (105450).
• Systemic lupus erythematosus (SLE). It is unclear if oral potassium is beneficial in patients with SLE. Details: Observational research in patients with SLE has found that increased dietary potassium intake is not associated with improvements in disease activity scores or markers of cardiovascular disease, including lipid levels and blood pressure, when compared with low dietary potassium intake. However, higher potassium intake does seem to reduce the odds of having elevated levels of C-reactive protein, a marker of inflammation, in these patients (109397). More evidence is needed to rate potassium for these uses.

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POSSIBLY INEFFECTIVE

• Hyperlipidemia. Preliminary clinical studies show that oral reishi mushroom does not improve lipid levels in patients with hyperlipidemia or type 2 diabetes. Details: Preliminary clinical research shows that taking reishi mushroom extract 1440 mg daily for 12 weeks does not significantly improve the lipid profile in patients with hyperlipidemia (70776). Also, a meta-analysis shows that taking reishi mushroom extract 1400-4000 mg daily for 12-16 weeks does not reduce total cholesterol or low-density lipoprotein (LDL) cholesterol in patients with type 2 diabetes (91435).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Aging. Although there has been interest in using oral reishi mushroom for aging, there is insufficient reliable information about the clinical effects of reishi mushroom for this purpose.
• Altitude sickness. Although there has been interest in using oral reishi mushroom for altitude sickness, there is insufficient reliable information about the clinical effects of reishi mushroom for this purpose.
• Alzheimer disease. A small clinical study suggests that oral reishi mushroom does not improve Alzheimer disease symptoms. Details: Preliminary clinical research in patients with Alzheimer disease shows that taking reishi mushroom powder 1000 mg three times daily for 6 weeks does not improve memory, language skills, or quality of life when compared with placebo (97942).
• Asthma. Although there has been interest in using oral reishi mushroom for asthma, there is insufficient reliable information about the clinical effects of reishi mushroom for this purpose.
• Benign prostatic hyperplasia (BPH). Preliminary clinical research suggests that oral reishi mushroom extract can help reduce some lower urinary tract symptoms in patients with BPH. Details: Clinical research in patients with mild to moderate lower urinary tract symptoms (LUTS) associated with BPH, urinary incontinence, overactive bladder, or other conditions, shows that taking reishi mushroom extract 6 mg orally once daily for up to 12 weeks moderately improves total symptom severity measured on the International Prostate Symptom Score (IPSS) scale, when compared with placebo (91436,91437). A higher dose of 60 mg daily is not more effective than the 6 mg dose, and a lower dose of 0.6 mg daily is not more effective than placebo (91437). Reishi mushroom extract does not improve peak urine flow rate, residual urine volume, prostate volume, or quality of life when compared with placebo (91436,91437). The relevance of these results is unclear since not all of the patients with LUTS had BPH.
• Bronchitis. Although there has been interest in using oral reishi mushroom for bronchitis, there is insufficient reliable information about the clinical effects of reishi mushroom for this purpose.
• Cancer. It is unclear if oral reishi mushroom is beneficial when used in conjunction with chemotherapy. Details: A meta-analysis of 9 clinical trials using various reishi mushroom products in combination with chemotherapy found that complete and partial responses increased by 30% with combination therapy when compared with chemotherapy alone. However, there was no difference in overall survival (102915). The reliability and applicability of these results are unclear since the trials looked at several different types of cancer, used varying doses and durations of therapy, and were all conducted in China or other Asian countries.
• Cancer-related fatigue. It is unclear if oral reishi mushroom is beneficial in patients with breast cancer and fatigue. Details: Results from a small clinical study in breast cancer patients show that taking reishi mushroom powder 1000 mg orally three times daily for 4 weeks can improve cancer-related fatigue when compared with placebo (91438). However, it is not clear if the improvement is clinically meaningful.
• Cardiovascular disease (CVD). It is unclear if oral reishi mushroom is beneficial for reducing CVD risk factors. Details: A meta-analysis of 5 low-quality studies in adults with diabetes shows that taking reishi mushroom 1400-3000 mg daily for 12-16 weeks does not reduce CVD risk factors, including total and low-density lipoprotein (LDL) cholesterol, triglycerides, blood pressure, and body mass index, when compared with placebo (91435).
• Chronic fatigue syndrome (CFS). Although there has been interest in using oral reishi mushroom for CFS, there is insufficient reliable information about the clinical effects of reishi mushroom for this purpose.
• Chronic kidney disease (CKD). Although there has been interest in using oral reishi mushroom for CKD, there is insufficient reliable information about the clinical effects of reishi mushroom for this purpose.
• Colorectal adenoma. Limited clinical research suggests that oral reishi mushroom extract may be beneficial for reducing colorectal adenoma size. Details: Preliminary clinical research in patients with colorectal adenomas shows that taking reishi mushroom extract 1500 mg orally in two divided doses daily for 12 months reduces the number and size of adenomas when compared with no treatment (70774).
• Coronary heart disease (CHD). It is unclear if oral reishi mushroom is beneficial for CHD. Details: Preliminary clinical research shows that taking a specific reishi mushroom extract (Ganopoly, Encore International Co.) 1800 mg orally three times daily for 12 weeks reduces symptoms of CHD, such as chest pain, palpitations, and shortness of breath, in a greater percentage of patients when compared with placebo (70800).
• Diabetes. Evidence on the use of oral reishi mushroom in patients with type 2 diabetes is conflicting. Details: A meta-analysis of clinical research in patients with type 2 diabetes shows that taking reishi mushroom extract 1400-4000 mg daily for 12-16 weeks does not reduce glycated hemoglobin (HbA1c) or plasma lipids (91435). However, one preliminary clinical study in patients with type 2 diabetes shows that taking a specific reishi mushroom extract (Ganopoly, Encore International Co.) 1800 mg three times daily for 12 weeks reduces HbA1c, but not fasting blood glucose, when compared with placebo (70801).
• Fibromyalgia. It is unclear if oral reishi mushroom is beneficial for fibromyalgia. Details: A small clinical trial in patients with fibromyalgia shows that taking reishi mushroom (MundoReishi Salud S.L.) powder 3 grams twice daily for 6 weeks does not improve mood, quality of life, anthropometric measures, blood pressure, or glycemic or lipid parameters when compared with placebo (108309,108310). However, the study may have been underpowered to detect any differences between groups.
• Genital herpes. Oral reishi mushroom has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research in adults with recurrent genital herpes shows that taking 4.4 grams of a mixture of hot water extracts of reishi mushroom, terminalia, Job's tears, Wisteria floribunda, Trapa natans, and Elfvingia applanata orally once daily for 2 days, then 2.2 grams daily thereafter until outbreak resolution, decreases the time to outbreak resolution by 6 days when compared with previous outbreaks (91434).
• Gulf war syndrome. It is unclear if oral reishi mushroom is beneficial for Gulf war syndrome. Details: A very small exploratory clinical trial in adults with Gulf war syndrome shows that taking reishi mushroom extract (JHS Natural Products, Mushroom Science) 1600 mg in two divided doses daily for 30 days does not improve symptoms when compared with placebo. Also, symptoms modestly worsened after an additional 30 days of treatment at a dose of 3200 mg daily (108311).
• Hepatitis B. One small clinical study suggests that a specific reishi mushroom extract may reduce hepatitis B activity and improve liver function. Details: Preliminary clinical research shows that taking a specific reishi mushroom extract (Ganopoly, Encore International Co.) 1800 mg orally three times daily for 12 weeks reduces levels of hepatitis B viral DNA and hepatitis B surface antigen, which are markers of hepatitis B activity, and normalizes aminotransferase levels in a greater percentage of patients when compared with placebo (70799).
• Herpes labialis (cold sores). Oral reishi mushroom has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research in adults with recurrent herpes labialis shows that taking 4.4 grams of a mixture of hot water extracts of reishi mushroom, terminalia, Job's tears, Wisteria floribunda, Trapa natans, and Elfvingia applanata orally once daily for 2 days, then 2.2 grams daily thereafter until outbreak resolution, decreases the time to outbreak resolution by almost 4 days when compared with previous outbreaks (91434).
• Herpes zoster (shingles). Although there has been interest in using oral reishi mushroom for herpes zoster, there is insufficient reliable information about the clinical effects of reishi mushroom for this purpose.
• Human papillomavirus (HPV). Oral reishi mushroom has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research in patients with oral HPV shows that taking a combination of reishi and coriolus mushroom powders, 400 mg orally daily for 2 months, clears HPV in 88% of patients when compared with baseline (91433). The validity of this finding is limited by the lack of a comparator group.
• Hypertension. Limited research suggests that oral reishi mushroom may be beneficial in some types of hypertension. Details: Preliminary clinical research shows that taking reishi mushroom extract 1440 mg daily for 12 weeks does not lower blood pressure in patients with hypertension (70776). However, in other clinical research, taking reishi mushroom extract 330-1440 mg daily for 1-6 months reduces blood pressure in patients with stage II or essential hypertension, but not in those with mild hypertension or diabetes (70786,70802,91435).
• Influenza. Although there has been interest in using reishi mushroom for influenza, there is insufficient reliable information about the clinical effects of reishi mushroom for this purpose.
• Insomnia. Although there has been interest in using reishi mushroom for insomnia, there is insufficient reliable information about the clinical effects of reishi mushroom for this purpose.
• Lung cancer. Small clinical studies suggest that oral reishi mushroom does not reduce the size of lung tumors. Details: A meta-analysis of preliminary clinical research shows that taking reishi mushroom does not reduce the size of lung tumors. However, it may stimulate immune function and improve quality of life in lung cancer patients when compared with control (70779).
• Peptic ulcers. Although there has been interest in using oral reishi mushroom for peptic ulcers, there is insufficient reliable information about the clinical effects of reishi mushroom for this purpose.
• Rheumatoid arthritis (RA). Oral reishi mushroom has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical trial in patients with active RA who are taking disease-modifying antirheumatic drugs shows that taking reishi mushroom extract 4 grams in combination with San Miao San (containing 2.4 grams each of atractylodes, phellodendron, and Achyranthes bidentata) daily for 24 weeks does not increase the percentage of patients achieving a 20% response based on the American College of Rheumatology (ACR) criteria or modify blood markers of disease and inflammation when compared with placebo (70767).
• Stress. Although there has been interest in using oral reishi mushroom for stress, there is insufficient reliable information about the clinical effects of reishi mushroom for this purpose. More evidence is needed to rate reishi mushroom for these uses.

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LIKELY EFFECTIVE

• Cystic fibrosis. Long-term nebulized hypertonic sodium chloride improves lung function and reduces pulmonary exacerbations in patients with cystic fibrosis. Details: Meta-analyses of clinical research in adults with cystic fibrosis show that, when taken along with a bronchodilator and other standard therapies, nebulized hypertonic sodium chloride in concentrations of 3% to 7%, up to 10 mL twice daily for 4 weeks, increases forced expiratory volume at one second (FEV1) when compared with isotonic saline (sodium chloride 0.9%) (26230,26230). This benefit was not seen at 48 weeks. Other clinical research in adults with cystic fibrosis shows that inhaling sodium chloride 7%, 4 mL twice daily for 48 weeks, does not improve FEV1 when compared with isotonic saline. However, chronic treatment with hypertonic saline does reduce the number of pulmonary exacerbations and increase the number of patients without pulmonary exacerbations when compared with isotonic saline (29402). It is not clear if this benefit occurs in children with cystic fibrosis. The Pulmonary Clinical Practice Guidelines Committee of the Cystic Fibrosis Foundation recommends that individuals with cystic fibrosis aged 6 years or older use nebulized hypertonic saline long-term to improve lung function, reduce the number of exacerbations, and improve quality of life (29403).

POSSIBLY EFFECTIVE

• Amphotericin B nephrotoxicity. Oral sodium chloride seems to prevent nephrotoxicity associated with use of amphotericin B. Details: Clinical research shows that administering oral or intravenous sodium chloride 150 mEq daily during treatment with amphotericin B can attenuate the rise in serum creatinine levels and preserve renal function when compared to treatment with amphotericin B alone (26226).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Bipolar disorder. It is unclear if oral sodium is beneficial in preventing lithium level fluctuations in patients with bipolar disorder. Details: A moderate-sized open-label clinical study in adults with type I bipolar disorder receiving lithium carbonate shows that taking sodium chloride 1 gram daily for 12 weeks along with dietary salt restriction of 1 gram daily reduces the percentage of patients with lithium level fluctuations above 0.8 mEq/L, but does not significantly affect serum sodium, potassium, aldosterone, or creatinine levels when compared with controls who were not salt restricted, but were advised not to consume additional salt at the table (112909). However, the interpretation of these findings is limited by missing data in both groups.
• Canker sores. Although there is interest in using topical sodium chloride for canker sores, there is insufficient reliable information about the clinical effects of sodium chloride for this condition.
• Congestive heart failure. It is unclear if oral sodium is beneficial in patients with acute decompensated heart failure requiring decongestive therapy with diuretics. Details: A moderate-sized clinical study in adults hospitalized with acute decompensated heart failure requiring high-dose intravenous furosemide shows that taking sodium chloride 2 grams three times daily for up to 96 hours does not affect patient weight or serum creatinine levels when compared with placebo (112911). However, the clinical relevance of this study is unclear and it may have been inadequately powered to detect a difference between groups.
• Conjunctivitis. Although there is interest in using ophthalmic sodium chloride for conjunctivitis, there is insufficient reliable information about the clinical effects of sodium chloride for this condition.
• Hyponatremia. Although there is interest in using oral sodium chloride for hyponatremia, there is insufficient reliable information about the clinical effects of oral sodium chloride for this condition.
• Pharyngitis. Although there is interest in using topical sodium chloride for pharyngitis, there is insufficient reliable information about the clinical effects of sodium chloride for this condition.
• Prematurity. It is unclear if oral sodium is beneficial for premature infants. Details: Preliminary clinical research in infants born at less than 32 weeks' gestation shows that adding sodium 4 mEq/kg daily to enteral feedings, starting from the 7th day after birth and continuing through the 35th day, reduces the risk of developing hyponatremia and improves weight gain when compared with adding water (98180). A small, open-label clinical study in newborns less than 35 weeks gestation shows that high sodium intake, defined as an average of 0.25% sodium in maintenance fluids, for 48 hours on day 2 and 3 after birth results in less weight loss within the first 72 hours of life when compared with control, but does not improve mortality, length of hospital stay, or complications from prematurity (112908). However, interpretation of these findings is limited by varied concentrations of sodium as an intervention. More evidence is needed to rate sodium for these uses.

