Fermented Vitamin D3 2000 IU by New Chapter

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Serving Size 1 Tablet(s)

Ingredients	Amount Per Serving
Vitamin D3 (Cholecalciferol) (2000 IU, cholecalciferol from ferment media)	50 mcg
Turmeric (Curcuma longa ) (rhizome) (organic, from ferment media)	120 mg
organic Reishi (Ganoderma lucidum ) (mycelium and fruiting bodies) (Ling zhi)	20 mg

Other Ingredients

Gum Acacia, Brown Rice, Soy Flour, Saccharomyces cerevisiae Genus: Saccharomyces Species: cerevisiae, Lactobacillus acidophilus Genus: Lactobacillus Species: acidophilus, Bifidobacterium bifidum Genus: Bifidobacterium Species: bifidum, Lactobacillus rhamnosus Genus: Lactobacillus Species: rhamnosus, Papain, Bromelain, Silica, Tapioca Maltodextrin, Sunflower Lecithin, Palm Oil, Guar Gum PlantPart: gum

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Effectiveness view details

Below is general information about the effectiveness of the known ingredients contained in the product Fermented Vitamin D3 2000 IU. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.

REISHI MUSHROOM (organic Reishi)

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.

(Read more about REISHI MUSHROOM)

TURMERIC

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)

VITAMIN D (Vitamin D3)

EFFECTIVE

Familial hypophosphatemia. Oral vitamin D in combination with phosphate is effective for bone disorders in patients with familial hypophosphatemia. Details: Taking calcitriol or dihydrotachysterol orally in combination with phosphate supplements is effective for treating bone disorders in people with familial hypophosphatemia (11818).
Hypoparathyroidism. Oral vitamin D increases serum calcium concentrations in people with hypoparathyroidism or pseudohypoparathyroidism. Details: Vitamin D2 (ergocalciferol) is effective in high doses for increasing serum calcium concentrations in people with hypoparathyroidism or pseudohypoparathyroidism (11820). Also, taking vitamin D (form unspecified) or calcitriol postoperatively is effective for preventing hypocalcemia in people with hypoparathyroidism due to thyroidectomy (39045).
Osteomalacia. Oral vitamin D is effective for osteomalacia. Details: Oral calcifediol is effective for treating osteomalacia secondary to liver disease (hepatic osteodystrophy) and anticonvulsant-induced osteomalacia. Vitamin D2 (ergocalciferol) is effective for osteomalacia due to malabsorption syndromes, Fanconi syndrome, and corticosteroid-induced osteomalacia (11819,11821).
Renal osteodystrophy. Oral calcitriol prevents renal osteodystrophy in patients with chronic renal failure. Details: Taking calcitriol orally manages hypocalcemia and prevents renal osteodystrophy in patients with chronic renal failure undergoing dialysis (11823).
Rickets. Oral vitamin D prevents and treats rickets. Details: Vitamin D is effective for preventing and treating rickets, a consequence of vitamin D deficiency. Calcitriol should be used in patients with renal failure (11824). Clinical practice guidelines from the Endocrine Society conditionally recommend, based on low certainty of evidence, empiric vitamin D supplementation from vitamin D fortified foods, vitamin D supplements, or vitamin formulations that contain vitamin D to prevent nutritional rickets in children and adolescents aged 1 to 18 years. Empiric vitamin D supplementation is defined as supplementing with vitamin D above the Recommended Dietary Allowance without having tested serum vitamin D status (114502). A large clinical study in pregnant adults shows that taking vitamin D 28,000 IU weekly from the second trimester up to 6 months post-partum decreases the risk of biochemical rickets by about 84% in the offspring at 6-12 months of age when compared with placebo. However, taking vitamin D 4200, 16,800, or 28,000 IU weekly from the second trimester to delivery does not decrease the risk of rickets in the offspring when compared with placebo (114503).
Vitamin D deficiency. Oral vitamin D prevents and treats vitamin D deficiency. Details: Vitamin D is effective for preventing and treating vitamin D deficiency using a wide range of doses (7555,16888,16891,17476). Optimal blood levels of 25-hydroxyvitamin D for maintaining bone density is controversial; however, it is typically estimated that blood levels of 20-100 ng/mL are needed. Toxicity usually does not occur until levels exceed 150 ng/mL (17476,93945). Vitamin D also alleviates symptoms and syndromes associated with vitamin D deficiency. Administering vitamin D2 (ergocalciferol) intramuscularly or orally seems to help treat severe proximal myopathy associated with severe vitamin D deficiency. Several case reports suggest vitamin D therapy can provide prompt relief of muscle weakness and restore mobility (11923,84348,84687).

LIKELY EFFECTIVE

Corticosteroid-induced osteoporosis. Oral vitamin D prevents corticosteroid-induced osteopenia and osteoporosis. Details: Taking calcifediol, cholecalciferol, calcitriol, or alfacalcidol orally prevents corticosteroid-induced osteopenia and osteoporosis (7555,83933). Vitamin D3 metabolites, including calcitriol and alfacalcidol, seem to be more effective at preventing bone loss compared to cholecalciferol in these patients, although the vitamin D3 metabolites seem to be inferior to bisphosphonates (83955). Furthermore, taking activated vitamin D or other forms of vitamin D alone or along with calcium improves bone mineral density in people with corticosteroid-induced osteoporosis (38493,38581).
Osteoporosis. Adequate intake of vitamin D in conjunction with adequate calcium intake helps to prevent the progression of osteoporosis. It might also reduce the risk of a first fracture in some patients. However, its place in the prevention of secondary fracture is unclear. Details: The Bone Health and Osteoporosis Foundation (BHOF) recommends ensuring adequate vitamin D intake of 800-1000 IU daily along with adequate calcium intake for the prevention and treatment of osteoporosis in adults over 50 years of age. Supplementation can be used to augment dietary intake, with a target serum vitamin D level of 30 ng/mL (109425). In the US, foods that contain at least 120 IU vitamin D can be labelled with a health claim regarding the relationship between adequate vitamin D intake and a reduced risk for osteoporosis (97001). However, vitamin D supplementation is not recommended specifically for the primary prevention of osteoporosis. The US Preventive Task Force (USPSTF) states that the current evidence is insufficient to assess the balance of benefits and harms of vitamin D and calcium supplementation, alone or in combination, for the primary prevention of fractures in community dwelling adults without osteoporosis (95695). Clinical research shows that vitamin D3 (cholecalciferol) and calcium can decrease postmenopausal bone loss, improve bone density, help prevent osteoporosis, and decrease the risk of fractures (10932,12926,12930,12934,12952) (38973,39015,39026,84003,113584). According to one analysis, taking oral vitamin D3 700-800 IU daily with or without calcium reduces fracture risk in ambulatory and institutionalized elderly people (12933). Other analyses suggest that taking vitamin D as cholecalciferol, ergocalciferol, calcifediol, calcitriol, or alfacalcidol with or without calcium can reduce the risk of all fractures by up to 17%, nonvertebral fractures by up to 49%, and hip fractures by up to 30% in older adults. However, the incidence of vertebral fractures does not appear to be reduced with vitamin D supplementation (38942,38970,38973,39015,39026,84660,109053). Despite the majority of research showing benefit, some studies have not found a positive effect of vitamin D on fracture risk. Some analyses of clinical evidence, including patients with and without osteoporosis, show that taking vitamin D3 or vitamin D2 (ergocalciferol) alone does not reduce fracture risk, suggesting that adequate calcium intake is needed for any benefit to be realized (39015,84471). Also, some evidence suggests that vitamin D3 400 IU daily is not effective for the prevention of osteoporotic fractures in elderly nursing home residents (109053). Another clinical trial found that taking vitamin D3 800 IU daily with calcium 1200-1500 mg daily for 2 years does not increase bone mineral density (BMD) in Black postmenopausal adults. This may be due to the fact that Black females have a lower rate of bone remodeling, an increased calcium absorption efficiency, and reduced calcium excretion when compared with other ethnic groups; therefore, supplementation with vitamin D3 and calcium might not be as beneficial in these patients (16878). There is concern that vitamin D might not be effective for secondary prevention of fractures in elderly patients. A meta-analysis of clinical studies, including many studies cited above, and a large clinical study in elderly adults with a previous osteoporotic fracture show that taking vitamin D3 400-4000 IU daily or as a single dose up to 500,000 IU orally or injected annually with or without calcium 480-1200 mg daily for up to 5 years does not reduce the risk of hip, vertebral, or other fractures when compared with placebo or no treatment (13073,112486). Another study also shows that taking vitamin D3 800 IU and calcium 1000 mg daily does not prevent a second fracture in elderly patients, or prevent a first fracture in elderly patients with other risk factors such as low body weight (under 58 kg, 127.6 pounds), smoking, family history of hip fracture, or fair or poor self-reported health (12929). However, these studies have been criticized for failing to measure vitamin D levels and low adherence to study protocol (12931). Also, one of these studies did not use a placebo control (12929). Taking alfacalcidol orally seems to maintain BMD in prostatic carcinoma patients at risk for osteoporosis when treated with luteinizing hormone-releasing hormone analogue (LHRH-a). Alfacalcidol maintains, but does not increase, BMD in these patients (6360).
Psoriasis. Topical vitamin D or vitamin D analogues improve symptoms of psoriasis. This benefit is not seen with oral vitamin D. Details: Topical application of vitamin D in the form of calcitriol or other vitamin D analogues, such as calcipotriene, maxacalcitol, and paricalcitol, effectively treats plaque psoriasis in some patients, including those with chronic plaque psoriasis (11822,84325). Applying topical vitamin D or its analogues in combination with topical corticosteroids such as betamethasone seems to be more effective for treating plaque psoriasis than either agent used alone (22283,82572,84325,84536,84647). Despite evidence that patients with psoriasis have low baseline serum levels of vitamin D, taking oral vitamin D does not seem to prevent psoriasis, improve symptoms, or reduce the severity of psoriasis in general (11822,22283,82572,84325,84536,84647,98193,108426,112481,112482). An analysis of a large clinical study in older adults with mild psoriasis shows that taking a vitamin D3 (cholecalciferol) loading dose of 200,000 IU followed by vitamin D3 100,000 IU monthly for 1 year does not affect the severity or spread of psoriasis when compared with placebo (98193).