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POSSIBLY EFFECTIVE

• Allergic rhinitis (hay fever). Oral turmeric seems to improve symptoms in people with allergic rhinitis. Details: A large clinical study in people with allergic rhinitis shows that taking a specific curcumin product (Organika Health Products) 500 mg daily for 2 months reduces nasal symptoms, including sneezing, itching, runny nose, and congestion, when compared with placebo (96138).
• Depression. Most research shows that oral curcumin, a constituent of turmeric, 1 gram daily improves symptoms of depression after 6 weeks when taken along with an antidepressant. However, it is unclear whether curcumin is beneficial when used for greater than 8 weeks. Details: Curcumin appears to be most beneficial for depression in middle aged patients compared to older patients, when taken for at least 6 weeks, and when used at a dose of at least 1 gram daily. In adults with major depressive disorder, a meta-analysis of data from six clinical studies, as well as individual studies not included in this analysis, show that taking curcumin 1 gram daily along with an antidepressant moderately improves depression symptoms when compared with placebo (96131,96139). Another meta-analysis of 10 studies shows symptom reductions in patients with major depression when combined with conventional antidepressants, but not when used alone in patients with milder depressive symptoms. However, the quality of the evidence is low (104971). When used alone, one clinical study shows that curcumin 1 gram daily for 6 weeks may be similarly effective to fluoxetine 20 mg daily. Taking both products together seems to be more effective than either product alone, increasing the response rate from 65% to 78% (89728). Guidelines from The World Federation of Societies of Biological Psychiatry (WFSBP) and Canadian Network for Mood and Anxiety Treatments (CANMAT) Taskforce state that curcumin extract at doses of 500-1000 mg daily is provisionally recommended for monotherapy or adjunctive use in mild to moderate depression (110318).
• Dyspepsia. Oral turmeric may be modestly beneficial for some patients with dyspepsia. In patients with functional dyspepsia, small clinical studies show that oral curcumin, a constituent of turmeric, is similarly effective when compared with the proton-pump inhibitor omeprazole. Details: Clinical research shows that taking turmeric 500 mg four times daily for 7 days can relieve overall symptoms of dyspepsia in 64% more patients than taking placebo (11144). A small, unblinded clinical study in patients with a type of dyspepsia called postprandial distress syndrome shows that taking turmeric 250 mg or 500 mg orally three times daily after meals for 4 weeks is associated with reductions in symptom scores which are similar to those seen with simethicone 60 mg three times daily for 4 weeks. However, the recurrence rate upon stopping therapy was about 14% with simethicone, compared with 43% to 46% with turmeric (104963). In patients with functional dyspepsia, taking the constituent curcumin appears similarly effective when compared with omeprazole, but might not provide further symptom reduction in those also taking famotidine or omeprazole (106063,106801,111599). One small clinical study in Iran shows that taking curcuminoids (C3 Complex, Sami Labs) 500 mg with piperine (Bioperine) 5 mg daily in addition to famotidine 40 mg daily for 30 days is no more effective for reducing overall symptoms of dyspepsia, such as abdominal pain, heartburn, bloating, and nausea, when compared with famotidine alone (106063). Another small clinical study in Thailand shows that taking curcumin 500 mg four times daily for 4 weeks is similarly effective for reducing dyspepsia severity and improving satisfaction when compared with an unspecified dose of omeprazole and more effective when compared with placebo (106801). Similarly, a moderate-size clinical study in Thailand shows that taking curcumin 500 mg four times daily for 4 weeks is similarly effective for reducing dyspepsia severity when compared with omeprazole 20 mg daily. However, taking curcumin and omeprazole in combination did not provide further symptom reduction (111599). The validity of these results is limited by the high rate of study dropouts.
• Hyperlipidemia. Research is conflicting on whether oral turmeric, curcumin, or curcuminoids can reduce serum lipids. Any improvement in lipids is likely to be small. Reasons for the conflicting findings may relate to turmeric formulation, duration of treatment, and/or the baseline cholesterol status of the included patients. Details: Results from meta-analyses of clinical research show inconsistent and conflicting results. One large meta-analysis of over 50 clinical studies in healthy adults and those with a variety of conditions shows that supplementation with turmeric or curcumin 80-4000 mg daily for 4-24 weeks reduces total cholesterol by 4 mg/dL, low-density lipoprotein (LDL) cholesterol by 5 mg/dL, and triglycerides by 7 mg/dL and increases high-density lipoprotein (HDL) cholesterol by 2 mg/dL when compared with placebo (112119). Two other meta-analyses of 27 clinical studies agree that taking turmeric, curcumin, or curcuminoids moderately reduce triglyceride levels but suggest that turmeric does not improve total cholesterol when compared with placebo. However, the meta-analyses contradict one another on whether turmeric and its constituents reduce LDL cholesterol or increase HDL cholesterol. (96128,96135). Additionally, a third meta-analysis of 10 clinical trials shows that taking up to 2400 mg daily of curcumin or curcuminoids, from turmeric or isolated sources, for up to 12 weeks, does not significantly improve triglycerides, LDL cholesterol, HDL cholesterol, or total cholesterol (110220).
• Nonalcoholic fatty liver disease (NAFLD). Oral curcumin, a constituent of turmeric, seems to attenuate fat deposition and improve some metabolic parameters in adults with NAFLD. Details: Clinical research shows that taking curcumin daily reduces NAFLD severity in 30% to 79% of patients, compared to 5% to 27.5% of patients receiving placebo. Curcumin also reduces the quantity of additional fat deposition in the liver to 0% to 4.5%, compared to 17.5% to 26% in those taking placebo. Most research shows that taking curcumin also reduces liver enzyme levels, body mass index (BMI), blood glucose levels, glycated hemoglobin (HbA1c), and total cholesterol when compared with placebo. Although some clinical research shows that taking curcumin improves levels of low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and triglycerides, a meta-analysis of clinical research shows that these lipid levels are not improved in patients with NAFLD, specifically (97430,97431,100258,102350,106062,107120,109279,111349). However, another meta-analysis of 14 small, heterogeneous clinical studies in adults with NAFLD, that included some of these studies, shows that taking various doses and forms of turmeric or curcumin modestly reduces liver enzyme levels, improves measures of insulin resistance, reduces waist circumference, and improves LDL, HDL, and triglyceride levels when compared with placebo (111348). A small clinical trial in patients with NAFLD given specific lifestyle recommendations shows that taking curcumin modestly reduces the frequency of metabolic syndrome and fatty liver but does not have beneficial effects on fatty liver-associated indices, adiposity, or the atherogenic index, when compared with placebo (109285). Findings for specific endpoints are mixed between individual studies and may depend on the formulation of curcumin used or the duration of treatment. These studies have used various doses and formulations. In one study, 500 mg of a dispersion formulation equivalent to 70 mg of curcumin daily for 8 weeks was used (97430). Also, 250 mg once daily or 500 mg twice daily of a specific phytosomal formulation (Meriva, Indena) containing curcumin and soy phosphatidylcholine in a 1:2 ratio and standardized to an overall curcuminoid content of 20% was taken for 8 weeks (97431,106062). Another study used 1 gram of powdered turmeric rhizome taken three times daily with meals for 12 weeks (102350). One study used a curcumin-piperine complex (Curcumin C3 complex 500 mg plus Bioperine 5 mg) daily for 8 weeks (107120). One study used curcumin (Arjuna Natural Extract) 500 mg three times daily for 12 weeks (109285). Despite positive results with curcumin in several small clinical studies of patients with NAFLD, there is some concern that curcumin might cause hepatotoxicity in rare cases, especially when highly bioavailable formulations are used in high doses (103633). There is also evidence that the risk for hepatotoxicity with curcumin may be increased in individuals with the HLAB*35:01 allele (109288). Curcumin-induced hepatotoxicity has not been reported in clinical trials of patients with NAFLD, and its potential mechanism is unclear. However, patients seeking to take curcumin for NAFLD should be advised to monitor for symptoms of hepatotoxicity, including abdominal pain, dark urine, fatigue, jaundice, nausea, and pruritus.
• Oral mucositis. Oral curcumin or curcumin-containing mouthwash seem to reduce the development of severe oral mucositis, as well as reduce the severity and pain of oral mucositis, associated with cancer treatment. Details: Clinical research in patients receiving radiotherapy following recent radical surgery for oral cancer shows that taking turmeric (BCM-95, Arjuna Natural Pvt. Ltd., India) during radiotherapy reduces the incidence of severe oral mucositis to 25% or 20% in those taking turmeric 500 mg two or three times daily, respectively, compared with 65% in those taking placebo. The incidences of severe oral pain, dysphagia, and dermatitis were also reduced by at least 50% (105398). A small clinical study in patients receiving chemotherapy with or without head and neck radiotherapy shows that taking a specific nanoparticle formulation of curcumin (SinaCurcumin, ExirNanoSina) 80 mg twice daily for 7 weeks improves severity of oral mucositis at weeks 1, 4, and 7 and reduces pain at week 7 when compared with placebo. Effects were more pronounced in those with chemotherapy-induced oral mucositis than radiotherapy-induced oral mucositis (106800). In patients with head and neck cancer receiving radiotherapy, preliminary clinical research shows that swishing with 10 mL of turmeric solution (prepared by dissolving turmeric 400 mg in 80 mL of water) six times daily for 6 weeks delays mucositis and reduces the number of cases of intolerable mucositis by 49% when compared to swishing with 10 mL of povidone-iodine solution twice daily for 6 weeks (89726). Another small clinical study shows that swishing with 10 mL of nanoparticulate curcumin 0.1% mouthwash three times daily for 6 weeks is associated with a 50% lower risk of developing oral mucositis, and a delay of 2 weeks in the onset of mucositis, when compared with benzydamine 0.15% mouthwash (104969). A small clinical study in patients with mucositis due to head and neck radiotherapy shows that taking curcumin nanoparticles (SinaCurcumin, ExirNanoSina) 40 mg daily or using 10 mL of a curcumin 0.1% mouthwash three times daily for up to 21 days improves scores related to pain, burning, ulceration, and erythema when compared with placebo. Results with either oral or topical curcumin were similar (111350).
• Osteoarthritis. Some oral turmeric extracts and combination products containing turmeric seem to improve certain symptoms of knee osteoarthritis. However, it is unclear how turmeric compares to the use of non-steroidal anti-inflammatory drugs (NSAIDs). Details: Several meta-analyses of clinical studies show that turmeric extracts and/or curcuminoid products reduce knee pain and stiffness, improve physical function, and reduce the need for rescue medication when compared with placebo (104970,106792,109280,110222). However, a reduced effect was noted in patients with increasing age or body mass index (104790). The studies evaluated in these meta-analyses are heterogeneous, of low- to moderate-quality, and utilized a variety of products and/or dosing strategies (104970,106792,109280,110222). Small to moderate-sized clinical studies show that specific products (Meriva, Indena; Theracurmin, Theravalues Corp) containing curcumin 90-100 mg twice daily for up to 6 months, or specific turmeric extracts (Turmacin, Natural Remedies Pvt. Ltd.; Curcugen, DolCas Biotech, LLC) 500 mg twice daily for 6-12 weeks, reduce pain and analgesic use and improve functionality when compared with placebo (17953,80988,89721,97424,104148,107118). A specific turmeric extract (CuraMed, EuroPharma USA) 1500 mg daily for 12 weeks improves functionality, but not pain, when compared with placebo (96127). Also, a specific nanoparticle formulation of curcumin (SinaCurcumin, ExirNanoSina), 40 mg twice daily for 6 weeks, improves pain, stiffness, and physical activity scores and reduces intake of rescue acetaminophen by about 60% when compared with placebo (102349). However, not all turmeric products seem to be effective for improving symptoms of osteoarthritis. One small clinical study shows that taking a specific turmeric extract (B-Turmactive, PLAMECA S.A.) 500 mg daily for one week does not reduce knee pain when compared with placebo (104147). Also, a meta-analysis of clinical research shows that benefits are limited to bio-optimized forms of curcuminoids, and benefits related to pure extracts are lacking (110222). Turmeric has also been compared with conventional treatments for knee osteoarthritis in small meta-analyses, a network meta-analysis, and individual clinical studies. However, the evidence is mixed as to whether turmeric is as effective or more effective than NSAIDs, such as ibuprofen 400 mg taken 2-3 times daily, diclofenac 25-100 mg daily, or chondroprotective drugs (17952,89720,89722,106792,109280,110222,113607). A network meta-analysis comparing 6 interventions in adults with knee osteoarthritis suggests that curcumin monotherapy, curcumin with chondroprotective agents, or curcumin with NSAIDs improves scores related to pain, function, and stiffness while reducing the need for rescue medication and the incidence of adverse events (113607). Individual studies are heterogenous with respect to comparator medication and dosing schedule. Doses included a non-commercial turmeric extract 500 mg 3-4 times daily for 4-6 weeks (17952,89720) or turmeric extract 500 mg twice daily for 3 months (89722). Topical turmeric has also been evaluated. One clinical study shows that applying curcumin topically as a 5% ointment in Vaseline twice daily for 6 weeks reduces pain associated with knee osteoarthritis by a mean of about 11 on a 100-point visual analog scale when compared with placebo (104964). Another clinical study in patients with knee osteoarthritis shows that applying curcumin in a self-nano-emulsifying polyethylene glycol organogel 1.5 grams to the knee twice daily for 8 weeks reduces pain, stiffness, and difficulty with physical function scores by 72%, 62%, and 46%, respectively, when compared to baseline, with improvements superior to placebo for all outcomes (113357). Research also shows that taking specific combination products containing turmeric and other ingredients can improve pain and functionality in patients with osteoarthritis. These combination products have combined turmeric with chondroitin sulfate and glucosamine hydrochloride (CartiJoint Forte, Fidia Farmaceutici SpA); boswellic acid (Curamin, EuroPharma USA; Rhulief); Boswellia serrata (Rhulief); ashwagandha, Boswellia serrata, and zinc (Articulin-F, Eisen Pharmaceutical Co. Pvt. Ltd.); devil's claw and bromelain (AINAT, Laboratoire de Rhumatologie Appliquée); Boswellia serrata, guggul, and valerian (Phytoproflex, OPTM Healthcare); Boswellia serrata and terminalia (LI73014F2, Laila Nutraceuticals); ashwagandha, Boswellia serrata, and ginger (Artrex, Mendar); or extracts of ginger rhizome, devil's claw tuber, Boswellia serrata resin, and celery seed (Tregocel, Max Biocare) (19276,51950,81466,89717,89719,96127,97419,97421,97428,106078)(109280).
• Pruritus. Oral turmeric has been evaluated for the management of pruritus of various etiologies, with promising results. Details: Clinical research in patients with kidney failure shows that taking turmeric 500 mg orally three times daily for 8 weeks decreases symptoms of uremic pruritus by 1.9-fold when compared with placebo (89724). Also, a small clinical study in patients with sulfur mustard-induced chronic pruritus shows that taking a specific combination product (C3 Complex, Sami Labs LTD) containing curcumin 1 gram plus extract from black pepper or long pepper (Bioperine) daily for 4 weeks reduces pruritus severity and improves quality of life when compared with placebo (81120,81176).

POSSIBLY INEFFECTIVE

• Alzheimer disease. Neither oral turmeric nor its constituent curcumin appears to improve cognitive function or attenuate cognitive decline in adults with this condition. Details: A small clinical trial shows that taking the turmeric constituent, curcumin, 1-4 grams daily for 6 months does not improve mental state examination scores when compared with placebo (17096). Furthermore, a meta-analysis of this study and another small clinical study in patients with Alzheimer disease shows that the turmeric group experienced greater cognitive decline when compared with placebo (100261). While this research is limited by small study sizes and heterogeneous patient populations, the current evidence does not support the use of turmeric in patients with this condition.
• Peptic ulcers. Oral turmeric does not seem to improve the healing of peptic or gastric ulcers when compared with placebo or liquid antacids. Details: Some clinical research shows that taking turmeric 2 grams three times daily for 8 weeks does not improve the healing of peptic ulcers when compared with placebo in Vietnamese patients (81444). Also, taking powdered turmeric rhizome 250 mg four times daily for 6 weeks seems to be less effective than a liquid aluminum-magnesium-hydroxide antacid for promoting gastric ulcer healing (81284).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Acne. Although there has been interest in using topical turmeric for acne, there is insufficient reliable information about the clinical effects of turmeric for this purpose.
• Age-related cognitive decline. Some small clinical studies suggest that oral curcumin, a constituent of turmeric, may modestly improve cognition in elderly patients experiencing cognitive decline. Details: A meta-analysis of three small clinical trials shows that curcumin modestly improves cognition in the elderly (100261). One of these clinical trials shows that taking a specific brand of curcumin (Theracurmin, Theravalues Corp.) 90 mg twice daily for 18 months improves long-term memory and attention when compared with placebo in middle-aged and older adults with or without mild cognitive impairment (96161).
• Amenorrhea. Although there has been interest in using oral turmeric for amenorrhea, there is insufficient reliable information about the clinical effects of turmeric for this purpose.
• Ankylosing spondylitis. Although there has been interest in using oral turmeric for ankylosing spondylitis, there is insufficient reliable information about the clinical effects of turmeric for this purpose.
• Aromatase inhibitor-induced arthralgia. It is unclear if oral curcumin, a constituent of turmeric, is beneficial for aromatase inhibitor-induced arthralgia. Details: A small clinical trial in patients experiencing aromatase inhibitor-induced arthralgia shows that taking curcuminoids as a nanoemulsion (Curcumin C3 Complex, Sabinsa Corporation) 200 mg daily for 3 months does not improve grip strength or joint symptoms when compared with placebo (113345). However, this study may have been underpowered to detect a difference between groups.
• Asthma. Some small clinical studies suggest that oral turmeric, as an adjunct to conventional asthma treatment, does not improve lung function or symptoms in adults and children with asthma. Details: One small clinical study in adults with mild to moderate asthma shows that adjuvant therapy with turmeric as curcumin 500 mg twice daily for 30 days does not improve lung function based on FEV1, or improve symptoms such as dyspnea, wheezing, cough, or tightness, when compared to standard treatment alone (99349). A small clinical trial in children 7-18 years of age with moderate to severe asthma shows that adding turmeric 500-1000 mg (containing 20-40 mg curcuminoids) daily for 6 months to standard therapy does not improve overall asthma symptoms when compared with placebo and standard therapy, although it may decrease the frequency of nighttime awakenings and the use of rescue inhalers (99348). Due to their small sizes and high drop-out rates, these studies may have been underpowered to detect a difference between groups.
• Athletic performance. It is unclear if oral curcumin, a constituent of turmeric, is beneficial for athletic performance. Details: Preliminary clinical research in middle-aged male long-distance runners shows that taking a turmeric extract providing 2 grams of curcumin 95% and piperine 5% daily for 6 weeks does not improve aerobic capacity when compared with placebo (109286).
• Benign prostatic hyperplasia (BPH). It is unclear if oral curcumin, a constituent of turmeric, is beneficial in BPH. Details: A clinical study in patients with BPH shows that taking curcumin 2250 mg once daily along with tamsulosin and finasteride for 6 months improves lower urinary tract symptoms related to storage, but not overall symptoms or symptoms related to voiding, by about 35%, compared with 25% in those receiving tamsulosin and finasteride alone. Periprostatic fat thickness, quality of life, and erectile function also were improved (106799).
• Beta-thalassemia. It is unclear if oral turmeric is beneficial for iron overload in patients with beta-thalassemia. Details: A small clinical study in patients with beta-thalassemia major and iron overload shows that taking turmeric extract containing curcumin 500 mg twice daily for 12 weeks modestly reduces non-transferrin bound iron (NTBI) by 0.6 micromol/L, but not hemoglobin, transferrin saturation, total iron binding capacity, ferritin, or hepcidin, when compared with placebo (99306). Another small clinical study in adult males with beta-thalassemia intermedia and iron overload shows that taking a higher dose of curcumin 500 mg three times daily for 12 weeks modestly reduces serum iron and ferritin turmeric levels and transferrin saturation when compared with placebo (108871).
• Bruises. Although there has been interest in using topical turmeric to alleviate bruising, there is insufficient reliable information about the clinical effects of turmeric for this purpose.
• Cachexia. It is unclear if oral curcumin, a constituent of turmeric, is beneficial for cancer cachexia. Details: A small clinical trial in patients with cancer anorexia-cachexia syndrome shows that taking curcumin 800 mg twice daily for 8 weeks does not reduce weight loss or improve body composition or handgrip strength when compared with placebo (109283).
• Canker sores. Some preliminary research suggests that topical curcumin, a constituent of turmeric, is beneficial for minor canker sores. Details: Preliminary clinical research in young adults with minor canker sores shows that applying a 2% curcumin oral gel for 6 months reduces ulcer size, pain, and recurrence rate and increases healing rate similarly to 0.1% triamcinolone oral paste (104962). The validity of the study is limited by a lack of investigator blinding and the lack of an intention to treat analysis. Another small clinical study shows that applying a 1% curcumin nanomicelle gel (SinaCurcumin Pharmaceuticals) on lesions three times daily for one week is modestly more effective than applying a 2% curcumin gel for reducing pain and ulcer size (109282). The validity of this finding is limited by the lack of a non-curcumin comparator group.
• Carpal tunnel syndrome. Oral turmeric has only been evaluated in combination with other ingredients; its effect when used alone is unclear. It is unclear if topical curcumin, a constituent of turmeric, is beneficial for carpal tunnel syndrome. Details: A moderate-sized clinical study in adults with mild to moderate carpal tunnel syndrome shows that taking a combination product containing turmeric, alpha-lipoic acid, acetyl-L-carnitine, phosphatidylserine, and vitamins C, E, B1, B2, B6, and B12 twice daily for 60 days reduces symptom severity and pain but does not improve measures of hand and wrist function when compared with control (111702). The validity of these effects is limited by a lack of blinding. The study may also be inadequately powered to detect a difference between groups. Additionally, it is unclear if the effects are due to turmeric, other ingredients, or the combination. Topical turmeric has also been investigated. A small clinical study in patients with mild to moderate carpal tunnel syndrome shows that applying a 1% curcuminoid gel (Sinanomin) to the wrists twice daily for 8 weeks modestly decreases symptom severity and improves function when compared with a placebo gel. However, there was no change in electrodiagnostic testing of the injury. All patients also used a night splint (113356).
• Chemotherapy-induced acral erythema. It is unclear if oral or topical turmeric reduces the risk for acral erythema from capecitabine. Details: A small clinical trial in adults with cancer shows that taking turmeric 4 grams daily for 6 weeks starting at the beginning of treatment with capecitabine does not reduce the incidence of acral erythema overall; however, it does seem to reduce acral erythema grade 2 or higher when compared with expected incidence rates (99309). Topical turmeric has also been evaluated. A clinical study in patients with colorectal, gastric, pancreatic, or breast cancer receiving capecitabine shows that applying a specific ointment (Alpha) standardized to contain curcumin extract 0.5% and henna extract 10% to the soles and palms twice daily, beginning on day 1 of chemotherapy and continued for 4 cycles, does not prevent acral erythema or improve World Health Organization severity scores when compared with placebo. A post-hoc analysis suggests that there may have been a trend toward delayed onset and progression; however, this study was not structured to assess these outcomes (108874).
• Chemotherapy-induced constipation. It is unclear if oral curcumin reduces symptoms of chemotherapy-induced constipation. Details: A small clinical study in patients with various forms of cancer receiving standard chemotherapy for that cancer type shows that taking curcuminoids (C3 Complex, Sami Labs) 500 mg with piperine (Bioperine) 5 mg twice daily for 9 weeks does not reduce symptoms of constipation when compared with placebo (107111).
• Chemotherapy-induced diarrhea. It is unclear if oral curcumin reduces symptoms of chemotherapy-induced diarrhea. Details: A small clinical study in patients with various forms of cancer receiving standard chemotherapy for that cancer type shows that taking curcuminoids (C3 Complex, Sami Labs) 500 mg with piperine (Bioperine) 5 mg twice daily for 9 weeks does not reduce symptoms of diarrhea when compared with placebo (107111).
• Chemotherapy-induced nausea and vomiting (CINV). It is unclear if oral curcumin reduces CINV. Details: A small clinical study in patients with various forms of cancer receiving standard chemotherapy for that cancer type shows that taking curcuminoids (C3 Complex, Sami Labs) 500 mg with piperine (Bioperine) 5 mg twice daily for 9 weeks modestly reduces symptoms of nausea, but not vomiting, in the second and third months after the start of treatment when compared with placebo (107111).
• Chemotherapy-induced peripheral neuropathy. It is unclear if oral curcumin reduces symptoms of chemotherapy-induced peripheral neuropathy. Details: A small clinical study in patients with various forms of cancer receiving standard chemotherapy for that cancer type shows that taking curcuminoids (C3 Complex, Sami Labs) 500 mg with piperine (Bioperine) 5 mg twice daily for 9 weeks modestly reduces symptoms of chemotherapy-induced peripheral neuropathy over a three-month period when compared with placebo (107111).
• Chronic kidney disease (CKD). It is unclear if oral turmeric is beneficial for CKD. Details: A meta-analysis of four small clinical trials in patients with CKD related to diabetic nephropathy or lupus nephritis shows that taking curcumin or turmeric for 0.5-4 months moderately reduces proteinuria when compared with placebo (109276). Also, a small clinical trial in children and young adults ages 6-25 years with vascular dysfunction related to autosomal dominant polycystic disease (PKD) shows that curcumin powder 25 mg/kg daily for 12 months does not improve vascular function or kidney function when compared with placebo (107117).
• Colorectal adenoma. It is unclear if oral turmeric is beneficial for managing colorectal adenoma. Details: Preliminary clinical research in adults with familial adenomatous polyposis shows that taking curcumin 1500 mg twice daily for 12 months does not reduce the quantity or size of lower intestinal adenomatous polyps when compared with placebo (97427). A very small clinical trial in patients with familial adenomatous polyposis shows that taking 8 capsules daily of a turmeric extract, in a formulation also containing pepper fruit, spirulina, seaweed, and ginger root, for 6 months does not affect total polyp number or burden when compared with placebo. However, both number and burden were modestly reduced in the left colon. Each capsule provided curcuminoids 123.65 mg and turmerones 26.79 mg (110223).
• Colorectal cancer. It is unclear if oral turmeric is beneficial for the prevention or treatment of colorectal cancer. Details: A small clinical trial in patients undergoing chemotherapy following colorectal cancer surgery shows that taking curcuminoids (C3 Complex, Sami Labs) 500 mg with piperine (Bioperine) 5 mg daily for 8 weeks modestly improves some measures of quality of life when compared with placebo (107109). In addition, a small clinical study in people at high risk for colorectal cancer, such as those who smoke, shows that taking the turmeric constituent, curcumin, 4 grams daily for 30 days can reduce the number of precancerous rectal aberrant crypt foci (18204). It is not clear if this results in a reduced risk for colorectal cancer.
• Coronary artery bypass graft (CABG) surgery. One small study suggests that oral turmeric may reduce the risk for myocardial infarction after CABG surgery. Details: Preliminary clinical research shows that taking the turmeric constituent, curcuminoids, 4 grams daily in four divided doses, beginning 3 days prior to surgery and continuing for 5 days post-surgery, decreases the relative risk of myocardial infarction following CABG by approximately 56% when compared with placebo (81143).
• Coronavirus disease 2019 (COVID-19). It is unclear if oral turmeric or its constituent, curcumin, is beneficial for reducing symptoms of COVID-19. Details: Small studies have evaluated curcumin as an adjunctive therapy in adults hospitalized with confirmed COVID-19. Patients in these studies also received treatments such as antimicrobials, anti-inflammatory medications, anticoagulants, antiretrovirals, and immunosuppressants (104966,105393,107119). One study shows that adding curcumin reduces the duration of shortness of breath by 6-9 days when compared with patients who received other treatments in combination with probiotics. However, there were no differences in the duration of other symptoms, including fever, cough, or sore throat. Subgroup analyses suggest that taking curcumin may improve oxygenation and reduce the need for supplemental oxygen or ventilation (105393). Another study shows that adding curcumin modestly reduces the time to resolution of COVID-19 symptoms, the length of supplemental oxygen use, and the likelihood for deterioration in the patients' condition when compared with patients who received other treatments alone (104966). A third study shows some benefit of curcumin on fever and cough when compared with baseline; however, it is unclear if any changes were significant when compared with placebo (107119). Doses of curcumin used in these studies include curcumin 525 mg with piperine 2.5 mg (C3 Complex, SamiDirect) twice daily, starting at admission and continuing for 14 days (105393), or a specific nanocurcumin product (SinaCurcumin, ExirNanoSina) 80 mg twice daily for 2 weeks or 240 mg daily in divided doses for 7 days (104966,107119). Limitations of these studies include the small number of patients with severe symptoms, the large number of outcomes evaluated, the inconsistencies in other treatments used, the lack of clarity related to presentation of some results, and, in most cases, a lack of blinding. Turmeric has also been evaluated in adults in the outpatient setting with suspected or confirmed mild to moderate COVID-19. One small clinical study shows that taking curcumin (SinaCurcumin, ExirNanoSina) 80 mg twice daily for 14 days in addition to other COVID-19 treatments (mainly hydroxychloroquine and azithromycin) reduces the duration of cough, chills, myalgia, and smell and taste disturbance, but not dyspnea, fever, sore throat, or others, by 1-2 days when compared with placebo with other treatments (106802). The validity of this study is limited by the lack of confirmatory diagnosis at baseline and lack of consistency with other treatments, as well as the unclear reporting of symptom duration in relation to the initiation of treatment. Another small clinical study in outpatients confirmed to have COVID-19 shows that taking curcumin 1000 mg plus piperine 10 mg (Sami Labs Limited) daily for 14 days modestly improves weakness, but not cough, pain, headache, difficulty breathing, or biochemical indices, when compared with placebo (109278). Some research has also examined the effect of turmeric as part of a polyherbal combination. Clinical research in patients hospitalized for moderate COVID-19 symptoms shows that using an Ayurvedic formulation 1776 mg twice daily containing turmeric, ashwagandha, ginger, and Boswellia serrata (BV-4051) for 14 days modestly reduces the duration of illness and reduces the severity of fever, cough, and smell and taste dysfunction when compared to placebo. There was no beneficial effect on other symptoms, including nasal congestion, breathing difficulty, headache, and gastrointestinal symptoms. More than half of the patients were also treated with remdesivir which did not impact the majority of these findings (109899).
• Crohn disease. It is unclear if oral turmeric is beneficial for improving symptoms of active Crohn disease. Details: Some clinical research shows that taking the turmeric constituent, curcumin, 1.08 grams daily for one month, then 1.44 grams daily for one month, can reduce bowel movements, diarrhea, and abdominal pain when compared to baseline in patients with Crohn disease (79730). The validity of these findings is limited by the lack of a comparator group.
• Denture stomatitis. Topical turmeric may be beneficial for treating denture stomatitis. Details: A small clinical study in patients with denture stomatitis shows that applying topical curcumin gel (Curenext, Abbott Laboratories) three times daily for 2 weeks resolves denture stomatitis lesions similarly to clotrimazole ointment (106797).
• Diabetes. Low-quality clinical studies suggest that oral curcumin, a constituent of turmeric, may modestly improve glycemic control in patients with diabetes. Details: A meta-analysis of small clinical trials in patients with diabetic kidney disease shows that curcumin reduces levels of fasting glucose by approximately 8.3 mg/dL when compared with placebo. Curcumin was used in doses of 66.3-1670 mg daily for 2-6 months (107114). Preliminary clinical research included in the analysis shows that taking a specific nanoparticle formulation of curcumin (SinaCurcumin, ExirNanoSina) 80 mg daily for 12 weeks reduces fasting blood glucose by about 20 mg/dL (104149). Other meta-analyses of low- to moderate-quality clinical studies in patients with a variety of conditions including type 2 diabetes show that taking turmeric extract, curcumin, or curcuminoids for 4-36 weeks improves glycated hemoglobin (HbA1c) by 0.4-0.7% and reduces fasting glucose by approximately 13 mg/dL when compared with placebo or conventional treatment (106806,108877,113604). The validity of these findings is limited by the heterogeneity of the included studies and broad curcuminoid doses ranging from 46-1500 mg daily. Conversely, other meta-analyses in patients with type 2 diabetes show that curcumin does not reduce HbA1c or insulin levels when compared with placebo (104965,108877,113604).
• Diabetic foot ulcers. It is unclear if oral curcumin is beneficial in patients with diabetic foot ulcers. Details: Preliminary clinical research in patients with grade 3 diabetic foot ulcers shows that taking nanocurcumin 80 mg orally daily for 12 weeks does not improve glycated hemoglobin (HbA1c) or change the rate of ulcer healing when compared with placebo. Taking turmeric did result in modest decreases in fasting blood glucose, insulin levels, and insulin resistance (104972).
• Diabetic nephropathy. It is unclear if oral curcumin is beneficial in patients with diabetic nephropathy. Details: Meta-analyses of two to four small clinical trials in patients with diabetic kidney disease show that curcumin modestly improves serum levels of creatinine, total cholesterol, and fasting glucose, and reduces systolic blood pressure by 4 mmHg, when compared with placebo. However, there was no effect on diastolic blood pressure, proteinuria, or serum levels of other plasma lipids or blood urea nitrogen. Curcumin was used in doses of 66.3-1670 mg daily for 2-6 months (107114). One small study included in this analysis, which evaluated patients receiving hemodialysis, shows that taking a specific nanoparticle formulation of curcumin (SinaCurcumin, ExirNanoSina) 80 mg daily for 12 weeks reduces fasting blood glucose by about 20 mg/dL when compared with placebo (104149).
• Dysmenorrhea. Oral turmeric has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A clinical study in university students aged 18 to 24 in Iran with mild to severe primary dysmenorrhea and premenstrual syndrome (PMS) shows that taking a specific combination product containing curcumin 500 mg plus extract from black pepper 5 mg (C3 Complex, Sami Labs) daily, starting 7 days prior to menstruation and continuing for 3 days after menstruation for 3 consecutive menstrual cycles, does not improve the severity of symptoms when compared with placebo (106805). Conversely, a small clinical study in adults with moderately painful dysmenorrhea shows that taking a single dose of a combination product containing turmeric, Boswellia serrata, and sesame (Rhuleave-K, Arjuna Natural Private Ltd.) 1000 mg at the start of menstruation relieves menstrual cramp pain and reduces pain intensity for up to 6 hours when compared with placebo (112806). However, it is unclear if these effects are due to turmeric, other ingredients, or the combinations.
• Endometriosis. It is unclear if oral turmeric is beneficial for reducing pain due to endometriosis. Details: A small clinical study in adults with endometriosis shows that taking the turmeric constituent, curcumin, 500 mg twice daily for 8 weeks does not affect pain associated with endometriosis or quality of life when compared with placebo (113603).
• Erythema. Although there has been interest in using topical turmeric for reducing erythema, there is insufficient reliable information about the clinical effects of turmeric for this purpose.
• Exercise-induced muscle soreness. It is unclear if oral turmeric is beneficial for reducing muscle soreness from exercise. Details: A small clinical study in healthy males shows that taking turmeric capsules containing curcumin 2.5 grams twice daily for 5 days, starting 2.5 days before exercise, slightly reduces pain from certain movements when compared with placebo (98998). Another small crossover clinical study in professional male soccer players shows that taking curcumin 500 mg (Elite Opti-Turmeric, Health Span) immediately, 12 hours, and 36 hours after a match accelerates muscle recovery and reduces delayed-onset muscle soreness when compared with medium chain triglyceride oil 1000 mg (111356). Turmeric has also been examined in combination with other ingredients. Clinical research in healthy active adults with moderate to severe exercise-induced muscle pain shows that taking a single, 1000-mg dose of turmeric and Boswellia serrata extracts in black sesame oil (Rhuleave-K; Arjuna Natural Private Ltd.) improves pain relief when compared with placebo, with maximal benefits within about 3 hours. The number of people needed to treat to obtain pain relief of at least 50% over a 6-hour period was 1.1 (109277).
• Gingivitis. Small clinical studies suggest that oral turmeric and turmeric mouthwash may reduce the severity of gingivitis. Turmeric mouthwash appears to be similarly effective to chlorhexidine mouthwash. Details: A meta-analysis of generally preliminary clinical research shows that rinsing with a mouthwash containing curcumin for 3-4 weeks is as effective as rinsing with chlorhexidine for reducing the severity of gingivitis or plaque (106059). Mouthwashes in these studies contained 0.05% to 20% curcumin and were usually used twice daily for 3-4 weeks (81127,89723,106059). One mouthwash contained 0.05% turmeric extract and 0.005% eugenol (89723). Another small clinical trial shows that taking a specific nanoparticle formulation of curcumin (SinaCurcumin, ExirNanoSina) 80 mg daily by mouth after breakfast for 4 weeks reduces the severity of gingivitis and gingival bleeding, but not plaque, when compared with placebo in patients with gingivitis and mild periodontitis (104146).
• Gout. Although there is interest in using oral turmeric for gout, there is insufficient reliable information about the clinical effects of turmeric for this condition.
• Gulf war syndrome. It is unclear if oral curcumin is beneficial in patients with Gulf war syndrome. Details: A small preliminary clinical trial in patients with Gulf war syndrome shows that taking curcumin (Meriva, Indena, S.p.A.) 500 mg twice daily for 30 days reduces overall symptoms, including pain, fatigue, gastrointestinal distress, and others, by 19% when compared with baseline. Taking a higher dose of 2000 mg twice daily for an additional 30 days appears to be no more effective than the lower dose (105395).
• Helicobacter pylori. Small clinical studies suggest that oral turmeric is not beneficial for eradicating H. pylori when used alone or in combination with standard triple therapy or famotidine. Details: One small clinical study in patients with H. pylori gastritis shows that taking turmeric 2.1 grams daily for 4 weeks is less effective for eradicating H. pylori than taking an omeprazole-based triple regimen for one week (80957). Another small study in adults with peptic ulcers shows that taking a specific curcumin product (C3 Complex, Sami Labs LTD) 500 mg daily for 7 days, in conjunction with standard triple therapy, does not improve H. pylori eradication rates when compared with standard triple therapy alone. The addition of curcumin increased the resolution of dyspepsia symptoms by an additional 21%, but the clinical significance of this outcome is unclear (97420). In patients with dyspepsia, most of whom tested positive for fecal H. pylori antigen, clinical research shows that taking curcuminoids (C3 Complex, Sami Labs) 500 mg with piperine (Bioperine) 5 mg daily in addition to famotidine 40 mg daily for 30 days is no more effective for reducing fecal H. pylori antigen levels than taking famotidine alone (106063).
• Hypertension. It is unclear if oral curcumin is beneficial in patients with hypertension. Details: A meta-analysis of approximately 30 clinical studies in healthy adults or patients with a variety of conditions shows that taking turmeric, curcumin, curcuminoids, or nano-curcumin for 4 to 24 weeks reduces systolic blood pressure by about 2 mmHg and diastolic blood pressure by about 0.8 mmHg when compared with placebo (113602). However, these blood pressure reductions may not be clinically meaningful. In addition, most of the included studies were small and utilized heterogeneous dosing regimens.
• Impaired glucose tolerance (prediabetes). Oral turmeric may modestly improve glucose control in some patients with prediabetes. Details: In overweight or obese individuals with prediabetes, clinical research shows that taking a turmeric extract (BCM95 or Cucugreen; M/s Arjuna Natural Pvt Ltd.) 500 mg daily, providing 95% curcuminoids and at least 65% curcumin, for 90 days, either alone or in combination with zinc 30 mg as zinc gluconate, results in a small reduction in fasting glucose and glycated hemoglobin (HbA1c) when compared with placebo. There was also a small benefit in insulin sensitivity (105391). Other preliminary clinical research in adults with prediabetes shows that taking 500 mg of a combination of turmeric extract and Indian gooseberry extract in a 1:2 ratio along with phosphatidylcholine (EmbliQur) twice daily for 6 months modestly reduces fasting glucose and improves insulin resistance, when compared with placebo. However, changes in most other endpoints were not significantly different from placebo. Each 500 mg capsule contained turmeric extracts 29.86% and turmeric oil 1.27% (113355). The effect of turmeric on progression to type 2 diabetes in patients with prediabetes has also been investigated. Preliminary clinical research shows that taking a turmeric extract containing curcumin 750 mg twice daily for 9 months reduces the percentage of patients with prediabetes who develop type 2 diabetes when compared with placebo (81163).