POSSIBLY EFFECTIVE

Allergic rhinitis (hay fever). Some research suggests that oral vitamin D reduces symptoms of allergic rhinitis in children and adults. It is unclear if oral vitamin D during pregnancy is beneficial for the prevention of allergic rhinitis in the child. Details: Preliminary clinical research in adults with allergic rhinitis and vitamin D deficiency shows that taking vitamin D 50,000 IU weekly for 8 weeks along with cetirizine improves overall symptom severity when compared with placebo and cetirizine. This improvement was not significant at 4 weeks, suggesting that symptom improvement might not occur until vitamin D has been adequately replenished (102120). Another moderate-sized clinical study conducted in China in adults with moderate to severe allergic rhinitis and vitamin D levels at the low end of the normal range shows that taking vitamin D 800 IU daily for 4 weeks along with mometasone nasal spray improves runny nose, itchy nose, and nasal congestion but does not reduce sneezing when compared with placebo and mometasone (112483). In children aged 5-15 years, 4 small- or moderate-sized clinical trials show that taking vitamin D 800 IU or 1000 IU daily for 1-6 months modestly reduces symptoms such as nasal congestion and rhinorrhea when compared with placebo or no supplementation (109728). It is unclear whether these children had vitamin D deficiency at baseline. Vitamin D supplementation during pregnancy has also been evaluated. A meta-analysis of three large clinical studies shows that prenatal vitamin D supplementation does not reduce the risk of the child developing allergic rhinitis when compared with low-dose vitamin D, placebo, or no intervention (108438).
Dental caries. Some research suggests that oral vitamin D reduces the risk of dental caries in children. Details: A meta-analysis of clinical research suggests that vitamin D3 (cholecalciferol) reduces the risk of cavities by 49%, and vitamin D2 (ergocalciferol) reduces the risk by 36% when compared with placebo in infants, children, and adolescents (84690). The validity of this finding is limited by the heterogeneity of the included trials. Also, clinical research shows an inverse correlation between cord blood vitamin D status and the number of decayed primary teeth in the infant at 12 months of age (104620). However, this same research shows that taking two oral prenatal doses of vitamin D2 50,000 IU during pregnancy does not prevent dental caries in the infant at 12 months of age or increase vitamin D levels in the cord blood (104620).
Heart failure. Limited research suggests that oral vitamin D reduces the risk of developing heart failure in some patients. However, vitamin D does not seem to improve outcomes in patients that have already developed heart failure. Details: Population research has found that vitamin D levels below 15 ng/mL are associated with increased risk of developing heart failure (16615). A meta-analysis of 17 trials, including the landmark Randomized Evaluation of Calcium Or vitamin D (RECORD) trial, shows that vitamin D reduces the risk of heart failure by 21% compared to not taking vitamin D in patients 60 years or older (91343). This finding is limited because none of the included trials were designed to determine effects on cardiovascular outcomes. In contrast, a secondary analysis of data from the Women's Health Initiative trial shows that taking vitamin D 400 IU with calcium 1000 mg daily is not associated with a reduced risk of heart failure in postmenopausal adults. However, a subgroup analysis of that trial shows that taking vitamin D plus calcium is associated with a 37% lower risk of developing heart failure in postmenopausal adults classified as low-risk for heart failure at baseline. It is speculated that high-risk patients might not benefit from vitamin D plus calcium due to negative interactions with medications used to manage cardiovascular risk factors in this group (97307). While vitamin D might be associated with a reduced risk of developing heart failure, most evidence suggests that vitamin D is not beneficial in patients already diagnosed with heart failure. In one small clinical trial, taking vitamin D3 50,000 IU weekly along with calcium citrate 800 mg daily for 6 months was not associated with an improvement in 6-minute walk test, timed get up and go test (TGUG), electrocardiographic variables, or health status when compared with placebo in adults with heart failure; mortality was not evaluated (97299,97300). In another clinical trial, taking vitamin D3 2000 IU daily did not decrease the risk of mortality when compared with placebo in New York Heart Association (NYHA) class 2 heart failure patients (16620).
Hyperparathyroidism-related bone loss. Limited evidence suggests that oral vitamin D is beneficial in patients with this condition. Details: Taking vitamin D3 (cholecalciferol) orally seems to help decrease secondary hyperparathyroidism and bone turnover in females. In one study, supplementation with vitamin D3 increased serum levels of 25-hydroxyvitamin D, reduced levels of parathyroid hormone, and decreased production of markers of bone turnover (3463).
Respiratory tract infections. Clinical research shows that oral vitamin D supplementation reduces the risk for respiratory tract infections in children but not in adults or older adults. Some clinical practice guidelines recommend vitamin D supplements or fortified foods for children to potentially lower the risk of respiratory tract infections. It is unclear if oral vitamin D is beneficial for the treatment of respiratory tract infections. Details: Prenatally, increased levels of vitamin D during pregnancy have been associated with a lower incidence of childhood respiratory tract infections (98197). However, two meta-analyses of small clinical studies and one meta-analysis of large clinical studies show no effect of prenatal vitamin D supplementation on the incidence of infant or childhood respiratory tract infections, including lower respiratory tract infections, when compared with control. Results related to risk of wheeze are conflicting (95910,95912,108438). In children, most research shows that vitamin D supplementation reduces the risk of respiratory infections. A meta-analysis of clinical trials in children aged 1-16 years shows that taking vitamin D decreases the odds of having a respiratory tract infection by about 29% when compared with control, although this study also identified a high likelihood of publication bias (105721). Daily or weekly vitamin D doses seem to be more beneficial than single bolus doses, although the largest meta-analysis failed to confirm this result (84689,93766,105721). One clinical study in preterm Black infants shows that taking vitamin D3 (cholecalciferol) 200 IU daily and then 400 IU daily until 6 months of age does not affect the rate of respiratory tract infections, but does reduce wheeze by 11%, when compared with a normal diet without vitamin D supplementation (98191). This study may not have been powered to detect a difference in respiratory tract infection between groups. Clinical practice guidelines from the Endocrine Society conditionally recommend, based on low certainty of evidence, empiric vitamin D supplementation from vitamin D fortified foods, vitamin D supplements, or vitamin formulations that contain vitamin D to potentially lower the risk of respiratory tract infections in children and adolescents aged 1 to 18 years. Empiric vitamin D supplementation is defined as supplementing with vitamin D above the Recommended Dietary Allowance without having tested serum vitamin D status (114502). In adults, vitamin D supplementation does not seem to reduce the risk of respiratory infections. Observational research in adults has found that low levels of vitamin D are associated with worsened respiratory tract infection complications, and even increased mortality from respiratory tract infections in older adults ages 50-75 years (103659). However, meta-analyses of prospective clinical trials in adults show that taking vitamin D supplements 300-4000 IU daily for 7 weeks to 5 years or taking vitamin D 30,000-100,000 IU monthly or 96,000-120,000 IU every 2 months for 1-5 years does not reduce the odds of developing a respiratory infection or severe respiratory complications, such as emergency department utilization, hospitalization, and death, when compared with placebo. These results were similar in subgroup analyses evaluating overall vitamin D dose and baseline vitamin D status (84689,105721,114506). The largest single clinical trial, conducted in adults at least 60 years of age, shows that taking vitamin D3 (cholecalciferol) 60,000 IU once monthly for up to 5 years reduces the duration of total and severe respiratory symptoms by approximately 0.5 days, but does not reduce the incidence of respiratory illness or hospitalization, when compared with placebo (105726,110825). A large meta-analysis of clinical studies in both children and adults shows that taking vitamin D does not reduce the risk of acute respiratory infections. While subgroup analyses revealed a reduced risk of acute respiratory infection in studies not exceeding 11 weeks' duration and with daily supplementation, these beneficial effects only persisted in studies considered to be of low quality (108435). Baseline vitamin D status was not assessed and the validity of these findings is limited by publication bias. Vitamin D has also been evaluated for the treatment of acute respiratory infections. A large meta-analysis of clinical studies in both children and adults shows that taking vitamin D improves outcomes (e.g., sputum conversion, survival rate, therapeutic success, need for intensive care admission) by a small, but not clinically relevant, amount. In subgroup analyses, these beneficial effects only persisted in studies considered to be of low quality (108436). The validity of these findings is limited by publication bias.
Tooth retention. Oral vitamin D with calcium seems to help with tooth retention in the elderly population. Details: A clinical trial in the elderly population shows that taking vitamin D3 (cholecalciferol) 700 IU daily along with calcium citrate malate 500 mg daily orally for 3 years reduces the risk of tooth loss by about 52% when compared with placebo (8816).