• Irritable bowel syndrome (IBS). It is unclear if oral turmeric is beneficial for improving symptoms of IBS. Details: Preliminary clinical research in otherwise healthy adults with IBS shows that taking a turmeric extract (Cynara Turmeric, Lichtwer Pharma) 72-144 mg daily for 8 weeks reduces IBS symptoms by about 40% to 60% when compared to baseline (79565). The validity of this finding is limited by the lack of a comparator group. Taking a combination product (CU-FEO, Alfa Wasserman S.p.A.) containing curcumin 42 mg and fennel essential oil 25 mg per capsule twice daily for 60 days improves overall ratings of abdominal pain, abdominal distention, and quality of life by 24% when compared with placebo (97422). It is unclear if these effects are due to turmeric, fennel, or the combination. Observational research suggests that adding a supplement (Enterofytol PLUS) providing curcumin 42 mg and berberine 200 mg twice daily for 2 months to conventional IBS treatment is associated with improvements in symptoms, such as abdominal discomfort, distension, and stool status, by up to 48% when compared with conventional treatment alone. Use of the supplement was also associated with a 64% reduced need for conventional treatments (113354).
• Joint pain. Oral turmeric has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Clinical research shows that taking capsules of a specific combination product (Instaflex Joint Support, Direct Digital) containing glucosamine sulfate 1500 mg, methylsulfonylmethane 500 mg, white willow bark extract 250 mg, ginger root concentrate 50 mg, Boswellia extract 125 mg, turmeric root extract 50 mg, cayenne 40 m H.U. 50 mg, and hyaluronic acid 4 mg in three divided doses daily for 8 weeks reduces joint pain severity by 37% compared to only 16% with placebo. However, it does not improve joint stiffness or function when compared with placebo (89560). It is unclear if these effects are due to turmeric, other ingredients, or the combination.
• Juvenile idiopathic arthritis (JIA). Although there is interest in using oral turmeric for JIA, there is insufficient reliable information about the clinical effects of turmeric for this condition.
• Knee pain. It is unclear if oral turmeric is beneficial for knee pain. Details: Clinical research in individuals with knee pain not related to existing arthritis shows that taking turmeric extract (TurmXTRA 60N; Inventia Healthcare Ltd. and Laila Nutraceuticals) 250 mg, providing 60% curcuminoids, once daily for 90 days modestly reduces pain associated with walking 80 meters when compared with placebo. The time taken to walk 80 meters and to climb nine steps was reduced by 4-5 seconds (105396).
• Lichen planus. Evidence is conflicting on whether turmeric is beneficial for lichen planus. Details: A meta-analysis of several small, heterogeneous, mostly low-quality clinical and observational studies in adults with oral lichen planus shows that oral or topical curcumin with or without corticosteroids for 2-12 weeks does not improve erythema, lesion size, or pain when compared with control (113605). Similarly, a network meta-analysis of small clinical trials in patients with oral lichen planus shows that applying topical turmeric gel does not improve symptoms, clinical resolution, clinical scores, or reduce pain when compared with other available interventions (111640). However, small individual clinical studies have shown some benefit in using turmeric for lichen planus. A small clinical study shows that taking a specific turmeric extract (Curcumin C3 Complex, Sabinsa Corporation) containing curcuminoids 6000 mg daily in three divided doses for 12 days can reduce erythema and ulceration associated with lichen planus when compared with placebo (81109). Another small clinical study shows that taking a nanocurcumin product (SinaCurcumin, ExirNanoSina) 80 mg orally once daily for 1 month reduces oral lichen planus lesion size, pain, and burning similarly to prednisolone 10 mg taken orally once daily for 1 month (104961).
• Metabolic syndrome. It is unclear if oral turmeric is beneficial for metabolic syndrome. Details: Research is conflicting on how turmeric, curcumin, and other formulations affect various measures of metabolic syndrome. Some clinical research and a meta-analysis of 13 clinical studies in patients with metabolic syndrome show that taking turmeric or curcumin decreases low-density lipoprotein (LDL) cholesterol, waist circumference by 2 cm, fasting blood glucose by 9 mg/dL, and diastolic blood pressure by 3 mmHg and increases high-density lipoprotein (HDL) cholesterol by 5 mg/dL when compared with placebo. However, other research shows that turmeric or curcumin have no effect on body weight, lipids, blood pressure, or blood glucose when compared with placebo (98999,99311,105400,109284,111347,112118). The validity of these effects is limited by high heterogeneity within the included studies and incomplete information about randomization and blinding. Studies have used turmeric, curcumin, and curcumin extract 80-2400 mg, in divided doses, daily for 4-12 weeks, nano-curcumin 80 mg daily for 12 weeks, or calebin A (CurCousin, Sabinsa), which is a constituent of turmeric, 25 mg twice daily for 3 months (98999,99311,105400,109284,111347,112118). Also, taking crude or phosphorylated curcuminoids 1 gram daily for 6 weeks does not improve sleep or reduce weight in these patients (105397).
• Migraine headache. It is unclear if oral curcumin is beneficial for migraine headache. Details: A small clinical trial in females with regular migraines shows that taking curcumin 500 mg twice daily for 8 weeks reduces the severity and duration, but not the frequency, of migraine headaches when compared with placebo. In individuals taking curcumin, the duration of headache per month was reduced by approximately 10.3 hours from baseline (107116).
• Myocardial infarction (MI). It is unclear if oral curcumin is beneficial for reducing myocardial injury following a MI. Details: Clinical research in patients with an acute MI shows that taking curcuminoids 500 mg plus piperine (Bioperine) 5 mg daily (Sami Labs) for 8 weeks does not improve ejection fraction, serum levels of cardiac troponin 1, blood pressure, levels of fasting blood glucose, or kidney function parameters when compared to placebo. However, there were some modest benefits on levels of low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, glycated hemoglobin, and certain liver enzymes such as aspartate aminotransferase (AST) and alkaline phosphatase (ALP) (107115). The validity of this study is limited by its short duration and relatively small sample size.
• Obesity. Oral turmeric might modestly improve weight loss, although any effect is unlikely to be clinically significant. Details: Multiple meta-analyses of small, mostly low-quality clinical studies in adults with a variety of comorbid conditions show that taking various forms and doses of turmeric or curcumin results in an average weight loss of about 0.6-1 kg, a decrease in body mass index (BMI) of about 0.2-0.5 kg/m2, and a decrease in waist circumference of about 1.3 cm when compared with control (102345,111351,111352). A sub-analysis of dose and duration shows that a reduction in waist circumference only occurs with curcumin daily doses above 1000 mg, and duration of treatment longer than 8 weeks (102345).
• Oral submucous fibrosis. Small studies suggest that topical or oral curcumin might be beneficial for oral submucous fibrosis. However, the research is heterogenous with respect to outcomes, comparators, and the turmeric preparations, doses, and routes of administration utilized. Details: A meta-analysis of 3 small clinical trials shows that turmeric modestly improves mouth opening when compared with control. In addition, a systematic review of 11 studies shows that turmeric improves overall symptoms, including mouth opening, tongue protrusion, burning sensation, and cheek flexibility. However, studies were small with short duration and used variable dosing strategies. Most trials have studied oral turmeric 300-400 mg, either alone or with black pepper 100 mg or piperine 5 mg, for 3-6 months. Less commonly, turmeric was provided in lozenge form (105399). Also, a network meta-analysis suggests that the turmeric constituent curcumin with or without piperine is most the effective for reducing tongue protrusion when compared indirectly with various medical and antioxidant therapies; however, this analysis suggests that curcumin does not rank among the most effective interventions for improving mouth opening, burning sensation, or cheek flexibility (113514). Other preliminary clinical research shows that taking a specific oral product containing curcumin 300 mg and piperine 5 mg (Turmix tablets, Sanat Products), three times daily for 12 weeks, improves mouth opening, burning sensation, and tongue protrusion when compared with baseline, but not when compared with an antioxidant product containing alpha-lipoic acid, beta-carotene, copper, lycopene, selenium, and zinc. Mouth opening is further improved by concurrent use of a mouthwash (Turmix mouthwash, Sanat Products), containing 0.1% w/v turmeric extract (standardized to 95% curcumin), with thymol, eucalyptol, clove oil, mentha oil, and tea tree oil, twice daily for 12 weeks (102347). A small clinical study shows that applying topical curcumin gel (Curenext, Abbott Laboratories) 5 mg daily in 3-4 divided doses for 6 weeks, in combination with oral physical therapy, improves mouth opening similarly to using an aloe vera gel in combination with oral physical therapy. However, decreases in burning sensation are greater with aloe gel than curcumin gel (104967). It is not clear whether the gels, oral physical therapy, or the combination of both is responsible for the outcome. Finally, clinical research shows that applying a paste providing turmeric and holy basil 10 grams each, mixed in 10 mL of honey, to the oral mucosa 4 times daily for 3 months modestly improves mouth opening, tongue protrusion, and burning sensation and reduces the presence of fibrous bands when compared with taking a vitamin B supplement. There was no effect on the shape of the uvula (113325).
• Pain (acute). Oral turmeric has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research in adults with acute musculoskeletal pain shows that taking a specific combination product containing turmeric and Boswellia serrata extracts in black sesame oil (Rhuleave-K; Arjuna Natural Private Ltd.) 1000 mg daily for 7 days is as effective as acetaminophen 1000 mg daily for pain relief, onset of pain relief, and onset of maximal pain relief (109287). This study is limited by its lack of blinding and placebo control. Additionally, the dose of acetaminophen used in this study is below the standard recommended daily dose.
• Periodontitis. There is limited evidence on the oral or topical use of turmeric or its constituent curcumin in patients with periodontitis. Details: A meta-analysis of heterogenous clinical studies in patients with chronic periodontitis suggests that use of local delivery gel products, usually turmeric 2% or a specific product containing curcumin (Curenext), modestly reduces pocket depth when compared with routine products, such as chlorhexidine. However, limited research suggests that curcumin products do not affect plaque or gingivitis measures, and curcumin irrigation does not affect pocket depth based on limited research (107108). A small preliminary clinical study in patients with severe chronic periodontitis shows that placing curcumin gel 2 mg on one side of the mouth along with scaling and root planing (SRP) reduces plaque and probing pocket depth, but not gingival index, when compared with SRP alone (101339). The use of oral curcumin has also been investigated. A small clinical trial in patients with gingivitis and mild periodontitis shows that taking a specific nanoparticle formulation of curcumin (SinaCurcumin, ExirNanoSina) 80 mg daily after breakfast for 4 weeks reduces the severity of gingivitis and gingival bleeding, but not plaque, when compared with placebo (104146).
• Physical performance. It is unclear if oral turmeric may be beneficial for improving physical performance in older adults. Details: A very small clinical study in moderately functioning, sedentary adults over age 65 with low-grade chronic inflammation shows that that taking a specific turmeric extract (Curcumin C3 Complex, Sabinsa Corporation) 500 mg twice daily for 12 weeks does not improve measures of physical function, walking speed, or muscle strength when compared with placebo (111357). However, this study may have been inadequately powered to detect any possible differences between groups.
• Polycystic ovary syndrome (PCOS). Small clinical studies suggest that oral curcumin may improve some metabolic parameters in patients with PCOS, but these improvements may not be considered clinically significant. Details: Clinical research in patients with PCOS shows that taking curcumin 500 mg one to three times daily for 6-12 weeks improves some metabolic parameters (104968,105394,106795). Conversely, a small clinical study in patients aged 18 to 45 with PCOS in Iran shows that taking curcumin 1000 mg daily for 12 weeks modestly reduces fasting glucose but does not improve other metabolic parameters when compared with placebo. Taking curcumin also did not improve testosterone levels or hirsutism scores (111355). Meta-analyses show that taking curcumin modestly decreases body mass index (BMI) and improves measures of glycemic control, including fasting glucose and insulin resistance, and levels of total cholesterol when compared with placebo or metformin alone. However, effects on high-density lipoprotein (HDL) cholesterol levels were mixed and there was no effect on low-density lipoprotein (LDL) cholesterol or triglyceride levels (105394,106795,110219). Other preliminary clinical research shows that taking curcumin decreases plasma dehydroepiandrosterone and fasting plasma glucose levels when compared with placebo (104968). Some clinical research also shows that taking nano-curcumin (SinaCurcumin, ExirNanoSina) 80 mg daily for 3 months is beneficial in patients already taking metformin 1500 mg daily. Taking curcumin had modest beneficial effects on fasting insulin and insulin resistance, as well as levels of testosterone, LDL cholesterol, HDL cholesterol, and triglycerides, when compared with metformin alone. There was no effect of curcumin on body weight, fasting blood glucose, or other hormones (106060).
• Postoperative pain. Small clinical studies suggest that oral curcumin, a constituent of turmeric, may modestly reduce pain in various postoperative recovery settings. Details: One small clinical study in patients undergoing laparoscopic cholecystectomy shows that taking curcumin 2 grams daily reduces postoperative pain, fatigue, and the need for analgesics by the second postoperative week when compared with placebo (81099). In patients undergoing surgery for inguinal hernia and/or hydrocele, taking curcumin 1.2 grams daily for 5 days reduces inflammation and tenderness by the sixth postoperative day when compared with placebo (81206). Curcumin was taken in 3-4 divided doses daily in these studies. Finally, taking a single dose of curcumin 200 mg after surgical removal of impacted third molars modestly reduces acute postoperative pain when compared with taking mefenamic acid 500 mg (99305).
• Premenstrual syndrome (PMS). It is unclear if oral turmeric may be beneficial for improving symptoms of PMS. Details: Some preliminary clinical research in patients with PMS shows that taking curcumin 100 mg twice daily, starting 7 days prior to menstruation and continuing for 3 days after menstruation, improves physical, behavioral, and mood symptoms, as well as overall severity of symptoms, when compared with placebo (97433). Conversely, in university students aged 18 to 24 in Iran with mild to severe PMS and primary dysmenorrhea, a clinical study shows that taking a specific combination product containing curcumin 500 mg plus extract from black pepper 5 mg (C3 Complex, Sami Labs) daily, starting 7 days prior to menstruation and continuing for 3 days after menstruation for 3 consecutive menstrual cycles, does not improve the severity of symptoms when compared with placebo (106805).
• Prostate cancer. It is unclear if oral turmeric is beneficial for the prevention or treatment of prostate cancer. Details: One small clinical study shows that taking curcumin 1.8 grams orally three times daily for 7 days, starting 4 days prior to docetaxel and prednisone treatment and continuing for up to 6 cycles, reduces PSA levels by at least half in 59% of patients when compared to baseline. Also, all patients with measurable lesions showed at least stable disease after treatment, and 40% of patients showed partial response when compared with baseline (96132). It is unclear if the addition of turmeric is beneficial when compared with docetaxel and prednisone alone. In contrast, an additional small clinical trial shows that taking curcumin 6 grams daily for 7 days every 3 weeks, starting four days before docetaxel, does not improve PSA levels or progression-free or overall survival when compared with docetaxel alone (105392).
• Psoriasis. Evidence is limited to one small study of topical use in patients with scalp psoriasis. Details: Preliminary clinical research in adults with scalp psoriasis shows that applying a tonic of turmeric to the scalp twice daily for 9 weeks modestly improves overall symptoms and quality of life when compared with a placebo tonic (97429).
• Quality of life. Some preliminary clinical research suggests that oral curcumin might improve quality of life in patients with various chronic conditions. Details: Small or low-quality clinical trials in various patient populations show that taking curcumin improves at least some measures of quality of life when compared with placebo. Research has been conducted in patients with cancer, sulfur mustard-induced chronic pruritus, benign prostatic hyperplasia (BPH), or irritable bowel syndrome (IBS). Studies have evaluated curcumin 2250 mg once daily for 6 months, a specific combination product (C3 Complex, Sami Labs LTD) containing curcumin 500-1000 mg plus piperine (Bioperine) daily for 4-9 weeks, or a combination product (CU-FEO, Alfa Wasserman S.p.A.) containing curcumin 42 mg and fennel essential oil 25 mg per capsule twice daily for 60 days (81120,81176,97422,106799,107109,107111). Also, in patients with scalp psoriasis, applying a tonic of turmeric to the scalp twice daily for 9 weeks modestly improves quality of life when compared with a placebo tonic (97429).
• Radiation dermatitis. It is unclear if oral or topical turmeric is beneficial for reducing the severity of radiation dermatitis. Details: A meta-analysis of 4 clinical studies in patients with breast cancer shows that taking curcumin 500-2000 mg three times daily for 3-7 weeks or applying curcumin gel 500 mg three times daily for 7 weeks reduces the radiation dermatitis severity score by about 0.5 points (on a 4-point scale) when compared with placebo or other control (111354). The validity of this analysis is limited by the heterogeneity of the included studies. However, a small clinical study in patients with breast cancer shows that taking nanocurcumin 80 mg twice daily during and for up to 2 weeks after treatment does not reduce skin reaction severity overall, but does modestly reduce pain, when compared with taking placebo. Also, there was a small reduction in skin reaction severity near the end of the study. All patients also used aloe vera leaf as part of the hospital protocol (109281). Another small preliminary clinical study in head and neck cancer patients shows that a specific cream (Vicco turmeric cream, Vicco Laboratories) containing turmeric and sandalwood oil, applied 5 times daily during radiation therapy, seems to reduce frequency and severity of radiation dermatitis when compared with baby oil (99307).
• Radiation proctopathy. It is unclear if oral turmeric is beneficial for preventing proctitis or cystitis in patients receiving radiotherapy for prostate cancer. Details: A small clinical study in patients with prostate cancer shows that taking a specific nanocurcumin product (SinaCurcumin, ExirNanoSina) 120 mg daily, for 3 days before and also during a course of radiotherapy, does not reduce the occurrence of proctitis or cystitis when compared with placebo (100259). This study may have been underpowered to detect small treatment effects.
• Respiratory tract infections. Although there is interest in using oral turmeric for various respiratory tract infections, including bronchitis and the common cold, it has not been clinically evaluated.
• Rheumatoid arthritis (RA). Small clinical studies suggest that oral curcumin, a constituent of turmeric, may modestly improve some symptoms of RA. Details: Meta-analyses of small clinical trials in patients with RA show that taking curcumin alone or with other treatments modestly reduces overall RA symptoms, pain, and markers of inflammation when compared with control groups, including placebo or other treatments. However, some research shows that there is no beneficial effect on tender or swollen joint count from the limited available clinical research (109280,111358), while other research shows that there is a benefit (112117). Clinical studies have evaluated curcumin 120-1200 mg daily for 2 weeks to 3 months (11149,18205,96129). The validity of these findings is limited by the small size of the studies, and in some cases, the lack of a comparator group.
• Sarcopenia. Oral turmeric has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research in elderly patients with sarcopenia shows that taking a specific slow-release product containing turmeric, protein, carbohydrate, and fiber (Cureit, Aurea Biolabs), 500 mg orally daily for 3 months, increases handgrip strength by about 1% and distance walked before feeling tired by about 6% when compared with placebo. It also increases weightlifting capacity by about 6% from baseline, compared with a 5% decrease from baseline in those taking placebo (104973). It is unclear whether these small changes are clinically meaningful.
• Schizophrenia. Although there is interest in using oral turmeric for improving cognitive function in patients with schizophrenia, there is insufficient reliable information about the clinical effects of turmeric for this use.
• Sepsis. It is unclear if oral curcumin, a constituent of turmeric, is beneficial in patients with sepsis. Details: A small clinical trial in patients admitted to the intensive care unit (ICU) with sepsis shows that a specific nanoparticle formulation of curcumin (SinaCurcumin, ExirNanoSina), 80 mg dissolved in water and administered via gastric tube following lavage twice daily for 10 days does not affect length of ICU stay, Acute Physiology and Chronic Health Evaluation II (APACHE II) scores, blood pressure, or heart rate when compared with placebo (108873).
• Smoking cessation. Oral turmeric has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A moderate-sized clinical study in adults with a history of smoking 5 or more cigarettes daily for at least 3 years shows that taking a specific combination product containing turmeric 50 mg, ashwagandha, Indian gooseberry, tribulus, bacopa, Albizia lebbeck, licorice, clove, ginger, cowhage, and holy basil (Smotect, Smotect India) daily for 3 months reduces the number of cigarettes smoked by approximately 3 per day when compared with placebo. This product also reduces levels of alveolar carbon monoxide and carboxyhemoglobin but does not improve lung capacity (112115). However, only data from patients who completed treatment were analyzed, which limits the validity of this study. It is unclear if these effects are due to turmeric, other ingredients, or the combination.
• Stress. It is unclear if oral turmeric is beneficial for reducing occupational stress in healthy adults. Details: A small clinical trial in healthy adults with occupational stress-related anxiety and fatigue shows that taking a specific type of turmeric (CurQfen, Akay Flavours and Aromatics Pvt Ltd.) that contains fenugreek dietary fiber for improved bioavailability at a dose of 500 mg twice daily for 30 days reduces stress and fatigue and improves quality of life when compared with placebo, and also when compared with a standard curcumin supplement with lower bioavailability (99308).
• Stroke. It is unclear if oral turmeric is beneficial for stroke. Details: A small clinical study conducted in Iran in adults with a recent ischemic stroke shows that taking curcumin 500 mg and piperine, a pepper constituent, 5 mg (Sami Lans, India) daily for 12 weeks reduces carotid intima-media thickness, triglycerides, total cholesterol, and systolic and diastolic blood pressure, but does not improve low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, or quality-of-life indicators when compared with placebo (113601). The validity of this study is limited by the lack of statistical adjustment for multiple comparisons which can lead studies to erroneously show differences between treatment groups.
• Systemic lupus erythematosus (SLE). There is limited evidence on the oral use of turmeric in adults with lupus nephritis. Details: Preliminary clinical research in adults with lupus nephritis shows that taking turmeric 1.5 grams daily in three divided doses for 3 months reduces systolic blood pressure and improves kidney function when compared to baseline (81104). The validity of this finding is limited by the lack of a comparator group.
• Tuberculosis. It is unclear if oral turmeric is beneficial in patients receiving treatment for tuberculosis. Details: A small clinical study in adults receiving antituberculosis treatment shows that taking a formulation containing turmeric 0.5 grams and Tinospora cordifolia 0.5 grams twice daily for 4 months can reduce levels of Mycobacterium tuberculosis in the sputum and improve lesion healing when compared with antituberculosis treatment alone. Also, liver toxicity associated with the antituberculosis treatment seems to be reduced when administered with this formulation (80424). It is unclear if these effects are due to turmeric, Tinospora cordifolia, or the combination.
• Ulcerative colitis. It is unclear if oral or rectal turmeric, or its constituent, curcumin, is beneficial in adults with ulcerative colitis. Details: Although two small clinical studies in adults with ulcerative colitis show that taking oral turmeric extract 2-3 grams daily for 1-6 months improves the rate of remission and reduces relapse rate (79966,97423), a meta-analysis of these studies and one additional clinical study shows that turmeric does not improve remission rates when compared with placebo (99000). A specific product (Cur-Cure, Bara Herbs Inc) was used in some of these studies. Reasons for the conflicting findings are unclear, but may be due to small patient populations, concerns about blinding, and the inclusion of patients who were also taking immunomodulating drugs. It may also be due to differences in how a study measures remission. A meta-analysis of small clinical studies in patients with mild to moderate ulcerative colitis shows that adding oral curcumin 0.5-3 grams daily to standard treatment for 1-6 months may improve clinical remission rates, but not endoscopic remission rates, when compared with placebo (108872). However, the validity of this finding is limited by the small number of studies that evaluated endoscopic remission. A small clinical study shows that administering an enema form of turmeric extract (NCB-02, Himalaya Drug Company) as 20 mL, containing turmeric extract 140 mg, daily for 8 weeks increases response rate from 50% to about 93% and increases remission rate from about 31% to 71% when compared with placebo in patients with active ulcerative colitis. However, patients using the turmeric extract enema for shorter durations did not improve when compared with placebo (89729). Turmeric has also been investigated in combination with the Mediterranean diet. A small clinical trial shows that taking curcumin (VeNatura Curcumin Supplement) 800 mg twice daily while following the Mediterranean diet for 8 weeks is no more effective for improving ulcerative colitis symptom severity than following the Mediterranean diet without supplemental curcumin (113339).
• Uveitis. It is unclear if oral curcumin is beneficial for uveitis. Details: Observational research in patients with acute non-infectious uveitic macular edema shows that taking a specific hydrophilic curcumin product (Cucrcuwin, Diabec, Alfa Intes) 60 mg twice daily for 6 months, in conjunction with standard corticosteroid treatment, and then alone for an additional 6 months, modestly improves best corrected visual acuity, but not macular thickness or intraocular pressure, when compared with standard treatment alone for 6 months (107110).
• Wound healing. Although there is interest in using topical turmeric for wound healing, there is insufficient reliable information about the clinical effects of turmeric for this condition. More evidence is needed to rate turmeric for these uses.