POSSIBLY INEFFECTIVE

Cardiovascular disease (CVD). Most research shows that taking vitamin D with or without calcium does not reduce the risk of CVD or CVD complications. There is some speculation that there might be modest benefit in the elderly, but more research is needed to confirm. Details: Population research has found that low vitamin D levels, especially those below 15 ng/mL, are associated with an increased risk of developing CVD (15630,16618,93944,113588). However, taking vitamin D supplements does not seem to prevent CVD. The majority of evidence from clinical research, population research, and meta-analyses shows that vitamin D supplementation, with or without calcium, does not reduce the risk of mortality, myocardial infarction, cardiac-related hospitalizations, or stroke when compared with placebo in patients with or without CVD risk factors (91343,97296,97305,97308,98902,98916,99762,109729,110811,110827)(112021,112022,113588). The most reliable evidence comes from two meta-analyses of mainly high-quality clinical research investigating the effect of supplementation with vitamin D alone or with calcium for at least 1 year. These analyses show that vitamin D does not reduce major adverse cardiovascular events, stroke, CVD mortality, or all-cause mortality, regardless of baseline vitamin D level, vitamin D dosage, sex, formulation, or concomitant calcium supplementation (99762,109729). One large clinical trial in individuals at increased CVD risk shows that taking vitamin D as cholecalciferol 60,000 IU monthly modestly INCREASES the risk of CVD- and presumed CVD-related mortality (110827). The effect of vitamin D supplementation in elderly adults on CVD outcomes has also been evaluated. In some research, taking vitamin D 700-1000 IU daily shows a trend towards lower CVD events and reduced risk of major adverse cardiovascular events in elderly patients (11931,98916,99762). However, another study in adults aged 70 years or older without a history of cardiovascular events and who are vitamin D replete at baseline shows that taking vitamin D 2000 IU daily for 3 years does not decrease the risk of coronary heart disease, heart failure, stroke, or hypertension when compared with placebo (113581). Larger, high-quality trials with prespecified primary outcomes are needed to determine whether or not vitamin D supplementation reduces CVD risk in elderly populations.
Critical illness (trauma). Taking vitamin D 540,000 IU as a single oral dose does not reduce death or hospital stay in critically ill patients. However, limited research suggests that taking a smaller dose of vitamin D long-term might have a modest benefit. Details: The most robust evidence to date shows that correcting vitamin D levels in critically ill patients with vitamin D deficiency does not reduce mortality rate or duration of hospital stay. A large, multicenter clinical study in critically ill patients with vitamin D deficiency shows that administering a single, enteral dose of vitamin D 540,000 IU does not reduce 90-day all-cause mortality, duration of hospital stay, ventilator-free days, or other clinical outcomes when compared with placebo (103656). A previous meta-analysis of clinical research showed that vitamin D supplementation administered for a duration of 7 days or up to 6 months reduces the risk of death by 30% in critically ill hospitalized patients (95913). However, included studies were of low methodological quality, had high heterogeneity, assessed patients with and without vitamin D deficiency, and used variable vitamin D dose regimens and administrations methods (95913,95914).
Fractures. Most evidence shows that oral vitamin D alone does NOT prevent factures in people who do not have osteoporosis. Some research shows that taking vitamin D with calcium prevents fractures; however, more research is needed to determine who is most likely to benefit. Details: Clinical research shows that taking vitamin D alone does not seem to prevent fractures in older adults. Most adults in these studies did not have osteoporosis, although osteoporosis status was unclear in some research (10140,12933,14282,38970,39015,84660,95822,97296,102145,104619)(109059,110827). However, several meta-analyses suggest that taking higher doses of vitamin D (about 800 IU daily) in combination with calcium might reduce overall fracture risk in older patients (38942,38970,39015,84660,102145,110809). One meta-analysis of clinical research in community- or long-term care-living males and females at least 65 years of age shows that taking vitamin D 800 IU daily in combination with calcium reduces the risk of hip and non-vertebral fractures by 25% and 20%, respectively, compared with placebo (110809). However, discrepancies exist which are possibly related to the dose and form of calcium used in combination with vitamin D and/or the patient population. Some research shows that taking vitamin D 800 IU daily in combination with calcium 1200 mg daily as tricalcium phosphate reduces fracture risk by up to 31% while taking vitamin D with calcium carbonate does not reduce fracture risk (12929,14282,16878,110809). Some individual clinical studies in postmenopausal females aged 50-79 years show that taking vitamin D plus calcium daily for 2-7 years does not prevent fractures when compared with placebo (14282,16878). Other confounding variables include the possible additional effects of hormonal therapy when given with calcium to postmenopausal adults and/or the inclusion of institutionalized patients with unclear osteoporotic status (95822,97296). Most research shows that taking vitamin D in combination with omega-3 fatty acids does not prevent fractures. A large clinical study shows that taking vitamin D 2000 IU daily alone or with omega-3 fatty acids 1 gram daily and/or strength training three times weekly does not prevent fractures in adults over 70 years of age when compared with placebo (104619). Another large clinical trial shows that taking vitamin D 2000 IU daily, alone or with omega-3 fatty acids 1 gram daily, over approximately 5 years does not prevent overall fractures, nonvertebral fractures, or hip fractures in adults over 50 (males) or 55 (females) years old when compared with placebo. Although the osteoporosis status of the population was unclear, findings were consistent in adults at high fracture risk based on use of osteoporosis medications and/or a history of fragility fractures (109059). As of April 2018, the US Preventative Services Task Force (USPSTF) recommends against supplementing with vitamin D 400 IU daily or less along with calcium 1000 mg daily or less for preventing primary fractures in community-dwelling postmenopausal adults. The USPSTF also concludes that there is insufficient evidence to determine whether supplementing with doses of vitamin D greater than 400 IU daily along with calcium doses greater than 1000 mg daily is safe or effective for preventing fractures in community dwelling adults without vitamin D deficiency, osteoporosis, or a history of fracture (95695). For information on patients WITH osteoporosis, refer to the Osteoporosis discussion. There is limited research available regarding the effects of vitamin D supplementation for fracture prevention in children. Preliminary research in children aged 2 to 17 years with vitamin D insufficiency and one or more previous fractures shows that taking vitamin D 2000 IU daily with calcium 600 mg daily for 6 months modestly reduces the risk of forearm fractures over 12 months compared with children not given vitamin D or calcium (110820).
Hypertension. Overall, vitamin D does not seem to prevent or lower high blood pressure in most patients; however, it may lower blood pressure in hypertensive patients with vitamin D deficiency. Details: Although population research has found that lower vitamin D levels are associated with a higher risk of developing hypertension, clinical research shows vitamin D supplementation does not prevent hypertension (15630). A large clinical trial in postmenopausal adults shows that taking vitamin D3 400 IU with calcium 1000 mg daily does not reduce the risk of developing hypertension (16714). Most meta-analyses and clinical trials in patients with existing hypertension show that vitamin D supplementation does not lower blood pressure when compared with placebo, regardless of vitamin D formulation, dose, or duration of supplementation (16714,91340,96405,103657,104619,113583,113668). However, a meta-analysis of 5 clinical studies in patients with hypertension and vitamin D deficiency shows that supplementation with vitamin D reduces systolic and diastolic blood pressure by about 7 mmHg and 3 mmHg, respectively, when compared with placebo (100895). Another meta-analysis of 11 clinical trials in patients over 60 years of age with hypertension and vitamin D deficiency shows that taking vitamin D supplements significantly reduces systolic, but not diastolic, blood pressure when compared with placebo, especially in trials lasting more than 8 weeks where the total dose of vitamin D is above 400,000 IU (113592). An individual clinical study in patients with hypertension and vitamin D deficiency or insufficiency shows that taking vitamin D 50,000 IU weekly or 1000 IU daily reduces systolic blood pressure by about 6 mmHg and mean arterial pressure by about 4 mmHg, but does not affect diastolic blood pressure, when compared to baseline (108440).
Prostate cancer. Oral vitamin D does not appear to affect prostate cancer progression or cancer-related mortality. Details: A meta-analysis of three clinical trials shows that vitamin D supplementation does not affect prostate cancer progression as measured by prostate-specific antigen (PSA), or mortality in patients with prostate cancer (99770).
Psychosis. Oral vitamin D does not seem to improve symptoms in patients with a functional psychotic disorder. Details: A clinical study in adults with a functional psychotic disorder shows that taking oral vitamin D3 (cholecalciferol) 20,000 IU monthly for 6 months has no effect on total positive and negative syndrome scale score (PANSS) when compared with placebo. The majority of patients included in this study were deficient in vitamin D at baseline (107226).
Tuberculosis. Oral vitamin D seems to be ineffective for reducing the severity of tuberculosis or mortality from tuberculosis. Limited research suggests that vitamin D may have small benefits in newly diagnosed patients receiving tuberculosis treatment for the first time. Details: Although population research has found that tuberculosis is associated with vitamin D deficiency, most clinical research shows that taking vitamin D does not improve clinical outcomes in people with tuberculosis infection. Meta-analyses and individual clinical studies show that taking vitamin D as a single 100,000 IU dose, or as 400 IU daily for 2 months, along with standard care does not improve tuberculosis severity or reduce the risk of mortality in children or adults with tuberculosis, regardless of their baseline vitamin D levels (82570,82475,98913,103655,103668,104022). However, some research has identified modest benefits in newly diagnosed patients receiving anti-tuberculosis treatment for the first time. A meta-analysis of clinical research in this population shows that taking vitamin D at a dose of 1000 IU daily or 600,000 IU monthly modestly increases the odds of sputum smear conversions by 1.2-fold, but does not improve the time to sputum smear conversions, when compared with placebo (98235). A small clinical study in treatment-naïve adults with low levels of serum vitamin D shows that taking calcitriol 0.25 mcg twice daily for up to 6 months, starting with anti-tuberculosis treatment initiation, decreases the time to sputum smear conversion and 50% lesion absorption by about 3 days when compared with not taking vitamin D (109045). Additionally, a small clinical study in children aged 6-18 years with vitamin D insufficiency receiving standard treatment for newly diagnosed pulmonary tuberculosis shows that taking vitamin D 1000 IU daily reduces the duration of fever and cough by 1 and 2 weeks, respectively, when compared with placebo (108437).

INSUFFICIENT RELIABLE EVIDENCE to RATE

Acne. It is unclear if oral vitamin D is beneficial for acne. Details: A small clinical trial in patients with acne and vitamin D deficiency shows that taking cholecalciferol 1,000 IU daily for 2 months reduces the number of inflammatory lesions by about 35%, compared with 6% in those taking placebo. There was no effect on the total or non-inflammatory lesion count (106127). Other preliminary clinical research shows that taking alfacalcidol (One Alpha, LEO Company, Denmark) 0.25 mcg daily for 3 months modestly improves acne severity when compared with taking placebo (106128). In addition, population research has found that individuals with acne have modestly lower vitamin D levels than healthy controls. The odds of vitamin D deficiency were approximately three times higher in patients with acne when compared with healthy controls (106105).
Age-related cognitive decline. It is unclear if oral cholecalciferol is beneficial for preventing age-related cognitive decline. Details: Pooled results of two large clinical sub-studies in community-dwelling adults aged 60 years or older show that taking cholecalciferol 2000 IU daily for 2-3 years has no effect on cognitive decline when compared with placebo. A subgroup analysis in Black patients suggests a modest effect of vitamin D when compared with placebo (108428).
Alzheimer disease. It is unclear if oral vitamin D is beneficial for this condition. Details: Some population research has found that lower serum concentrations of vitamin D are associated with higher risk of Alzheimer disease, and also with decreased cognition. People with Alzheimer disease seem to have serum concentrations of vitamin D that are about 2.5 ng/mL lower than patients without Alzheimer disease (84672,103666). However, other population research has found that vitamin D deficiency (<25 nmol/L) or insufficiency (25-50 nmol/L) is not associated with increased risk of Alzheimer disease (100899).
Asthma. Oral vitamin D might reduce asthma exacerbations in adults and children with mild, but not severe or persistent, asthma. Vitamin D supplementation during pregnancy or the first 6 months of an infant's life does not seem to prevent the development of asthma later in infancy or childhood. Details: Population research in patients with asthma suggests that low vitamin D levels are associated with an increased risk of exacerbations and increased need for medication therapy (94693). However, findings from clinical research are mixed. Some meta-analyses of clinical trials in adults and children with asthma show that taking vitamin D for 3 months to 1 year reduces the rate of asthma exacerbations by 31% to 36% when compared with control (92690,94686). However, findings from more recent meta-analyses show that vitamin D supplementation does not reduce the risk of asthma exacerbations when compared with placebo (109728,109732,110833). The reasons for this discrepancy are not clear. However, some clinical research suggests that vitamin D supplements might only prevent asthma in people with non-persistent asthma (92690,94685,94686,94688,104020). Also, many studies are small and do not represent patients with severe asthma exacerbations (92690,94687). Baseline levels of vitamin D may play a role. A clinical study in children aged 6-16 years with persistent asthma and low vitamin D levels shows that taking vitamin D 4000 IU daily for 48 weeks does not reduce severe asthma exacerbations when compared with placebo (104020). However, a meta-analysis including this study shows that taking vitamin D does reduce risk of asthma exacerbations in children with low baseline vitamin D levels (109728). One meta-analysis shows that taking vitamin D seems to modestly improve pulmonary function when compared with placebo (109732). Vitamin D doses have varied, with oral doses of 500-4000 IU daily, 1000 IU once weekly, 60,000 IU once monthly, 120,000 IU every 2 months, 100,000 IU 14 days apart, or 100,000 to 600,000 IU as a bolus dose followed by 400-4000 IU daily (92690,94686,104020,109728,110833). Vitamin D supplementation for the prevention of asthma in infants has also been evaluated. A meta-analysis of 4 large clinical studies shows that taking vitamin D 400-1200 IU daily for the first 6 months of life does not reduce the risk of asthma or wheezing at 6-30 months of age when compared with control (112031). Vitamin D supplementation during pregnancy has also been evaluated (97306,99763,102146,112031). A meta-analysis of 3 large clinical studies shows that taking vitamin D 2800-4400 IU daily during the 2^nd and 3^rd trimesters of pregnancy reduces the risk of recurrent wheezing by 23% but does not reduce the risk of asthma diagnosis within the first 3-6 years of life when compared with vitamin D 400 IU daily (112031). Some research suggests that the dose of vitamin D plays a role. A meta-analysis shows that prenatal vitamin D 800 IU daily reduces the odds of wheeze or asthma by 32%, while lower or higher vitamin D doses were not beneficial (103661).
Athletic performance. It is unclear if oral vitamin D is beneficial for athletic performance. Details: One small clinical trial in athletes shows that taking vitamin D 20,000 or 40,000 IU once weekly for 2 doses does not affect performance on vertical jumps, sprints, or leg and bench presses when compared with placebo (98188). Another small clinical trial in professional rugby players shows that taking vitamin D3 (cholecalciferol) 50,000 IU once every two weeks over 12 weeks does not improve sprinting speed or the ability to perform bench presses, bench pulls, and chin-ups when compared with placebo (98189). Also, most research shows that taking vitamin D does not improve measures of cardiorespiratory fitness. One small study in young males undergoing resistance training shows that taking vitamin D 8000 IU daily for 12 weeks does not improve cardiorespiratory fitness compared with taking placebo (110812).
Atopic dermatitis (eczema). Most research shows that oral vitamin D reduces eczema severity in children. However, most research shows that oral vitamin D, taken during pregnancy or infancy, does not prevent eczema in the child. Details: A meta-analysis of eight moderate-quality clinical trials in children shows that taking vitamin D, most commonly 1000-2000 IU daily for 4-12 weeks, modestly reduces severity of eczema when compared with placebo (109728). Most of the children in these studies were also given conventional medications. Oral vitamin D has also been evaluated for eczema prevention. A meta-analysis of two clinical studies shows that consuming vitamin D 2800-4400 IU daily during the 2^nd and 3^rd trimesters of pregnancy is not associated with a reduced risk for eczema in children during the first 3 years of life when compared with vitamin D 400 IU daily (97306). Another meta-analysis of five large clinical studies shows that prenatal or infant vitamin D supplementation does not reduce the risk of developing eczema when compared with low-dose vitamin D, placebo, or no intervention (108438).
Atrial fibrillation. It is unclear if oral vitamin D is beneficial for preventing atrial fibrillation. Details: A large clinical trial in adults without cardiovascular disease shows that taking vitamin D 2000 IU daily for an average of 5 years does not reduce the incidence of atrial fibrillation when compared with placebo or fish oil 840 mg daily (105209). However, observational research in postmenopausal adults with osteoporosis found that vitamin D supplementation is associated with a lower occurrence of atrial fibrillation when compared with not taking vitamin D (98922). Also, one large observational study in vitamin D-deficient patients with no history of atrial fibrillation has found that vitamin D supplementation for at least 6 months is associated with up to a 16% decreased risk of atrial fibrillation when compared with not taking vitamin D. There were also modest improvements in atrial fibrillation-free survival. In males 65 years and older with hypertension or diabetes at baseline, blood levels of at least 30 ng/mL following vitamin D supplementation were associated with decreased risk of atrial fibrillation; a post-supplementation blood level of 21-29 ng/mL was not associated with decreased risk (109043).
Attention deficit-hyperactivity disorder (ADHD). It is unclear if oral vitamin D is beneficial for ADHD. Details: A small clinical trial in children 5-12 years of age with ADHD and vitamin D insufficiency shows that taking vitamin D 2000 IU daily along with methylphenidate for 8 weeks seems to improve parental ratings of evening, but not morning or overall, symptoms of inattentiveness and impulsivity when compared with methylphenidate alone. Vitamin D insufficiency was defined as levels less than 30 ng/mL (98196). Based on these and other preliminary findings, Guidelines from The World Federation of Societies of Biological Psychiatry (WFSBP) and Canadian Network for Mood and Anxiety Treatments (CANMAT) Taskforce state that vitamin D in doses of 1500 to 4000 IU daily is weakly recommended for adjunctive use in children with ADHD, especially those with insufficient intake or skin exposure to sunlight (110318).
Autism spectrum disorder. It is unclear if oral vitamin D is beneficial for autism spectrum disorder. Details: A small clinical study in children aged 2.5-8 years with autism spectrum disorder shows that taking vitamin D 2000 IU daily for 12 months modestly reduces irritability and hyperactivity when compared with placebo (99767).
Autoimmune thyroiditis. It is unclear of oral vitamin D improves outcomes in patients with Hashimoto's thyroiditis. Details: A meta-analysis of 12 clinical trials in patients with Hashimoto's thyroiditis shows that taking vitamin D for at least 12 weeks increases free triiodothyronine (T3) and thyroxine (T4) levels, and reduces levels of thyroid stimulating hormone, thyroglobulin antibody, and anti-thyroid peroxidase antibody, when compared with placebo or no treatment (113593).