(Read more about TURMERIC)

LIKELY SAFE ...when used orally in amounts commonly found in foods. Black pepper has Generally Recognized as Safe (GRAS) status in the US (4912).

POSSIBLY SAFE ...when black pepper oil is applied topically. Black pepper oil is nonirritating to the skin and is generally well tolerated (11). ...when black pepper oil is inhaled through the nose or as a vapor through the mouth, short-term. Black pepper oil as a vapor or as an olfactory stimulant has been used with apparent safety in clinical studies for up to 3 days and 30 days, respectively (29159,29160,29161,90502). There is insufficient reliable information available about the safety of black pepper when used orally in medicinal amounts.

CHILDREN: LIKELY SAFE
when used orally in amounts commonly found in foods (11).

CHILDREN: POSSIBLY UNSAFE
when used orally in large amounts. Fatal cases of pepper aspiration have been reported in some patients (5619,5620). There is insufficient reliable information available about the safety of topical pepper oil when used in children.

PREGNANCY: LIKELY SAFE
when used orally in amounts commonly found in foods (11).

PREGNANCY: LIKELY UNSAFE
when used orally in large amounts. Black pepper might have abortifacient effects (11,19); contraindicated. There is insufficient reliable information available about the safety of topical pepper when used during pregnancy.

LACTATION: LIKELY SAFE
when used orally in amounts commonly found in foods (11). There is insufficient reliable information available about the safety of black pepper when used in medicinal amounts during breast-feeding.

(Read more about BLACK PEPPER)

LIKELY SAFE ...when consumed orally in moderate amounts (1452,9222,9223,9224,9228,9233,9234,9235,9236,36376)(36426,36434,36436,36581). Black tea contains caffeine. According to a review by Health Canada, and a subsequent large meta-analysis conducted in the US, drinking up to 4 cups of black tea daily, or approximately 400 mg of caffeine, is not associated with significant adverse cardiovascular, bone, behavioral, or reproductive effects in healthy adults (11733,98806). The US Dietary Guidelines Advisory Committee states that there is strong and consistent evidence that consumption of caffeine 400 mg daily is not associated with increased risk of major chronic diseases, such as cardiovascular disease or cancer, in healthy adults (98806).

POSSIBLY UNSAFE ...when consumed orally long term or in high amounts. Black tea contains a significant amount of caffeine. Chronic use, especially in large amounts, can produce tolerance, habituation, psychological dependence, and other significant adverse effects. Doses of caffeine greater than 600 mg per day, or approximately 6 cups of black tea, have been associated with significant adverse effects such as tachyarrhythmias and sleep disturbances (11832). These effects would not be expected to occur with the consumption of decaffeinated black tea. Keep in mind that only the amount of ADDED caffeine must be stated on product labels. The amount of caffeine found in ingredients such as black tea, which naturally contains caffeine, does not need to be provided. This can make it difficult to determine the total amount of caffeine in a given product.

LIKELY UNSAFE ...when consumed orally in very high amounts. The fatal acute oral dose of caffeine is estimated to be 10-14 grams (150-200 mg per kilogram). Serious toxicity can occur at lower doses depending on variables in caffeine sensitivity such as smoking, age, prior caffeine use, etc. (11832).

CHILDREN: POSSIBLY SAFE
when used in food and beverage amounts (4912,11833).

PREGNANCY: POSSIBLY SAFE
when used orally in moderate amounts. Due to the caffeine content of black tea, mothers should closely monitor their intake to ensure moderate consumption. Caffeine crosses the human placenta but is not considered a teratogen. Fetal blood concentrations of caffeine approximate maternal concentrations (4260). The use of caffeine during pregnancy is controversial; however, moderate consumption has not been associated with clinically important adverse fetal effects (2708,2709,2710,2711,9606,11733,16014,16015,37802,37584). In some studies, consuming amounts over 200 mg daily is associated with a significantly increased risk of miscarriage (16014). This increased risk may be most likely to occur in females with genotypes that confer a slow rate of caffeine metabolism (98806). According to a review by Health Canada, and a subsequent large meta-analysis conducted in the US, most healthy patients can safely consume doses up to 300 mg daily during pregnancy without an increased risk of spontaneous abortion, stillbirth, preterm birth, fetal growth retardation, or congenital malformations (11733,98806). Advise keeping caffeine consumption below 300 mg daily. This is similar to the amount of caffeine in about 3 cups of black tea. Keep in mind that only the amount of ADDED caffeine must be stated on product labels. The amount of caffeine found in ingredients such as black tea, which naturally contains caffeine, does not need to be provided. This can make it difficult to determine the total amount of caffeine in a given product.

PREGNANCY: POSSIBLY UNSAFE
when used orally in large amounts. Caffeine from black tea crosses the placenta, producing fetal blood concentrations similar to maternal levels (4260). Consumption of caffeine in amounts over 300 mg daily is associated with a significantly increased risk of miscarriage (16014,98806). Advise keeping caffeine consumption from all sources below 300 mg daily. This is similar to the amount of caffeine in about 3 cups of black tea. High doses of caffeine throughout pregnancy have resulted in symptoms of caffeine withdrawal in newborn infants (9891). High doses of caffeine have also been associated with spontaneous abortion, premature delivery, and low birth weight (2709,2711,24995,24998,37561,37898,38012,38186,38199,38212)(38285,38290). Preliminary evidence from a population study also suggests that increasing consumption of black tea might increase the risk of spina bifida (15112); however, this finding needs to be verified with additional research. Cohort studies suggest that consuming large amounts of caffeine during pregnancy may reduce the height and weight of the infants born as they grow up. In a cohort of mother/infant pairs with a median maternal plasma caffeine level of 168.5 ng/mL (range 29.5-650.5 ng/mL) during pregnancy, birth weights and lengths were lower in the 4th quartile of caffeine intake compared with the 1st. By age 7, heights and weights were lower by 1.5 cm and 1.1 kg respectively. In another cohort of mother/infant pairs with higher maternal pregnancy plasma caffeine levels, median 625.5 ng/mL (range 86.2 to 1994.7 ng/mL), heights at age 8 were 2.2 cm lower, but there was no difference in weights (109846). Keep in mind that only the amount of ADDED caffeine must be stated on product labels. The amount of caffeine found in ingredients such as black tea, which naturally contains caffeine, does not need to be provided. This can make it difficult to determine the total amount of caffeine in a given product. More evidence is needed to determine the safety of using black tea during pregnancy. For now, advise avoidance of large quantities of black tea during pregnancy.

LACTATION: POSSIBLY SAFE
when used orally in moderate amounts. Due to the caffeine content of black tea, caffeine intake should be closely monitored. Breast milk concentrations of caffeine are thought to be approximately 50% of maternal serum concentrations. Minimal consumption would likely result in limited exposure to a nursing infant (9892).

LACTATION: POSSIBLY UNSAFE
when used orally in large amounts. Consumption of black tea might cause irritability and increased bowel activity in nursing infants (6026). Black tea might also interfere with iron metabolism and folic acid bioavailability in nursing infants (631,53782). Large doses or excessive intake of black tea should be avoided during lactation.

(Read more about BLACK TEA)

LIKELY SAFE ...when used orally in amounts commonly found in foods. Cardamom has Generally Recognized as Safe (GRAS) status in the US (4912).

POSSIBLY SAFE ...when used orally in medicinal amounts, short-term. Cardamom powder 3 grams daily in 2-3 divided doses has been used with apparent safety for up to 16 weeks (95308,95597,101885,107920). ...when the essential oil is used by inhalation for aromatherapy (77054,95307).

PREGNANCY: LIKELY SAFE
when used orally in amounts commonly found in foods.

PREGNANCY: POSSIBLY UNSAFE
when used orally in medicinal amounts. Cardamom is thought to have abortifacient and emmenagogue effects (19,39884). Avoid using amounts greater than those used in food.

LACTATION: LIKELY SAFE
when used orally in amounts commonly found in foods. There is insufficient reliable information available about the safety of cardamom when used in medicinal amounts. Avoid using amounts greater than those used in food.

(Read more about CARDAMOM)

There is insufficient reliable information available about the safety of chaga.

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.

(Read more about CHAGA)

LIKELY SAFE ...when used orally in amounts commonly found in foods. Clove, clove oil, and eugenol have Generally Recognized As Safe (GRAS) status for use in foods in the US (4912).

POSSIBLY SAFE ...when clove oil is applied topically (272). A clove oil 1% cream has been applied to the anus with apparent safety for up to 6 weeks (43487). A liposome-based product containing clove oil 45% has been applied to the palms with apparent safety for up to 2 weeks (100596).

LIKELY UNSAFE ...when clove smoke is inhaled. Smoking clove cigarettes can cause respiratory injury (17,43599). ...when clove oil is injected intravenously. This can cause pulmonary edema, hypoxemia, and acute dyspnea (16384). There is insufficient reliable information available about the safety of using clove orally in medicinal amounts.

CHILDREN: LIKELY UNSAFE
when clove oil is taken orally. Ingesting 5-10 mL of undiluted clove oil has been linked to reports of coagulopathy, liver damage, and other serious side effects in infants and children up to 3 years of age (6,17,43385,43395,43419,43457,43652).

PREGNANCY AND LACTATION: LIKELY SAFE
when used orally in amounts found in foods (4912). Clove, clove oil, and eugenol have Generally Recognized As Safe (GRAS) status for use in foods in the US (4912). There is insufficient reliable information available about the safety of using clove in medicinal amounts during pregnancy and lactation; avoid using.

(Read more about CLOVE)

LIKELY SAFE ...when used orally and appropriately (13161,14306,14307,14308,15655,15752,17187,92271,92274,103247)(103250,108898). However, cocoa naturally contains caffeine, and caffeine may be unsafe when used orally in doses of more than 400 mg daily (11733,98806). While most cocoa products contain only small amounts of caffeine (about 2-35 mg per serving) (2708,3900), one cup of unsweetened, dry cocoa powder can contain up to 198 mg of caffeine (100515). To be on the safe side, cocoa should be used in amounts that provide less than 400 mg of caffeine daily. Keep in mind that only the amount of ADDED caffeine must be stated on product labels. The amount of caffeine naturally found in ingredients such as cocoa does not need to be provided. This can make it difficult to determine the total amount of caffeine in a given product. Cocoa and dark chocolate products worldwide also contain heavy metals such as lead and cadmium. In the US, one ounce (approximately 28 grams) of most commercially available dark chocolate products tested contained levels of lead and/or cadmium above the maximum allowable dose level for California, with cadmium levels generally increasing with the percentage of cocoa (109847,109848,109849). Advise patients to consume cocoa in moderation. ...when used topically. Cocoa butter is used extensively as a base for ointments and suppositories and is generally considered safe (11).