Bacterial vaginosis. It is unclear if oral vitamin D is beneficial for bacterial vaginosis. Details: Preliminary clinical research in females at high risk for sexually transmitted disease shows that taking vitamin D along with standard therapy for bacterial vaginosis does not reduce the prevalence of bacterial vaginosis when compared with placebo. Patients in this study had been treated with metronidazole 500 mg orally twice daily for 7 days along with vitamin D3 (cholecalciferol) 50,000 IU each week for 4 weeks and then every 4 weeks for the remaining 20 weeks (91348).
Breast cancer. It is unclear if oral vitamin D is beneficial for the prevention of breast cancer. Details: Some population research evaluating intake of calcium plus vitamin D suggests that higher vitamin D intake is not associated with a reduced risk of breast cancer in premenopausal or postmenopausal adults (15631). Similarly, a large observational study in females with a biological sibling with breast cancer has found that taking vitamin D recently or prior to enrollment is not associated with a reduced risk of breast cancer when compared with nonrecent vitamin D use or never taking vitamin D, respectively (107215). However, other research found that higher vitamin D intake is associated with a 17% reduced risk of breast cancer in premenopausal and perimenopausal, but not postmenopausal, adults (39001). Observational research has also examined the association between blood levels of vitamin D and risk of developing breast cancer. A meta-analysis found that those with serum levels of about 52 ng/mL had a 50% lower risk of developing breast cancer when compared with those with serum levels of less than 13 ng/mL. This high serum level of vitamin D corresponds to a high dose of about 4000 IU daily (16049). Other observational research has found that baseline vitamin D levels of more than 20 ng/mL are associated with a 48% reduced risk of developing breast cancer over approximately 9 years in Latina females in the US when compared with levels below 20 ng/mL; however, this association was not present in Black females (109058). Despite the contradictory findings from observational research, results from clinical research are generally negative. Evidence from one large-scale clinical trial (Women's Health Initiative) shows that postmenopausal adults who take vitamin D3 (cholecalciferol) 400 IU daily plus calcium 1000 mg daily for 7 years do not have a significantly reduced risk of developing breast cancer (16715,98895). Also, a meta-analysis of two large-scale clinical trials, which did not include the Women's Health Initiative trial, shows that taking vitamin D 800-1000 IU daily, alone or with calcium, for 3-4 years does not reduce the incidence of breast cancer in postmenopausal adults, although there was a trend towards reduced risk with higher doses of vitamin D supplementation (97301). While vitamin D and calcium supplementation during the intervention period of the Women's Health Initiative trial was not associated with a reduced risk of developing breast cancer or ductal carcinoma in situ (DCIS), a precursor to breast cancer, a secondary post-hoc analysis of the data shows that supplementation reduces the risk of developing DCIS by 18% over a median follow-up of 19 years (107216). Additional research is needed regarding an optimal dose of vitamin D, timing of initiation, and whether any benefit is affected by menopausal status.
Bronchopulmonary dysplasia. Limited research suggests that vitamin D deficiency is linked with bronchopulmonary dysplasia in the infant. Details: Observational research has found that vitamin D deficiency at birth is associated with about a 2-fold increased odds of developing bronchopulmonary dysplasia (104021). However, it is unclear if vitamin D supplementation is beneficial.
Cancer. Vitamin D does not seem to reduce overall cancer risk. However, some research shows that vitamin D might slightly reduce the risk of metastatic cancer and cancer-related mortality. Details: There is interest in vitamin D for cancer PREVENTION, as observational research suggests that higher vitamin D intake and higher 25-hydroxyvitamin D levels are associated with a lower risk of cancer (111150). While individual clinical trials evaluating vitamin D for cancer have produced inconsistent findings, most meta-analyses and clinical trials show that taking vitamin D3 (cholecalciferol) or vitamin D2 (ergocalciferol) alone or with calcium does not significantly reduce the risk of developing cancer (15629,91344,93943,97296,98916,104024,104618,110811). However, vitamin D supplementation might reduce the risk of metastatic cancer and cancer-related mortality. A large clinical trial shows that taking vitamin D3 2000 IU daily for a median of 5.3 years slightly reduces the risk of advanced metastatic or fatal cancers when compared with placebo (104618). Additionally, meta-analyses of several large clinical trials show that taking vitamin D 400-4000 IU daily, with or without calcium, for 1-7 years reduces the risk of cancer-related mortality by 12-13% when compared with control, while intermittent bolus dosing of vitamin D at high doses for 1-5 years does not appear to reduce the risk of cancer-related mortality (104024,111149). The role of vitamin D in cancer TREATMENT is unclear. A meta-analysis of clinical and observational research suggests that supplementation of vitamin D after a cancer diagnosis is associated with a modest improvement in overall survival, but not progression-free or cancer-specific survival (109726). Doses used in clinical research ranged between 1200 IU and 8000 IU daily or 100,000 IU every 50 days, after surgery and/or during treatment (99195,99196,109726). Other clinical research in patients with luminal gastrointestinal cancers shows that taking vitamin D 2000 IU daily does not reduce the risk of relapse when compared with placebo (99195). It is unclear which, if any, types or stages of cancer respond best to vitamin D, and what dose of vitamin D is optimal.
Child growth. It is unclear if oral vitamin D is beneficial for improving infant growth or bone structure. Details: Meta-analyses and individual clinical trials show that vitamin D supplementation during pregnancy modestly increases length at birth and bone mineral density at up to 6 years of age when compared with control, usually placebo or vitamin D 400 IU daily. However, there was no effect on length in the infant up to one year of age, weight at birth or up to one year of age, head circumference at birth or up to 6 years of age, bone mineral content at up to 6 years of age, or neonatal bone mineral density, bone mineral content, bone area, or femur or humoral length (98198,109737,112028). In the available research, vitamin D was taken in doses of 200 IU to 4400 IU daily, 4200 IU to 50,000 IU weekly, 50,000 IU every 2 weeks, or 60,000 IU every 4-8 weeks, starting from the early to late stages of pregnancy and usually continued until birth (98198,109737).
Chronic kidney disease (CKD). It is unclear if oral vitamin D is beneficial in patients with CKD. Most research suggests that it does not reduce the risk for adverse cardiovascular events. Details: Population research in patients on dialysis has found that vitamin D levels less than 17.8 ng/mL are associated with a higher risk of all-cause mortality compared with higher levels (16619). A meta-analysis and individual clinical studies show that vitamin D and vitamin D analogues decrease parathyroid hormone (PTH) levels and urine protein levels in people with CKD (84376,84377,84628,98233,98236). However, taking vitamin D does not appear to decrease the risk of death or parathyroidectomy in CKD patients (84376,84377). Also, taking vitamin D increases the risk for hypercalcemia and hyperphosphatemia in this patient population (84376,84377,98236). Vitamin D has also been evaluated for the prevention of cardiovascular events in adults with CKD. Observational research has found that vitamin D deficiency in patients with CKD is associated with adverse cardiovascular events. However, vitamin D supplementation does not seem to be beneficial. One clinical study shows that taking paricalcitol, an active form of vitamin D, titrated to maintain adequate serum calcium levels, for 48 weeks does not affect the size of the left ventricle or heart function when compared with placebo (98233). Other clinical research in Japanese patients on hemodialysis for CKD shows that adding alfacalcidol, another active form of vitamin D, 0.5 mcg daily to standard treatment for 4 years does not affect mortality or cardiovascular events such as myocardial infarctions, stroke, aortic dissection, and others compared to standard treatment only (98920). Also, a large clinical trial in patients with CKD shows that taking vitamin D as cholecalciferol 2000 IU daily, alone or with omega-3 fatty acids 1 gram daily, does not affect major cardiovascular events or invasive cancer when compared with placebo (110811). Vitamin D has also been evaluated for musculoskeletal health in adults with CKD. A small clinical study shows that taking cholecalciferol 4000 IU daily, with or without physical activity, for 3 months improves bicep strength, but not back flexibility or aerobic fitness capacity, when compared with baseline. In patients taking cholecalciferol in combination with physical activity, musculoskeletal health was similar when compared with cholecalciferol alone (108431). However, this study was inadequately powered to detect a difference between groups, and it is unclear if the improvement from baseline differed between groups. Vitamin D has also been evaluated for the improvement of iron status in adults with CKD and secondary hyperparathyroidism. Clinical research shows that taking Vitamin D as cholecalciferol (Vitamin D3 Forte Renapharma) 8000 IU daily for 12 weeks does not improve iron status compared with taking placebo. However, a sub-analysis shows that hemoglobin levels are modestly improved in patients with a low Vitamin D status at baseline suggesting that Vitamin D might improve iron availability in these patients (110819).