CHILDREN: POSSIBLY UNSAFE
when dark chocolate is used orally. Cocoa and dark chocolate products worldwide contain heavy metals such as lead and cadmium. In the US, one ounce (approximately 28 grams) of most commercially available dark chocolate products tested contained levels of lead and/or cadmium above the maximum allowable dose level for California, with cadmium levels generally increasing with the percentage of cocoa (109847,109848,109849). Children are at increased risk of adverse effects from intake of lead and/or cadmium. There is insufficient reliable information available about the safety of other chocolate-based products that typically contain smaller quantities of cocoa.

PREGNANCY: POSSIBLY SAFE
when used orally in moderate amounts. However, due to the caffeine content of cocoa preparations, intake should be closely monitored during pregnancy to ensure moderate consumption. Fetal blood concentrations of caffeine approximate maternal concentrations (4260). Some research has found that intrauterine exposure to even modest amounts of caffeine, based on maternal blood levels during the first trimester, is associated with a shorter stature in children ages 4-8 years (109846). While many cocoa products contain only small amounts of caffeine (about 2-35 mg per serving) (2708,3900), unsweetened, dry cocoa powder can contain up to 198 mg of caffeine per cup (100515). According to a review by Health Canada, and a subsequent large meta-analysis conducted in the US, doses of up to 300 mg daily can be consumed during pregnancy without an increased risk of spontaneous abortion, still birth, preterm birth, fetal growth retardation, or congenital malformations (11733,98806). To be on the safe side, cocoa should be used in amounts that provide less than 300 mg of caffeine daily. Keep in mind that only the amount of ADDED caffeine must be stated on product labels. The amount of caffeine found in ingredients such as cocoa, which naturally contains caffeine, does not need to be provided. This can make it difficult to determine the total amount of caffeine in a given product.

PREGNANCY: POSSIBLY UNSAFE
when used orally in large amounts. Caffeine found in cocoa crosses the placenta producing fetal blood concentrations similar to maternal levels (4260). Consumption of caffeine in amounts over 300 mg daily is associated with a significantly increased risk of miscarriage in some studies (16014,98806). Additionally, high intake of caffeine during pregnancy have been associated with premature delivery, low birth weight, and loss of the fetus (6). While many cocoa products contain only small amounts of caffeine (about 2-35 mg per serving) (2708,3900), unsweetened, dry cocoa powder can contain up to 198 mg of caffeine per cup (100515). To be on the safe side, cocoa should be used in amounts that provide less than 300 mg of caffeine daily (2708). Keep in mind that only the amount of ADDED caffeine must be stated on product labels. The amount of caffeine found in ingredients such as cocoa, which naturally contains caffeine, does not need to be provided. This can make it difficult to determine the total amount of caffeine in a given product. Cocoa and dark chocolate products worldwide also contain heavy metals such as lead and cadmium. In the US, one ounce (approximately 28 grams) of most commercially available dark chocolate products tested contained levels of lead and/or cadmium above the maximum allowable dose level for California, with cadmium levels generally increasing with the percentage of cocoa (109847,109848,109849). Large doses or excessive intake of cocoa should be avoided during pregnancy.

LACTATION: POSSIBLY SAFE
when used in moderate amounts or in amounts commonly found in foods. Due to the caffeine content of cocoa preparations, intake should be closely monitored while breastfeeding. During lactation, breast milk concentrations of caffeine are thought to be approximately 50% of serum concentrations. Moderate consumption of cocoa would likely result in very small amounts of caffeine exposure to a nursing infant (6). Keep in mind that only the amount of ADDED caffeine must be stated on product labels. The amount of caffeine found in ingredients such as cocoa, which naturally contains caffeine, does not need to be provided. This can make it difficult to determine the total amount of caffeine in a given product.

LACTATION: POSSIBLY UNSAFE
when used orally in large amounts. Consumption of excess chocolate (16 oz per day) may cause irritability and increased bowel activity in the infant (6026). Cocoa and dark chocolate products worldwide also contain heavy metals such as lead and cadmium. In the US, one ounce (approximately 28 grams) of most commercially available dark chocolate products tested contained levels of lead and/or cadmium above the maximum allowable dose level for California, with cadmium levels generally increasing with the percentage of cocoa (109847,109848,109849). Large doses or excessive intake of cocoa should be avoided during lactation.

(Read more about COCOA)

POSSIBLY SAFE ...when used orally and appropriately. Cordyceps has been used with apparent safety in doses of 3-6 grams daily for up to 1 year (12,12095,92828,95905,105076,111903).

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.

(Read more about CORDYCEPS)

LIKELY SAFE ...when used orally and appropriately. Ginger has been safely used in multiple clinical trials (721,722,723,5343,7048,7084,7085,7400,7623,11346)(12472,13080,13237,13244,17369,17928,17929,89889,89890,89894)(89895,89898,89899,90102,96252,96253,96259,96260,96669) (101760,101761,101762,103359,107903).

POSSIBLY SAFE ...when used topically and appropriately, short-term (89893,89897).

CHILDREN: LIKELY SAFE
when consumed in the amounts typically found in foods.

CHILDREN: POSSIBLY SAFE
when used orally and appropriately, short-term. Ginger powder has been used with apparent safety at a dose of up to 750 mg daily for 4 days in girls aged 14-18 years (96255).

PREGNANCY: LIKELY SAFE
when consumed in the amounts typically found in foods. Ginger is considered a first-line nonpharmacological treatment option for nausea in pregnancy by the American College of Obstetrics and Gynecology (ACOG) (111601). However, it should not be used long-term or without medical supervision and close monitoring.

PREGNANCY: POSSIBLY SAFE
when used for medicinal purposes. Despite some early reports of adverse effects (721,7083) and one observational study suggesting that taking dried ginger and other herbal supplements during the first 20 weeks of pregnancy marginally increased the chance of stillbirth (96254), most research shows that ginger is unlikely to cause harm to the baby. The risk for major malformations in infants of parents who took ginger when pregnant does not appear to be higher than the baseline rate of 1% to 3% (721,1922,5343,11346,13071,13080,96254). Also, other research suggests that ginger intake during various trimesters does not significantly affect the risk of spontaneous abortion, congenital malformations, stillbirth, perinatal death, preterm birth, low birth weight, or low Apgar scores (18211,90103). Ginger use has been associated with an increase in non-severe vaginal bleeding, including spotting, after week 17 of pregnancy (18211).

LACTATION: LIKELY SAFE
when consumed in the amounts typically found in foods. There is insufficient reliable information available about the safety of ginger when used for medicinal purposes; avoid amounts greater than those found in foods.

(Read more about GINGER)

LIKELY SAFE ...when used orally and appropriately. For people age 14 and older with adequate iron stores, iron supplements are safe when used in doses below the tolerable upper intake level (UL) of 45 mg per day of elemental iron. The UL is not meant to apply to those who receive iron under medical supervision (7135,96621). To treat iron deficiency, most people can safely take up to 300 mg elemental iron per day (15). ...when used intravenously and appropriately. Ferric carboxymaltose 200 mg and iron sucrose 200 mg have been given intravenously for up to 10 doses with no reported serious adverse effects (91179). A meta-analysis of clinical studies of hemodialysis patients shows that administering high-dose intravenous (IV) iron does not increase the risk of hospitalization, infection, cardiovascular events, or death when compared with low-dose IV iron, oral iron, or no iron treatment (102861). A more recent meta-analysis of clinical studies of all patient populations shows that administering IV iron does not increase the risk of hospital length of stay or mortality, although the risk of infection is increased by 16% when compared with oral iron or no iron (110186). Despite these findings, there are rare reports of hypophosphatemia and/or osteomalacia (112603,112608,112609,112610).

LIKELY UNSAFE ...when used orally in excessive doses. Doses of 30 mg/kg are associated with acute toxicity. Long-term use of high doses of iron can cause hemosiderosis and multiple organ damage. The estimated lethal dose of iron is 180-300 mg/kg; however, doses as low as 60 mg/kg have also been lethal (15).

CHILDREN: LIKELY SAFE
when used orally and appropriately (7135,91183,112601).

CHILDREN: LIKELY UNSAFE
when used orally in excessive amounts. Tell patients who are not iron-deficient not to use doses above the tolerable upper intake level (UL) of 40 mg per day of elemental iron for infants and children. Higher doses frequently cause gastrointestinal side effects such as constipation and nausea (7135,20097). Iron is the most common cause of pediatric poisoning deaths. Doses as low as 60 mg/kg can be fatal (15).

PREGNANCY AND LACTATION: LIKELY SAFE
when used orally and appropriately. Iron is safe during pregnancy and breast-feeding in patients with adequate iron stores when used in doses below the tolerable upper intake level (UL) of 45 mg daily of elemental iron (7135,96625,110180).

PREGNANCY AND LACTATION: LIKELY UNSAFE
when used orally in high doses. Tell patients who are not iron deficient to avoid exceeding the tolerable upper intake level (UL) of 45 mg daily of elemental iron. Higher doses frequently cause gastrointestinal side effects such as nausea and vomiting (7135) and might increase the risk of preterm labor (100969). High hemoglobin concentrations at the time of delivery are associated with adverse pregnancy outcomes (7135,20109).

(Read more about IRON)

LIKELY SAFE ...when used orally and appropriately in amounts commonly found in foods. Nutmeg is commonly used as a spice. Nutmeg and nutmeg oil have Generally Recognized as Safe (GRAS) status in the US (4912). There is insufficient reliable information available about the safety of nutmeg when used orally in larger doses, up to 120 mg daily. These doses have not been adequately evaluated in clinical research. However, doses at or above 120 mg daily have been associated with serious adverse effects (19292).

POSSIBLY UNSAFE ...when used orally in doses of 120 mg or greater. Chronic use of nutmeg in these doses has been associated with psychotic episodes and hallucinations (19292,19296,19487). Acute intoxication from nutmeg has been described in several case reports in which subjects ingested a single dose of 5-80 grams (2563,19297,19300,19491,111750). Symptoms of toxicity ranged from nausea, dry mouth, and dizziness to palpitations, agitation, and hallucinations (2563,3494,19293,19294,19295,19297,19298,19299,19489,19490)(19491,103373,111750). Two deaths involving nutmeg intoxication have also been reported (19300,112016) . Symptoms generally start 0.5-8 hours after ingestion and last up to 24-48 hours (19298,19488,19491,103372,103373). There is insufficient reliable information available about the safety of nutmeg when used topically.

PREGNANCY: LIKELY SAFE
when used orally and appropriately in amounts commonly found in foods.

PREGNANCY: POSSIBLY UNSAFE
when used orally in medicinal amounts. Nutmeg might have abortifacient activity, and its safrole content might be mutagenic (12).

LACTATION: LIKELY SAFE
when used orally and appropriately in amounts commonly found in foods. There is insufficient reliable information available about the safety of nutmeg when used in larger, medicinal amounts during lactation; avoid using.

(Read more about NUTMEG)

LIKELY SAFE ...when used orally in doses up to 100 mEq total potassium daily, not to exceed 200 mEq in a 24-hour period (95010,107989). Oral potassium chloride and potassium citrate are FDA-approved prescription products (95010,107989). Larger doses increase the risk of hyperkalemia (15). ...when administered intravenously (IV) at appropriate infusion rates (95011). Parenteral potassium is an FDA-approved prescription product (15,95011). A tolerable upper intake level (UL) for potassium has not been established; however, potassium levels should be monitored in individuals at increased risk for hyperkalemia, such as those with kidney disease, heart failure, and adrenal insufficiency (100310,107966).

CHILDREN: LIKELY SAFE
when used orally and appropriately in dietary amounts. A tolerable upper intake level (UL) has not been established for healthy individuals (6243,100310).

PREGNANCY AND LACTATION: LIKELY SAFE
when used orally in dietary amounts of 40-80 mEq daily (15). A tolerable upper intake level (UL) has not been established for healthy individuals (100310).

(Read more about POTASSIUM)

POSSIBLY SAFE ...when an extract of reishi mushroom is used orally and appropriately for up to one year (12,5485,70767,70774,70786,70799,70800,70801,70802). ...when whole powdered reishi mushroom is used orally and appropriately for up to 16 weeks (70776,70799,70800,70801,91433,91435,91436,91437,108309).

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using

(Read more about REISHI MUSHROOM)

LIKELY SAFE ...when used orally and appropriately. Sodium is safe in amounts that do not exceed the Chronic Disease Risk Reduction (CDRR) intake level of 2.3 grams daily (100310). Higher doses can be safely used therapeutically with appropriate medical monitoring (26226,26227).

POSSIBLY UNSAFE ...when used orally in high doses. Tell patients to avoid exceeding the CDRR intake level of 2.3 grams daily (100310). Higher intake can cause hypertension and increase the risk of cardiovascular disease (26229,98176,98177,98178,98181,98183,98184,100310,109395,109396,109398,109399). There is insufficient reliable information available about the safety of sodium when used topically.

CHILDREN: LIKELY SAFE
when used orally and appropriately (26229,100310). Sodium is safe in amounts that do not exceed the CDRR intake level of 1.2 grams daily for children 1 to 3 years, 1.5 grams daily for children 4 to 8 years, 1.8 grams daily for children 9 to 13 years, and 2.3 grams daily for adolescents (100310).

CHILDREN: POSSIBLY UNSAFE
when used orally in high doses. Tell patients to avoid prolonged use of doses exceeding the CDRR intake level of 1.2 grams daily for children 1 to 3 years, 1.5 grams daily for children 4 to 8 years, 1.8 grams daily for children 9 to 13 years, and 2.3 grams daily for adolescents (100310). Higher intake can cause hypertension (26229).

PREGNANCY AND LACTATION: LIKELY SAFE
when used orally and appropriately. Sodium is safe in amounts that do not exceed the CDRR intake level of 2.3 grams daily (100310).

PREGNANCY AND LACTATION: POSSIBLY UNSAFE
when used orally in higher doses. Higher intake can cause hypertension (100310). Also, both the highest and the lowest pre-pregnancy sodium quintile intakes are associated with an increased risk of hypertensive disorders of pregnancy, including gestational hypertension and pre-eclampsia, and the delivery of small for gestational age (SGA) infants when compared to the middle intake quintile (106264).

(Read more about SODIUM)

LIKELY SAFE ...when used orally and appropriately, short-term. Turmeric products providing up to 8 grams of curcumin have been safely used for up to 2 months (10453,11144,11150,17953,79085,89720,89721,89724,89728,101347)(81036,101349,107110,107116,107117,107118,107121,109278,109283). Turmeric in doses up to 3 grams daily has been used with apparent safety for up to 3 months (102350,104146,104148,113357). ...when used topically and appropriately (11148).

POSSIBLY SAFE ...when used as an enema, short-term. Turmeric extract in water has been used as a daily enema for up to 8 weeks (89729). ...when used topically as a mouthwash, short-term. A mouthwash containing 0.05% turmeric extract and 0.05% eugenol has been used safely twice daily for up to 21 days (89723).

PREGNANCY: LIKELY SAFE
when used orally in amounts commonly found in food.

PREGNANCY: LIKELY UNSAFE
when used orally in medicinal amounts; turmeric might stimulate the uterus and increase menstrual flow (12).

LACTATION: LIKELY SAFE
when used orally in amounts commonly found in food. There is insufficient reliable information available about the safety of using turmeric in medicinal amounts during lactation.

(Read more about TURMERIC)

AMOXICILLIN (Amoxil, Trimox) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase the effects and side effects of amoxicillin.  Details Animal research shows that taking piperine, a constituent of black pepper, with amoxicillin increases plasma levels of amoxicillin (29269). This has not been reported in humans.

ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase the risk of bleeding when taken with antiplatelet or anticoagulant drugs.  Details In vitro research shows that piperine, a constituent of black pepper, seems to inhibit platelet aggregation (29206). This has not been reported in humans.

ANTIDIABETES DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase the risk of hypoglycemia when taken with antidiabetes drugs.  Details Animal research shows that piperine, a constituent of black pepper, can reduce blood glucose levels (29225). Monitor blood glucose levels closely. Dose adjustments might be necessary.

ATORVASTATIN (Lipitor) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase blood levels of atorvastatin.  Details Animal research shows that taking piperine, a constituent of black pepper, 35 mg/kg can increase the maximum serum concentration of atorvastatin three-fold (104188). This has not been reported in humans.

CARBAMAZEPINE (Tegretol) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, black pepper might increase blood levels of carbamazepine, potentially increasing the effects and side effects of carbamazepine.  Details One clinical study in patients taking carbamazepine 300 mg or 500 mg twice daily shows that taking a single 20 mg dose of purified piperine, a constituent of black pepper, increases carbamazepine levels. Piperine may increase carbamazepine absorption by increasing blood flow to the GI tract, increasing the surface area of the small intestine, or inhibiting cytochrome P450 3A4 (CYP3A4) in the gut wall. Absorption was significantly increased by 7-10 mcg/mL/hour. The time to eliminate carbamazepine was also increased by 4-8 hours. Although carbamazepine levels were increased, this did not appear to increase side effects (16833). In vitro research also shows that piperine can increase carbamazepine levels by 11% in a time-dependent manner (103819).

CYCLOSPORINE (Neoral, Sandimmune) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase the effects and side effects of cyclosporine.  Details In vitro research shows that piperine, a constituent of black pepper, increases the bioavailability of cyclosporine (29282). This has not been reported in humans.

CYTOCHROME P450 1A1 (CYP1A1) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase levels of drugs metabolized by CYP1A1.  Details In vitro research suggests that piperine, a constituent of black pepper, inhibits CYP1A1 (29213). This has not been reported in humans.

CYTOCHROME P450 2B1 (CYP2B1) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase levels of drugs metabolized by CYP2B1.  Details In vitro research suggests that piperine, a constituent of black pepper, inhibits CYP2B1 (29332). This has not been reported in humans.

CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase levels of drugs metabolized by CYP2D6.  Details In vitro research suggests that some constituents of black pepper inhibit CYP2D6 (29207,29212,38375). This has not been reported in humans.

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase levels of drugs metabolized by CYP3A4.  Details In vitro research shows that piperine, a constituent of black pepper, as well as the pepper fruit seem to inhibit CYP3A4 (14375,29212). This has not been reported in humans.

LITHIUM Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D Theoretically, black pepper might increase blood levels of lithium due to its diuretic effects. The dose of lithium might need to be reduced.  Details Black pepper is thought to have diuretic properties (11).

NEVIRAPINE (Viramune) Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = D Black pepper might increase blood levels of nevirapine.  Details Clinical research shows that piperine, a constituent of black pepper, increases the plasma concentration of nevirapine. However, no adverse effects were observed in this study (29209).

P-GLYCOPROTEIN SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase levels of P-glycoprotein substrates.  Details In vitro research shows that piperine, a constituent of black pepper, seems to inhibit P-glycoprotein (14375,29281,29283).

PENTOBARBITAL (Nembutal) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase the sedative effects of pentobarbital.  Details Animal research shows that piperine, a constituent of black pepper, increases pentobarbital-induced sleeping time (29214).

PHENYTOIN (Dilantin) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = B Black pepper might increase blood levels of phenytoin.  Details Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption, slow elimination, and increase levels of phenytoin (537,14442). Taking a single dose of black pepper 1 gram along with phenytoin seems to double the serum concentration of phenytoin (14375). Consuming a soup with black pepper providing piperine 44 mg/200 mL of soup along with phenytoin also seems to increase phenytoin levels when compared with consuming the same soup without black pepper (14442).

PROPRANOLOL (Inderal) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Black pepper might increase blood levels of propranolol.  Details Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption and slow elimination of propranolol (538).

RIFAMPIN (Rifadin) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = B Black pepper might increase blood levels of rifampin.  Details Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption and serum levels of rifampin (14375,29284).

THEOPHYLLINE Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Black pepper might increase blood levels of theophylline.  Details Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption and slow elimination of theophylline (538).

(Read more about BLACK PEPPER)

ADENOSINE (Adenocard) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, black tea might decrease the vasodilatory effects of adenosine and interfere with its use prior to stress testing.  Details Black tea contains caffeine. Caffeine is a competitive inhibitor of adenosine at the cellular level (38172). However, caffeine does not seem to affect supplemental adenosine because high interstitial levels of adenosine overcome the antagonistic effects of caffeine (11771). It is recommended that methylxanthines such as caffeine, as well as methylxanthine-containing products, be stopped 24 hours prior to pharmacological stress tests (11770). However, methylxanthines appear more likely to interfere with dipyridamole (Persantine) than adenosine-induced stress testing (11771).

ALCOHOL (Ethanol) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, alcohol might increase the levels and adverse effects of caffeine.  Details Black tea contains caffeine. Concomitant use of alcohol and caffeine can increase caffeine serum concentrations and the risk of caffeine adverse effects. Alcohol reduces caffeine metabolism (6370,24693).

ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, black tea may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.  Details Black tea contains caffeine. Caffeine is reported to have antiplatelet activity (8028,8029,36425). Theoretically, the caffeine in black tea might increase the risk of bleeding when used concomitantly with antiplatelet drugs. However, this interaction has not been reported in humans.

ANTIDIABETES DRUGS Interaction Rating = Minor Be watchful with this combination. Severity = Moderate •  Occurrence = Unlikely •  Level of Evidence = B Theoretically, taking black tea with antidiabetes drugs might interfere with blood glucose control.  Details Black tea contains caffeine. Reports claim that caffeine might increase or decrease blood sugar levels (6024,8646). Also, some evidence in healthy individuals suggests that drinking black tea reduces blood sugar (92403).

BETA-ADRENERGIC AGONISTS Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = D Theoretically, concomitant use of large amounts of black tea might increase cardiac inotropic effects of beta-agonists.  Details Black tea contains caffeine. Caffeine can increase cardiac inotropic effects of beta-agonists (15).

CARBAMAZEPINE (Tegretol) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = B Theoretically, black tea might reduce the effects of carbamazepine and increase the risk for convulsion.  Details Black tea contains caffeine. Animal research suggests that caffeine can lower the anticonvulsant effects of carbamazepine and can induce seizures when taken in doses above 400 mg/kg (23559,23561). Human research has shown that taking caffeine 300 mg in three divided doses along with carbamazepine 200 mg reduces the bioavailability of carbamazepine by 32% and prolongs the plasma half-life of carbamazepine 2-fold in healthy individuals (23562).

CIMETIDINE (Tagamet) Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Likely •  Level of Evidence = B Theoretically, concomitant use might increase the effects and adverse effects of caffeine in black tea.  Details Black tea contains caffeine. Cimetidine can reduces caffeine clearance by 31% to 42% (11736,24700).

CLOZAPINE (Clozaril) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = B Theoretically, black tea might increase the levels and adverse effects of clozapine and acutely exacerbate psychotic symptoms.  Details Concomitant administration of black tea and clozapine might theoretically cause acute exacerbation of psychotic symptoms due to the caffeine in black tea. Caffeine can increase the effects and toxicity of clozapine. Caffeine doses of 400-1000 mg daily inhibit clozapine metabolism (5051). Clozapine is metabolized by cytochrome P450 1A2 (CYP1A2). Researchers speculate that caffeine might inhibit CYP1A2. However, there is no reliable evidence that caffeine affects CYP1A2. There is also speculation that genetic factors might make some patients be more sensitive to the interaction between clozapine and caffeine (13741).

CONTRACEPTIVE DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = B Theoretically, concomitant use might increase the effects and adverse effects of caffeine found in black tea.  Details Black tea contains caffeine. Oral contraceptive drugs can decrease caffeine clearance by 40% to 65% (2714,11737).

CYTOCHROME P450 1A2 (CYP1A2) INHIBITORS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use might increase the levels and adverse effects of caffeine.  Details Black tea contains caffeine. Caffeine is metabolized by CYP1A2 (3941,5051,11741,23557,23573,23580,24958,24959,24960,24962), (24964,24965,24967,24968,24969,24971,38081,48603). Theoretically, drugs that inhibit CYP1A2 may decrease the clearance rate of caffeine from black tea and increase caffeine levels.

DIPYRIDAMOLE (Persantine) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Theoretically, black tea might decrease the vasodilatory effects of dipyridamole and interfere with its use prior to stress testing.  Details Black tea contains caffeine. Caffeine is a methylxanthine that may inhibit dipyridamole-induced vasodilation (11770,11772,24974,37985,53795). It is recommended that methylxanthines such as caffeine, as well as methylxanthine-containing products such as black tea, be stopped 24 hours prior to pharmacological stress tests (11770). Methylxanthines appear more likely to interfere with dipyridamole (Persantine) than adenosine-induced stress testing (11771).

DISULFIRAM (Antabuse) Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = B Theoretically, disulfiram might increase the risk of adverse effects from caffeine.  Details Black tea contains caffeine. In human research, disulfiram decreases the clearance and increases the half-life of caffeine (11840).

DIURETIC DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, using black tea with diuretic drugs might increase the risk of hypokalemia.  Details Black tea contains caffeine. Caffeine, especially in excessive amounts, can reduce potassium levels due to stimulation of the sodium-potassium pump (23579,37905,37953,38003,38034). Diuretics can also cause lower potassium levels.

EPHEDRINE Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = D Theoretically, concomitant use might increase the risk for simulant adverse effects.  Details Black tea contains caffeine. There is evidence that using ephedrine with caffeine might increase the risk of serious life-threatening or debilitating adverse effects such as hypertension, myocardial infarction, stroke, seizures, and death (6486,9740,10307). Tell patients to avoid taking caffeine with ephedrine and other stimulants.

ESTROGENS Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = B Theoretically, estrogens might increase the levels and adverse effects of caffeine.  Details Black tea contains caffeine. Estrogen inhibits caffeine metabolism (2714).

ETHOSUXIMIDE (Zarontin) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black tea might reduce the effects of ethosuximide and increase the risk for convulsions.  Details Black tea contains caffeine. Animal research suggests that caffeine 92.4 mg/kg can decrease the anticonvulsant activity of ethosuximide (23560). However, this effect has not been observed in humans.

FELBAMATE (Felbatol) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black tea might reduce the effects of felbamate and increase the risk for convulsions.  Details Black tea contains caffeine. Animal research suggests that a high dose of caffeine 161.7 mg/kg can decrease the anticonvulsant activity of felbamate (23563). However, this effect has not been observed in humans.

FLUCONAZOLE (Diflucan) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, fluconazole might increase the levels and adverse effects of caffeine.  Details Black tea contains caffeine. Fluconazole decreases caffeine clearance by approximately 25% (11022,24978).

FLURBIPROFEN (Ansaid, others) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Unlikely •  Level of Evidence = B Theoretically, black tea might decrease the metabolism of flurbiprofen.  Details In vitro research shows that black tea decreases the metabolism of flurbiprofen, a cytochrome P450 2C9 (CYP2C9) substrate, by about 10%. However, clinical research suggests that drinking black tea does not significantly affect flurbiprofen plasma levels, metabolism, or elimination (11094).

FLUTAMIDE (Eulexin) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black tea might increase the levels and adverse effects of flutamide.  Details Black tea contains caffeine. In vitro evidence suggests that caffeine can inhibit the metabolism of flutamide (23553). Theoretically, concomitant use of caffeine and flutamide might increase serum concentrations of flutamide and increase the risk of adverse effects.

FLUVOXAMINE (Luvox) Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = B Theoretically, fluvoxamine might increase the levels and adverse effects of caffeine.  Details Black tea contains caffeine. Fluvoxamine reduces caffeine metabolism (6370,38287).

LITHIUM Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D Theoretically, abrupt black tea withdrawal might increase the levels and adverse effects of lithium.  Details Black tea contains caffeine. Abrupt caffeine withdrawal can increase serum lithium levels (609). Two cases of lithium tremor that worsened with abrupt coffee withdrawal have been reported (610).

Metformin (Glucophage) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, metformin might increase the levels and adverse effects of caffeine.  Details Black tea contains caffeine. Animal research suggests that metformin can reduce caffeine metabolism (23571). Theoretically, concomitant use can increase caffeine serum concentrations and the risk of caffeine adverse effects.

METHOXSALEN (Oxsoralen) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, methoxsalen might increase the levels and adverse effects of caffeine.  Details Black tea contains caffeine. Methoxsalen can reduce caffeine metabolism (23572). Concomitant use can increase caffeine serum concentrations and the risk of caffeine adverse effects.

MEXILETINE (Mexitil) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, mexiletine might increase the levels and adverse effects of caffeine.  Details Black tea contains caffeine. Mexiletine can decrease caffeine elimination by 50% (1260,11741,24981).

MONOAMINE OXIDASE INHIBITORS (MAOIs) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use might increase the risk of a hypertensive crisis.  Details Black tea contains caffeine. Caffeine has been shown to inhibit monoamine oxidase (MAO) A and B in laboratory studies (37724,37877,37912,38108). Concomitant intake of large amounts of caffeine with MAOIs might precipitate a hypertensive crisis (15). In a case report, a patient that consumed 10-12 cups of caffeinate coffee and took the MAOI tranylcypromine presented with severe hypertension (91086). Hypertension was resolved after the patients switched to drinking decaffeinated coffee.

NICOTINE Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Theoretically, concomitant use might increase the risk of hypertension.  Details Black tea contains caffeine. Concomitant use of caffeine and nicotine has been shown to have additive cardiovascular effects, including increased heart rate and blood pressure. Blood pressure was increased by 10.8/12.4 mmHg when the agents were used concomitantly (36549).

ORGANIC ANION-TRANSPORTING POLYPEPTIDE SUBSTRATES (OATP) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black tea might reduce the absorption of organic anion-transporting polypeptide (OATP) substrates.  Details In vitro, black tea extract inhibits organic anion-transporting polypeptide (OATP)2B1. OATP2B1 is expressed in the small intestine and liver and is responsible for the uptake of drugs and other compounds. In an animal model, black tea extract was found to inhibit the absorption of rosuvastatin, a substrate of OATP2B1 (104584). However, this effect has not been reported in humans.

PENTOBARBITAL (Nembutal) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, black tea might decrease the effects of pentobarbital.  Details Black tea contains caffeine. Theoretically, caffeine might negate the hypnotic effects of pentobarbital (13742).

PHENOBARBITAL (Luminal) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, black tea might reduce the effects of phenobarbital and increase the risk for convulsions.  Details Black tea contains caffeine. Animal research suggests that caffeine can decrease the anticonvulsant activity of phenobarbital (23558,23559,23561). The exact mechanism of this interaction is unclear.

PHENOTHIAZINES Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, phenothiazines might increase the levels and adverse effects of caffeine. Also, black tea may bind to phenothiazines and reduce their absorption.  Details Black tea contains caffeine. Phenothiazines can reduce the metabolism of caffeine by inhibiting cytochrome P450 1A2 (CYP1A2) (23573,23574). Additionally, the tannins in black tea may bind to phenothiazines in the gastrointestinal tract and reduce their absorption (626,627).

PHENYLPROPANOLAMINE Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Theoretically, phenylpropanolamine might increase the risk of hypertension, as well as the levels and adverse effects of caffeine.  Details Black tea contains caffeine. Concomitant use of phenylpropanolamine and caffeine might cause an additive increase in blood pressure (11738). Phenylpropanolamine also seems to increase caffeine serum levels (13743).

PHENYTOIN (Dilantin) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black tea might reduce the effects of phenytoin and increase the risk for convulsions.  Details Black tea contains caffeine. Animal research suggests that caffeine can decrease the anticonvulsant activity of phenytoin (23559,23561). The effect does not seem to be related to the seizure threshold-lowering effects of caffeine. However, the exact mechanism of this interaction is unclear.

PIOGLITAZONE (Actos) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black tea might increase the levels and clinical effects of pioglitazone.  Details Black tea contains caffeine. Animal research suggests that caffeine can modestly increase the maximum concentration, area under the curve, and half-life of pioglitazone, and also reduce its clearance. This could increase the antidiabetic effects of pioglitazone (108812). However, the exact mechanism of this interaction is unclear.

QUINOLONE ANTIBIOTICS Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = B Theoretically, quinolone antibiotics might increase the levels and adverse effects of caffeine.  Details Black tea contains caffeine. Concomitant use of caffeine and quinolones can decrease caffeine clearance and increase effects and risk of adverse effects (606,607,608,23555,24695,24696,24697).

RILUZOLE (Rilutek) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use might increase the levels and adverse effects of both caffeine and riluzole.  Details Black tea contains caffeine. Caffeine and riluzole are both metabolized by cytochrome P450 1A2 (CYP1A2), and concomitant use might reduce metabolism of one or both agents (11739).

ROSUVASTATIN (Crestor) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use might decrease the levels and clinical effects of rosuvastatin.  Details In animals, taking black tea extract along with rosuvastatin reduces plasma levels of rosuvastatin by approximately 48%. In vitro, black tea extract was found to inhibit organic anion-transporting polypeptide (OATP)2B1, a protein expressed in the small intestine that is responsible for the uptake of rosuvastatin and other compounds (104584). This effect has not been reported in humans.

STIMULANT DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = C Theoretically, concomitant use might increase stimulant adverse effects.  Details Black tea contains caffeine. Due to the central nervous system (CNS) stimulant effects of caffeine, concomitant use with stimulant drugs can increase the risk of adverse effects (11832).

TERBINAFINE (Lamisil) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, terbinafine might increase the levels and adverse effects of caffeine.  Details Black tea contains caffeine. Terbinafine decreases the clearance of intravenous caffeine by 19% (11740).

THEOPHYLLINE Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = B Theoretically, black tea might increase the levels and adverse effects of theophylline.  Details Black tea contains caffeine, which can increase theophylline levels (11862,24984).

TIAGABINE (Gabitril) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, black tea might increase the levels and adverse effects of tiagabine.  Details Black tea contains caffeine. Animal research suggests that chronic caffeine administration can increase the serum concentrations of tiagabine. However, concomitant use does not seem to reduce the antiepileptic effects of tiagabine (23561).

TICLOPIDINE (Ticlid) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, ticlopidine might increase the levels and adverse effects of caffeine.  Details Black tea contains caffeine. In vitro evidence suggests that ticlopidine can inhibit caffeine metabolism (23557). However, this effect has not been reported in humans.

TRICYCLIC ANTIDEPRESSANTS (TCAs) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, TCAs might bind with black tea constituents when taken at the same time.  Details In vitro research suggests that the tannins in black tea might cause precipitation of TCAs (626,627). However, this effect has not been reported in humans.

VALPROATE Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black tea might reduce the effects of valproate and increase the risk for convulsions.  Details Black tea contains caffeine. Animal research suggests that caffeine can decrease the anticonvulsant activity of valproate (23558,23559,23561). However, the exact mechanism of this interaction is unclear.

VERAPAMIL (Calan, others) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use might increase the levels and adverse effects of caffeine.  Details Black tea contains caffeine. Verapamil increases plasma caffeine concentrations by 25% (11741).

WARFARIN (Coumadin) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Consuming large amounts of black tea might decrease the effects of warfarin.  Details In one case, a 67-year-old female who took warfarin and who regularly consumed large amounts of black tea had a stable international normalized ratio (INR) of 1.7 to 2.7. However, the INR increased to 5 when tea consumption was discontinued. It is thought that the vitamin K content of black tea may have reduced the effects of warfarin (16902). Monitor patients carefully who start or discontinue drinking black tea while taking warfarin.

(Read more about BLACK TEA)

(Read more about CARDAMOM)

ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, chaga may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.  Details In vitro and animal research suggests that chaga extract can inhibit platelet aggregation (26260). This effect has not been reported in humans.

ANTIDIABETES DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, taking chaga with antidiabetes drugs might increase the risk of hypoglycemia.  Details Animal research suggests that chaga might decrease blood glucose levels and increase insulin levels (26253,111924,111925,111927). This has not been reported in humans.