Chronic obstructive pulmonary disease (COPD). It is unclear if oral vitamin D is beneficial for COPD; benefits may be limited to patients with vitamin D deficiency. Details: Population research has found an association between low vitamin D levels and reduced lung function, increased risk of developing COPD, and worsening COPD severity (17685,96401). In contrast, 2 meta-analyses of clinical research in adults with COPD and with or without vitamin D deficiency show that oral vitamin D does not have beneficial effects on mortality, rate of COPD exacerbations, pulmonary function, or most measures of symptom severity when compared with placebo (109732,112485). However, other research suggests that vitamin D may be beneficial in patients with vitamin D deficiency. Some clinical research in patients with moderate to severe COPD and severe vitamin D deficiency shows that taking a specific vitamin D supplement (D-Cure, Laboratoires SMB) 100,000 IU once every 4 weeks for 1 year seems to reduce the rate of exacerbations by 43% when compared with placebo (98194).
Cognitive function. It is unclear if oral vitamin D is beneficial for cognitive function. Details: Population research has found that low vitamin D levels are associated with worse cognitive performance and cognitive decline when compared to high vitamin D levels in healthy adults (84672,95916). However, the effect of vitamin D supplementation on cognitive function is unclear. One small meta-analysis of clinical research shows that vitamin D supplementation does not improve cognitive function (95916). However, the included trials evaluated a widely heterogeneous study population and utilized variable measures of cognitive function.
Cognitive impairment. It is unclear if oral vitamin D is beneficial for older adults with mild cognitive impairment. Details: A small clinical study in older adults with mild cognitive impairment shows that taking vitamin D3 10,000 IU three times weekly for 20 weeks in addition to exercise and cognitive training does not improve cognitive function when compared with placebo and exercise with or without cognitive training. However, most participants had sufficient serum vitamin D levels at baseline (112489).
Colorectal cancer. It is unclear if oral vitamin D is beneficial for the treatment or prevention of colorectal cancer. Details: Epidemiological research has found that a higher serum vitamin D level is associated with decreased risk of mortality and increased survival in patients with colorectal cancer (16101,99196). However, it is unclear whether vitamin D supplementation improves survival in patients with colorectal cancer, as research has generally involved small populations and results are somewhat conflicting. A subgroup analysis of one clinical study shows that taking vitamin D 2000 IU daily does not reduce the risk of relapse or death, death due to any cause, or relapse over 5 years when compared with placebo in patients with colorectal cancer (99195). However, this subgroup may have been underpowered to detect between-group differences. Another small clinical trial in patients with advanced or metastatic colorectal cancer shows that taking high-dose vitamin D 8000 IU daily during the first cycle of chemotherapy, and then 4000 IU daily for subsequent cycles, does not increase median progression-free survival when compared with taking vitamin D 400 IU daily. However, patients taking high-dose vitamin D were 36% less likely to experience disease progression or death during follow-up when compared with patients taking the lower dose of vitamin D (99196). This latter result suggests that high-dose vitamin D supplementation might be beneficial for patients with advanced or metastatic colorectal cancer, but larger, multicenter studies are needed to confirm. The role of vitamin D in colorectal cancer prevention has also been investigated. A meta-analysis of epidemiological research has found that a higher serum vitamin D level is associated with a decreased colorectal cancer risk; however, sub-analyses suggest that this association only occurs in females, not males (109740). Most studies have evaluated vitamin D supplements in combination with calcium; the effects of vitamin D supplementation alone are unclear. One meta-analysis of clinical research suggests that taking vitamin D plus calcium is not associated with a decreased incidence of colorectal cancer in people with a low baseline risk of colorectal cancer (39042). Another meta-analysis of clinical research shows that vitamin D supplementation, with or without calcium, does not reduce the incidence of colorectal cancer or colorectal adenomas (109730). Additionally, a large clinical trial suggests that postmenopausal adults who take calcium 1000 mg daily plus vitamin D 400 IU daily do not have a reduced risk of developing colorectal cancer (14290,98895). One clinical study shows that taking calcium supplements reduces the risk of colorectal adenomas, but not in people with lower than average vitamin D levels (12118).
Coronavirus disease 2019 (COVID-19). The evidence is mixed with respect to oral vitamin D supplementation for the prevention and treatment of COVID-19. Also, although some observational research has suggested a correlation between vitamin D status and risk for COVID-19, not all studies agree, and this association may be due to other confounders such as age and comorbidities. Details: Clinical and observational research has evaluated vitamin D supplementation for COVID-19 prevention. A preliminary clinical trial shows that oral vitamin D 800 IU or 3200 IU daily for 6 months in individuals with lower serum levels of vitamin D does not reduce the risk of COVID-19 or any respiratory tract infection when compared with no vitamin D supplementation (109721). However, groups were not matched for baseline vitamin D status and many individuals in the untreated group took their own vitamin D supplements. Two meta-analyses of clinical and observational studies show no relationship between vitamin D supplementation and the primary prevention of COVID-19 infection, although baseline vitamin D status is unclear (109040,112488), However, an umbrella meta-analysis of clinical and observational research suggests that vitamin D deficiency is associated with a greater risk of COVID-19 infection, COVID-19 severity, and mortality (114583). Also, a quasi-experimental cohort study in Italian adults who had supplemented with vitamin D in the 3 months prior to COVID-19 diagnosis found no reduction in risk for hospitalization, as well as a trend towards increased risk for in-hospital mortality, when compared with those who had not received vitamin D supplementation (104625). However, some research disagrees. Clinical research in highly exposed healthcare workers shows that taking vitamin D as cholecalciferol 4000 IU daily for 30 days reduces the risk of COVID-19 infection by 77% when compared with placebo (109052). Also, in the UK population, observational research has found that habitual use of vitamin D supplements between 2006 and 2010 is associated with a 34% lower risk of COVID-19 infection. This finding remained positive after adjusting for baseline health status and use of other micronutrients (104717). A meta-analysis of 16 studies in various populations shows that vitamin D reduces the risk of COVID-19 infection by 40% to 60% (113590). Vitamin D supplementation as treatment in outpatients with COVID-19 has also been evaluated. Preliminary clinical research discussed in a systematic review suggests that supplementation might be associated with less severe symptoms; however, there is inadequate information to determine if supplementation in patients with mild symptoms is associated with reduced hospital admission (109040). Conversely, a large cross-sectional study found an association between pre-hospital supplementation and increased risk for COVID-19, as well as increased rates of death and/or invasive mechanical ventilation. However, this association was no longer significant after adjusting for sex, age, and comorbidities (107205). Most research on vitamin D supplementation has been conducted in children and adults hospitalized with COVID-19. However, meta-analyses of clinical and observational research in these patients provides conflicting results on whether vitamin D supplementation as single dose or multiple doses is associated with a reduced risk of mortality, length of hospitalization, admission to the intensive care unit (ICU), or need for ventilation when compared with placebo or standard care alone (109040,109733,112488,112490,113579,114488,114583). The quality of evidence of most individual clinical trials is low to moderate due to a lack of placebo and blinding in many of the studies. Most individual studies evaluating single doses of vitamin D, administered either after diagnosis or after hospital admission, have not identified benefit for major outcomes, such as hospital length of stay, in-hospital mortality, or ICU admission. Many of these studies were small, low quality, and conducted in heterogenous populations, with doses ranging from 80,000 IU to 500,000 IU (104624,104626,107208,108434,109051,112490). Additionally, meta-analysis of 11 clinical studies primarily in patients hospitalized with mild to severe COVID-19 shows that taking vitamin D does not reduce the risk of all-cause mortality, regardless of baseline vitamin D status, when compared with control. However, sensitivity analysis shows that multiple administration of vitamin D reduces the risk of all-cause mortality by 33% when compared with single administration (114488). One small, unblinded study in at-risk older adults admitted to the hospital or living in a long-term care facility shows that taking a single dose of 400,000 IU within 72 hours of diagnosis modestly improves survival at 14 days, but not 28 days, when compared with 50,000 IU (109039). The evidence related to multi-dose regimens in hospitalized patients is mixed. A cohort study shows that giving calcifediol 0.532 mg at hospital admission, followed by calcifediol 0.266 mg on days 3 and 7 and then weekly until discharge or ICU admission, reduces odds of in-hospital death within 30 days by 78% when compared with those not given vitamin D (106099). A small clinical trial in patients with vitamin D deficiency shows that taking vitamin D 25,000 IU daily for 4 days and then weekly for up to 6 weeks reduces length of hospital stay and duration of supplemental oxygen by 4 days and 3 days, respectively, and also reduces disease severity and ICU admission after 7 days (109050). A small, unblinded study in patients with suboptimal vitamin D status and mild to moderate COVID-19 shows that taking vitamin D3 5,000 IU daily for 2 weeks reduces the time to recovery from cough and loss of taste by 2.9 and 5.5 days, respectively, when compared with vitamin D3 1,000 IU daily. However, there was no difference in time to recovery from fever, dyspnea, body aches, or other symptoms (106117). However, some research disagrees. A small unblinded study has found that although vitamin D status at 9 days is negatively associated with the number of bed days, vitamin D 50,000 IU on days 1 and 8 does not affect the number of bed days, time to discharge, or ICU admission when compared with no supplementation (109047). An additional preliminary study in patients with severe COVID-19 and low blood levels of vitamin D shows that taking vitamin D (Plivit D3, Pliva) 10,000 IU daily while in the ICU or for at least 14 days does not reduce the number of days on respiratory support, or in the ICU or hospital, or improve survival rates when compared with no supplementation (110813). A small, open-label study in patients hospitalized with COVID-19 pneumonia shows that taking alfacalcidol 2 mcg orally daily dose not reduce the duration of treatment or length of hospital stay (113579). The relationship between vitamin D levels and COVID-19 has also been evaluated in pregnant patients. A meta-analysis of observational research suggests that, while lower vitamin D levels are not associated with an increased risk of COVID-19, the presence of severe COVID-19 symptoms in pregnant patients may be linked to lower vitamin D levels when compared with non-severe COVID-19 symptoms (112025). Limited research has investigated the effect of vitamin D in combination with other ingredients. Preliminary clinical research in patients with mild to moderate COVID-19 shows that taking vitamin D3 (Davalindi, Medical Union Pharma, Cairo, Egypt) 2000 IU daily in combination with black seed (Baraka, Pharco Pharmaceuticals, Cairo, Egypt) 900 mg twice daily for 14 days modestly reduced the severity of some symptoms, including cough, diarrhea, fatigue, and pharyngitis, as well as the percent patients with viral positivity at day 7, but not headache, rhinorrhea, anosmia, or shortness of breath, or vomiting, when compared to standard care alone. However, taking vitamin D alone did not provide significant benefit (110265). The validity of individual studies is limited by generally poor designs. More research is needed to evaluate varying vitamin D dosing levels and schedules, as well as evaluated outcomes, and whether patients with vitamin D insufficiency are more likely to benefit from vitamin D supplementation. The relationship between vitamin D status and risk of COVID-19 infection or severe disease is unclear. Despite some observational research suggesting that low vitamin D levels are associated with an increased risk for COVID-19 mortality, development of severe disease, such as pulmonary involvement, and extended hospitalization or admission to intensive care (107206,107207,108434), several meta-analyses of observational research as well as individual observational studies have found that vitamin D deficiency in adults is not associated with a higher risk for COVID-19 infection or with disease severity or mortality (104627,107208,107209). Additional observational research has found no association between vitamin D status and hospital length of stay, need for mechanical ventilation, mortality, or experiencing persistent feelings of fatigue or reduced exercise tolerance, otherwise known as "long-COVID" (106102,106116,106120,107206). However, one meta-analysis has found that when compared with mild disease, 65% more individuals with severe disease had vitamin D deficiency. Also, vitamin D insufficiency, defined as blood levels less than 30 ng/mL, is associated with a more than 80% increased chance of hospitalization or mortality due to COVID-19. Notably, many of these studies did not control for patient age or other comorbidities (104627). A more recent observational study has found that vitamin D status in patients with severe COVID-19 symptoms is inversely correlated with both ICU admission and death, with a 1% reduction in risk of ICU admission and 4% reduction in risk of death for every 1 ng/mL increase in 25-hydroxyvitamin D (106112). In one individual observational study, the association between vitamin D status and COVID-19 infection is no longer significant after adjusting for socioeconomic status, age, health status, body mass index, ethnicity, and other covariates (104628). In contrast, a small observational study of adults admitted to the hospital with COVID-19 has found that low vitamin D levels are associated with an increased risk of mechanical ventilation and in-hospital mortality, even after adjustment for ethnicity and pre-existing conditions, such as cardiovascular disease, respiratory disease, and diabetes. However, this study is small and does not adjust for socioeconomic factors (105720). Also, another individual observational study has found that the likelihood of testing positive for COVID-19 is increased in Black, but not White, adults who had a vitamin D level of 30-40 ng/mL at some point in the past year when compared with a level of at least 40 ng/mL, with risk decreasing as levels increased from 30 ng/mL to 40 ng/mL (104716). Patients should be encouraged to maintain adequate vitamin D levels. A joint task force has recommended 400-1000 IU (10-25 mcg) daily for those who are unable to spend 15-30 minutes in the sun each day (103659,104629).
Crohn disease. Limited evidence suggests that vitamin D reduces relapses in patients with Crohn disease. Details: A meta-analysis of small, low-quality clinical studies in patients with IBD, including Crohn disease and ulcerative colitis, shows that taking high- or low-dose vitamin D for up to 1 year reduces the rate of relapse when compared with control (98915). The validity of these findings is limited by the heterogeneity of the included studies.
Dementia. It is unclear if oral vitamin D is beneficial for dementia. Details: Population research has found that patients with any type of dementia have serum concentrations of vitamin D that are about 2.5 ng/mL lower than patients without dementia (84672). However, it is unclear if vitamin D supplementation is beneficial.
Depression. It is unclear if oral vitamin D is beneficial for treating depression. Vitamin D does not seem to prevent the development of depression. Details: The role of vitamin D in the treatment of depression is unclear. Earlier meta-analyses of clinical research show that vitamin D supplementation does not improve overall symptoms of depression. However, some subgroup analyses suggest that vitamin D may be beneficial for improving the symptoms of depression in people with clinically significant symptoms, as well as those with baseline vitamin D deficiency (97295,97298). More recent meta-analyses of several clinical trials, that include some of the same studies, show that vitamin D modestly improves symptoms of depression in adults; however, subgroup analysis suggests that vitamin D does not improve depressive symptoms in older adults (110832,112786). These analyses are mixed over whether baseline vitamin D status affects results (110832,112786) and one of these analyses shows no evidence that the type of depression affects findings (110832). Another meta-analysis of generally small clinical trials in patients with type 2 diabetes and depression shows that taking vitamin D modestly improves depressive symptoms when compared with placebo or no intervention (110814). Although, results of an individual clinical trial in patients with type 2 diabetes are in contrast (108423). The evaluated research implemented one-time doses of 150,000-500,000 IU, as well as daily and weekly doses ranging between 400-5000 IU daily or 5000-100,000 IU weekly for 6 weeks to 2 years, with the most evidence of benefit related to one-time high doses. Cholecalciferol was the most common form of vitamin D used (97295,97298,108423,110814,110832,112786). Significant heterogeneity between studies and the wide variability in dosing strategies limit the validity of these findings, as well as identification of an effective dose or target population. Vitamin D has also been evaluated for the prevention of depression. One large clinical study (VITAL-DEP) in healthy patients 50 years and older shows that taking vitamin D 2000 IU daily for about 5.3 years does not prevent depression or depressive symptoms, or improve mood, when compared with placebo (103670). An analysis of a cohort of patients from the VITAL-DEP trial also shows that taking vitamin D 2000 IU daily for 2 years does not reduce the risk of major depressive disorder or improve mood scores in patients with subthreshold depression or risk factors for late-life depression when compared with placebo (112032). In addition, a meta-analysis of several clinical studies suggests that vitamin D supplementation does not prevent depression based on subgroup analysis of patients without depression at baseline (112786). Based on these and other preliminary findings, Guidelines from The World Federation of Societies of Biological Psychiatry (WFSBP) and Canadian Network for Mood and Anxiety Treatments (CANMAT) Taskforce state that vitamin D in doses of 1500 to 4000 IU daily is weakly recommended for adjunctive or monotherapy use in patients with depression, especially those with insufficient intake or skin exposure to sunlight (110318).