IMMUNOSUPPRESSANTS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, chaga might interfere with immunosuppressive therapy.  Details In vitro research suggests that certain constituents of chaga stimulate immune function (26263). This has not been reported in humans.

(Read more about CHAGA)

ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Minor Be watchful with this combination. Severity = Moderate •  Occurrence = Unlikely •  Level of Evidence = D Theoretically, clove oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.  Details Laboratory research suggests that eugenol, a constituent of clove, has antiplatelet activity (12889,43558,43650,43654). This interaction has not been reported in humans.

ANTIDIABETES DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use of clove extracts with antidiabetes drugs might increase the risk of hypoglycemia.  Details Clinical and laboratory research suggest that polyphenol extracts from clove flower buds might lower blood glucose levels (100595). Dosing adjustments for insulin or oral hypoglycemic agents may be necessary when taken with clove. Monitor blood glucose levels closely.

IBUPROFEN (Advil, others) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, topical application of clove oil with ibuprofen might increase the absorption and side effects of topical ibuprofen.  Details Laboratory research shows that topical application of clove oil increases the absorption of topical ibuprofen (98854). This interaction has not been reported in humans.

(Read more about CLOVE)

ACE INHIBITORS (ACEIs) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, taking cocoa with ACEIs might increase the risk of adverse effects.  Details Human research shows that dark chocolate can inhibit ACE (42112). Additionally, prolonged angioedema in an elderly patient on an ACE inhibitor was precipitated with intake of diabetic chocolate (42049).

ADENOSINE (Adenocard) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, cocoa might decrease the vasodilatory effects of adenosine and interfere with its use prior to stress testing.  Details Cocoa contains caffeine. Caffeine is a competitive inhibitor of adenosine at the cellular level. However, caffeine does not seem to affect supplemental adenosine because high interstitial levels of adenosine overcome the antagonistic effects of caffeine. It is recommended that methylxanthines and methylxanthine-containing products be stopped 24 hours prior to pharmacological stress tests. However, methylxanthines appear more likely to interfere with dipyridamole than adenosine-induced stress testing (11771).

ALCOHOL (Ethanol) Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = D Theoretically, concomitant use might increase levels and adverse effects of caffeine.  Details Cocoa contains caffeine. Alcohol reduces caffeine metabolism. Concomitant use of alcohol can increase caffeine serum concentrations and the risk of caffeine adverse effects (6370).

ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, cocoa may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.  Details Clinical research shows that intake of cocoa can inhibit platelet adhesion, aggregation, and activity (6085,17076,41928,41948,41957,41958,41995,42014,42070,42145)(111526) and increase aspirin-induced bleeding time (23800). For patients on dual antiplatelet therapy, cocoa may enhance the inhibitory effect of clopidogrel, but not aspirin, on platelet aggregation (111526).

ANTIHYPERTENSIVE DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, taking cocoa with antihypertensive drugs might increase the risk of hypotension.  Details Clinical research shows that cocoa can modestly decrease blood pressure in hypertensive and normotensive patients (13166,14306,15655,15752,17187,42059,42092,42107,42137,42143)(42169,103249,109446).

BETA-ADRENERGIC AGONISTS Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = D Theoretically, large amounts of cocoa might increase the cardiac inotropic effects of beta-agonists.  Details Cocoa contains caffeine. Theoretically, large amounts of caffeine might increase cardiac inotropic effects of beta-agonists (15). A case of atrial fibrillation associated with consumption of large quantities of chocolate in a patient with chronic albuterol inhalation abuse has also been reported (42075).

CIMETIDINE (Tagamet) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, concomitant use might increase the effects and adverse effects of caffeine in cocoa.  Details Cocoa contains caffeine. Cimetidine decreases caffeine clearance by 30% to 50% (15,506).

CONTRACEPTIVE DRUGS Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, concomitant use might increase the effects and adverse effects of caffeine found in cocoa.  Details Cocoa contains caffeine. Oral contraceptives decrease the rate of caffeine clearance by 40% to 65% (2714,11737).

CYTOCHROME P450 1A2 (CYP1A2) INHIBITORS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use might increase the levels and adverse effects of caffeine.  Details Cocoa contains caffeine. Caffeine is metabolized by cytochrome P450 1A2 (CYP1A2) (3941,5051,11741,23557,23573,23580,24958,24959,24960,24962), (24964,24965,24967,24968,24969,24971,38081,48603). Theoretically, drugs that inhibit CYP1A2 may decrease the clearance rate of caffeine from cocoa and increase caffeine levels.

DIPYRIDAMOLE (Persantine) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Theoretically, cocoa might decrease the vasodilatory effects of dipyridamole and interfere with its use prior to stress testing.  Details Cocoa contains caffeine. Caffeine may inhibit dipyridamole-induced vasodilation (11770,11772). It is recommended that methylxanthines and methylxanthine-containing products be stopped 24 hours prior to pharmacological stress tests (11770). Methylxanthines appear more likely to interfere with dipyridamole than adenosine-induced stress testing (11771).

DISULFIRAM (Antabuse) Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = B Theoretically, disulfiram might increase the risk of adverse effects from caffeine.  Details Cocoa contains caffeine. In human research, disulfiram decreases the rate of caffeine clearance (11840).

DIURETIC DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, using cocoa with diuretic drugs might increase the risk of hypokalemia.  Details Cocoa contains caffeine. In excessive amounts, caffeine can reduce potassium levels due to stimulation of the sodium-potassium pump (23579,37905,37953,38003,38034). Diuretics can also cause lower potassium levels.

EPHEDRINE Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use might increase the risk for stimulant adverse effects.  Details Cocoa contains caffeine. There is evidence that using ephedrine with caffeine might increase the risk of serious life-threatening or debilitating adverse effects such as hypertension, myocardial infarction, stroke, seizures, and death (1275,6486,10307).

ESTROGENS Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = B Theoretically, estrogens might increase the levels and adverse effects of caffeine.  Details Cocoa contains caffeine. Estrogen inhibits caffeine metabolism (2714).

FLUCONAZOLE (Diflucan) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, fluconazole might increase the levels and adverse effects of caffeine.  Details Cocoa contains caffeine. Fluconazole decreases caffeine clearance by approximately 25% (11022).

FLUTAMIDE (Eulexin) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, cocoa might increase the levels and adverse effects of flutamide.  Details Cocoa contains caffeine. In vitro evidence suggests that caffeine can inhibit the metabolism of flutamide (23553).

FLUVOXAMINE (Luvox) Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = D Theoretically, fluvoxamine might increase the levels and adverse effects of caffeine.  Details Cocoa contains caffeine. Fluvoxamine reduces caffeine metabolism (6370).

LITHIUM Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, abrupt cocoa withdrawal might increase the levels and adverse effects of lithium.  Details Cocoa contains caffeine. There are two case reports of lithium tremor that worsened upon abrupt coffee withdrawal (609,610).

METHOXSALEN (Oxsoralen) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, methoxsalen might increase the levels and adverse effects of caffeine.  Details Cocoa contains caffeine. Methoxsalen can reduce caffeine metabolism (23572).

METMORPHIN (Glucophage) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, metformin might increase the levels and adverse effects of caffeine.  Details Cocoa contains caffeine. Animal research suggests that metformin can reduce caffeine metabolism (23571).

MEXILETINE (Mexitil) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, mexiletine might increase the levels and adverse effects of caffeine.  Details Cocoa contains caffeine. Mexiletine can decrease caffeine elimination by 50% (1260,11741). Concomitant use might increase the effects and adverse effects of caffeine in cocoa.

MONOAMINE OXIDASE INHIBITORS (MAOIs) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use might increase the risk of a hypertensive crisis.  Details Cocoa contains caffeine. Large amounts of caffeine with MAOIs might precipitate a hypertensive crisis (15).

NICOTINE Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Theoretically, concomitant use might increase the risk of hypertension.  Details Cocoa contains caffeine. Concomitant use of caffeine and nicotine has been shown to have additive cardiovascular effects, including increased heart rate and blood pressure. Blood pressure was increased by 10.8/12.4 mmHg when the agents were used concomitantly (36549).

PENTOBARBITAL (Nembutal) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, cocoa might decrease the effects of pentobarbital.  Details Cocoa contains caffeine. Caffeine might negate the hypnotic effects of pentobarbital (13742).

PHENOBARBITAL (Luminal) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, cocoa might reduce the effects of phenobarbital and increase the risk for convulsions.  Details Cocoa contains caffeine. Animal research suggests that caffeine can decrease the anticonvulsant activity of phenobarbital (23558,23559,23561). The exact mechanism of this interaction is unclear.

PHENOTHIAZINES Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, phenothiazines might increase the levels and adverse effects of caffeine.  Details Cocoa contains caffeine. Phenothiazines can reduce the metabolism of caffeine by inhibiting cytochrome P450 1A2 (CYP1A2) (23573,23574).

PHENYLPROPANOLAMINE Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Theoretically, phenylpropanolamine might increase the risk of hypertension, as well as the levels and adverse effects of caffeine.  Details Cocoa contains caffeine. Concomitant use of phenylpropanolamine and caffeine might cause an additive increase in blood pressure (11738). Phenylpropanolamine also seems to increase caffeine serum levels (13743).

PHENYTOIN (Dilantin) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, cocoa might reduce the effects of phenytoin and increase the risk for convulsions.  Details Cocoa contains caffeine. Animal research suggests that caffeine can decrease the anticonvulsant activity of phenytoin (23559,23561). The effect does not seem to be related to the seizure threshold-lowering effects of caffeine. However, the exact mechanism of this interaction is unclear.

QUINOLONE ANTIBIOTICS Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = B Theoretically, quinolone antibiotics might increase the levels and adverse effects of caffeine.  Details Cocoa contains caffeine. Quinolones (also referred to as fluoroquinolones) decrease caffeine clearance (606,607,608).

RILUZOLE (Rilutek) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use might increase the levels and adverse effects of both caffeine and riluzole.  Details Cocoa contains caffeine. Caffeine and riluzole are both metabolized by cytochrome P450 1A2, and concomitant use might reduce metabolism of one or both agents (11739).

STIMULANT DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = C Theoretically, concomitant use might increase stimulant adverse effects.  Details Cocoa contains caffeine. Concomitant use might increase the risk of stimulant adverse effects (11832).

TERBINAFINE (Lamisil) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, terbinafine might increase the levels and adverse effects of caffeine.  Details Cocoa contains caffeine. Terbinafine decreases the rate of caffeine clearance (11740).

THEOPHYLLINE Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Theoretically, cocoa might increase the levels and adverse effects of theophylline.  Details Cocoa contains caffeine. Large amounts of caffeine might inhibit theophylline metabolism (11741). Caffeine decreases theophylline clearance 23% to 29% (506).

TIAGABINE (Gabitril) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, cocoa tea might increase the levels and adverse effects of tiagabine.  Details Cocoa contains caffeine. Animal research suggests that chronic caffeine administration can increase the serum concentrations of tiagabine. However, concomitant use does not seem to reduce the antiepileptic effects of tiagabine (23561).

TICLOPIDINE (Ticlid) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, ticlopidine might increase the levels and adverse effects of caffeine.  Details Cocoa contains caffeine. In vitro evidence suggests that ticlopidine can inhibit caffeine metabolism (23557). However, this effect has not been reported in humans.

VALPROATE Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, cocoa might reduce the effects of valproate and increase the risk for convulsions.  Details Cocoa contains caffeine. Animal research suggests that caffeine can decrease the anticonvulsant activity of valproate (23558,23559,23561,37882). However, the exact mechanism of this interaction is unclear.

VERAPAMIL (Calan, others) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, verapamil might increase the levels and adverse effects of caffeine.  Details Cocoa contains caffeine. Verapamil increases plasma caffeine concentrations by 25% (11741).

(Read more about COCOA)

ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, cordyceps may increase the risk of bleeding when used with antiplatelet or anticoagulant drugs.  Details In vitro and animal research suggests that cordyceps extract inhibits platelet aggregation and function (3429,46112). However, this interaction has not been reported in humans.

IMMUNOSUPPRESSANTS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, concurrent use of cordyceps might interfere with immunosuppressive therapy.  Details Animal and in vitro research suggests that cordyceps stimulates the immune system (3403,3404,3414,3431,3432). However, limited clinical research suggests that taking cordyceps may lower the necessary therapeutic dose of the immunosuppressant cyclosporine (92828), which suggests that cordyceps may have an immunosuppressive effect.

TESTOSTERONE Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, concurrent use of cordyceps and testosterone might have additive effects.  Details Animal research suggests that cordyceps can increase testosterone levels (46087). The clinical significance of this finding is unclear.

(Read more about CORDYCEPS)

ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = B Ginger may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs. However, research is conflicting.  Details Laboratory research suggests that ginger inhibits thromboxane synthetase and decreases platelet aggregation (7622,12634,20321,20322,20323,96257). However, this has not been demonstrated unequivocally in humans, with mixed results from clinical trials (96257). Theoretically, excessive amounts of ginger might increase the risk of bleeding when used with anticoagulant/antiplatelet drugs.

ANTIDIABETES DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, taking ginger with antidiabetes drugs might increase the risk of hypoglycemia.  Details Animal and human research suggests that ginger might increase insulin levels and/or decrease blood glucose levels (12636,20402,20403,20404,20405,89895,89896,107898).

CALCIUM CHANNEL BLOCKERS Interaction Rating = Minor Be watchful with this combination. Severity = Moderate •  Occurrence = Unlikely •  Level of Evidence = D Theoretically, taking ginger with calcium channel blockers might increase the risk of hypotension.  Details Some animal and in vitro research suggests that ginger has hypotensive and calcium channel-blocking effects (12633). Another animal study shows that concomitant administration of ginger and the calcium channel blocker amlodipine leads to greater reductions in blood pressure when compared with amlodipine alone (107901).

CYCLOSPORINE (Neoral, Sandimmune) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, when taken prior to cyclosporine, ginger might decrease cyclosporine levels.  Details In an animal model, ginger juice taken 2 hours prior to cyclosporine administration reduced the maximum concentration and area under the curve of cyclosporine by 51% and 40%, respectively. This effect was not observed when ginger juice and cyclosporine were administered at the same time (20401).

CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES Interaction Rating = Minor Be watchful with this combination. Severity = Insignificant •  Occurrence = Possible •  Level of Evidence = D Theoretically, ginger might increase the levels of CYP1A2 substrates.  Details In vitro research shows that ginger inhibits CYP1A2 activity (111544). However, this interaction has not been reported in humans.

CYTOCHROME P450 2B6 (CYP2B6) SUBSTRATES Interaction Rating = Minor Be watchful with this combination. Severity = Insignificant •  Occurrence = Possible •  Level of Evidence = D Theoretically, ginger might increase the levels of CYP2B6 substrates.  Details In vitro research shows that ginger inhibits CYP2B6 activity (111544). However, this interaction has not been reported in humans.

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES Interaction Rating = Minor Be watchful with this combination. Severity = Insignificant •  Occurrence = Possible •  Level of Evidence = D Theoretically, ginger might increase the levels of CYP2C9 substrates.  Details In vitro research shows that ginger inhibits CYP2C9 activity (111544). However, this interaction has not been reported in humans.

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Ginger might increase or decrease the levels of CYP3A4 substrates.  Details In vitro research and some case reports suggest that ginger inhibits CYP3A4 activity (111544,111644). Three case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking ginger and cancer medications that are CYP3A4 substrates (imatinib, dabrafenib, and crizotinib). However, the causality of this interaction is unclear due to the presence of multiple interacting drugs and routes of administration (111644). Conversely, other in vitro research suggests that ginger induces CYP3A4 activity, leading to reduced levels of CYP3A4 substrates (111404). However, this interaction has not been reported in humans.

LOSARTAN (Cozaar) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, ginger might increase levels of losartan and the risk of hypotension.  Details In animal research, ginger increased the levels and hypotensive effects of a single dose of losartan (102459). It is not clear if ginger alters the concentration or effects of losartan when taken continuously. Additionally, this interaction has not been shown in humans.

METRONIDAZOLE (Flagyl) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, ginger might increase levels of metronidazole.  Details In an animal model, ginger increased the absorption and plasma half-life of metronidazole. In addition, the elimination rate and clearance of metronidazole was significantly reduced (20350).

NIFEDIPINE (Procardia) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Ginger may have antiplatelet effects and increase the risk of bleeding if used with nifedipine.  Details Clinical research shows that combined treatment with ginger 1 gram plus nifedipine 10 mg significantly inhibits platelet aggregation when compared to nifedipine or ginger alone (20324).

P-GLYCOPROTEIN SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Ginger might increase the absorption and blood levels of P-glycoprotein (P-gp) substrates.  Details In vitro research and case reports suggest that ginger inhibits drug efflux by P-gp, potentially increasing absorption and serum levels of P-gp substrates (111544,111644). Two case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking ginger and cancer medications that are P-gp substrates (trametinib, crizotinib). However, the causality of this interaction is unclear due to the presence of multiple interacting drugs and routes of administration (111644).

PHENPROCOUMON (Marcoumar, others) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Ginger might increase the risk of bleeding with phenprocoumon.  Details Phenprocoumon, a warfarin-related anticoagulant, might increase the international normalized ratio (INR) when taken with ginger. There is one case report of a 76-year-old woman with a stable INR on phenprocoumon that increased to greater than 10 when she began consuming dried ginger and ginger tea (12880).

WARFARIN (Coumadin) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = B Ginger might increase the risk of bleeding with warfarin.  Details Laboratory research suggests that ginger might inhibit thromboxane synthetase and decrease platelet aggregation (7622,12634,20321,20322,20323). In one case report, ginger increased the INR when taken with phenprocoumon, which has similar pharmacological effects as warfarin (12880). In another case report, ginger increased the INR when taken with a combination of warfarin, hydrochlorothiazide, and acetaminophen (20349). A longitudinal analysis suggests that taking ginger increases the risk of bleeding in patients taking warfarin for at least 4 months (20348). However, research in healthy people suggests that ginger has no effect on INR, or the pharmacokinetics or pharmacodynamics of warfarin (12881,15176). Until more is known, monitor INRs closely in patients taking large amounts of ginger.

(Read more about GINGER)