Diabetes. Oral vitamin D might improve glycemic indices in some patients with type 2 diabetes and gestational diabetes. It is unclear if oral vitamin D is beneficial for the prevention of type 1 or gestational diabetes. It is also unclear if intramuscular vitamin D is beneficial for the treatment of gestational diabetes. Details: Most meta-analyses of mainly small clinical trials show that vitamin D supplementation is beneficial for measures of glycemic control in patients with diabetes. However, the best evidence of benefit is in patients with baseline vitamin D deficiency. Three meta-analyses of small trials in patients with type 2 diabetes show that vitamin D supplementation reduces glycated hemoglobin (HbA1c) by 0.20% to 0.25%, and improves serum insulin, fasting blood glucose, and measures of insulin resistance when compared with control (96403,110822,112487). Supplemental vitamin D seems to be most beneficial in patients with baseline vitamin D deficiency (96403,110822,112487). Furthermore, correlation analysis suggests an inverse relationship between serum vitamin D levels and serum insulin, fasting blood glucose, and measures of insulin resistance (112487). However, another meta-analysis of small trials in patients with vitamin D insufficiency or deficiency and type 2 diabetes shows that oral vitamin D modestly improves fasting blood glucose and postprandial blood glucose, but not HbA1c, when compared with control (107210). Most of the evaluated research implemented daily or weekly doses of vitamin D for 4-48 weeks (96403,107210,110822). However, one meta-analysis of clinical research in patients with diabetes shows that vitamin D improves HbA1c, insulin resistance, and insulin measures in studies lasting less than 6 months, but not in studies lasting longer than 6 months (99764). An additional meta-analysis suggests that most evidence of benefit is associated with doses of more than 2000 IU daily for 4-12 weeks (110822). One small, long-term clinical study in middle-aged and elderly patients with type 2 diabetes shows that taking vitamin D 800 IU daily for 30 months reduces insulin levels and insulin resistance when compared with no supplementation. However, there was no effect on HbA1c or fasting blood glucose levels (109734). Thus, conflicting results may be related to the dose and duration of vitamin D supplementation, as well as patient characteristics at time of study entry, such as vitamin D status, baseline HbA1c levels, obesity, and medication regimen (97304,99764,109734,110822). Vitamin D has been evaluated for the prevention of type 1 diabetes. There is preliminary evidence that daily vitamin D supplementation (form not specified) in infants during the first year of life is associated with a reduced incidence of type 1 diabetes development later in life (10139). Also, a meta-analysis of population studies has found that vitamin D supplementation in early childhood is associated with a 29% reduced risk of developing type 1 diabetes later in life (84225). Vitamin D has been evaluated in patients with gestational diabetes. Some research has evaluated the effects of oral or intramuscular vitamin D on glycemic indices. The evidence from clinical research comparing vitamin D with placebo is mixed. Most studies show modest evidence of benefit for some markers of glycemic control. One clinical trial shows that vitamin D modestly reduces levels of insulin, as well as measures of insulin resistance, with no effect on fasting blood glucose (106125). However, other clinical research shows that taking vitamin D modestly reduces levels of fasting blood glucose and HbA1c, with no effect on insulin measures (106126). Two other trials show that taking vitamin D modestly improves all measures of glycemic indices (101775,106122). Additionally, a large clinical trial shows that taking vitamin D 1600 IU daily modestly reduces fasting blood glucose when compared with vitamin D 400 IU daily (112020). Some clinical research has also evaluated the effects of oral vitamin D on lipid indices in patients with gestational diabetes. Although some individual clinical research disagrees (106126), most research shows that taking vitamin D modestly improves levels of low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and triglycerides when compared with control (106125,110823). Also, a meta-analysis of clinical research in patients with gestational diabetes shows that taking vitamin D reduces the risk of premature birth and neonatal hospitalization by approximately 63% and 62%, respectively (110823). Oral vitamin D 50,000 IU (eg. D-Vitin50000; Zahravi Pharm Co.) once or twice monthly, starting at week 24 of gestation and continuing for 6 weeks, 8 weeks, or until delivery, has been used in most of these studies (106122,106125,106126). One study provided oral vitamin D 500 IU twice daily in yogurt from the beginning of the second trimester for 16 weeks (101775). However, other preliminary clinical research shows that giving vitamin D 300,000 IU as a single intramuscular injection at 24-28 weeks' gestation does not affect HbA1c (106124). Some research has examined the effect of vitamin D supplementation on insulin resistance during pregnancy in the absence of gestational diabetes. A meta-analysis of clinical research shows that taking vitamin D for 6 to 26 weeks modestly decreases measures of insulin resistance when compared with placebo. However, there was no evidence to suggest that higher doses were more beneficial than lower doses. Although this population did not have gestational diabetes, these results suggest that adequate vitamin D might be beneficial for its prevention (110821). Vitamin D has also been evaluated in combination with omega-3 fatty acids in adults with gestational diabetes. One study evaluated vitamin D in combination with eicosapentaenoic acid (EPA) 360 mg plus docosahexaenoic acid (DHA) 240 mg twice daily. There is some evidence that this combination offers benefit over vitamin D alone and plasma triglyceride levels were also improved (106122). Other clinical research in patients with gestational diabetes shows that taking vitamin D with omega-3 fatty acids 8,000 mg twice daily for 6 weeks modestly improves glycemic indices and most lipid markers when compared with placebo (106114). Vitamin D has also been evaluated for the prevention of gestational diabetes. A Cochrane analysis of one large clinical study shows that taking vitamin D during pregnancy does not lower the risk of gestational diabetes when compared with no supplementation (114587). In addition, a meta-analysis of population studies suggests that there is a U-shaped association between serum vitamin D concentrations and the risk of developing gestational diabetes, with serum concentrations between 40 and 90 nmol/L associated with the lowest risk (106109).
Diabetic foot ulcers. It is unclear if oral vitamin D is beneficial for diabetic foot ulcers. Details: A meta-analysis of clinical research in patients with diabetic foot ulcers shows that taking vitamin D modestly reduces ulcer size and improves glycemic and lipid indices when compared with placebo (110835). This meta-analysis is limited by the availability of three small clinical trials, as well as the heterogeneous doses of vitamin D in the included studies.
Diabetic nephropathy. Limited evidence suggests that vitamin D improves some markers of kidney function in patients with diabetic nephropathy. Details: A meta-analysis of small clinical studies in patients with diabetic nephropathy shows that taking vitamin D or its analogs reduces inflammatory markers and protein in the urine, but does not affect measures of kidney function such as serum creatinine or glomerular filtration rate, when compared to control (99771).
Diabetic retinopathy. It is unclear if oral vitamin D is beneficial in diabetic retinopathy. Details: There is weak evidence from observational research suggesting a link between vitamin D deficiency and diabetic retinopathy (112095). However, clinical research addressing the effectiveness of vitamin D supplementation for treatment or prevention of diabetic retinopathy is lacking.
Dysmenorrhea. Limited evidence suggests that oral vitamin D reduces pain in patients with dysmenorrhea. Details: A meta-analysis of 9 small clinical studies in patients with dysmenorrhea shows that taking vitamin D in doses ranging from 5000 IU daily to 300,000 IU monthly modestly reduces pain when compared with control (112029). However, the validity of these findings is limited by a high degree of heterogeneity across the studies, including differences in blinding and control interventions, vitamin D doses and frequency of supplementation, and baseline vitamin D levels. Another small clinical study in adolescent patients with dysmenorrhea shows that taking vitamin D3 50,000 IU weekly for 9 weeks modestly reduces pain when compared to baseline (98912). The validity of this finding is limited by the lack of a control group.
Erectile dysfunction (ED). It is unclear if oral vitamin D is beneficial for ED. Details: Although some data suggest ED is associated with low serum 25-hydroxy-vitamin D levels, preliminary research in males aged 60-84 years shows that taking vitamin D 60,000 IU once monthly for up to 5 years does not prevent or improve ED when compared with placebo (113580).
Exercise-induced muscle damage. Small studies suggest that vitamin D does not improve exercise-induced muscle damage. Details: A meta-analysis of 6 small studies shows that taking vitamin D before and/or during exercise does not improve circulating levels of creatine kinase, lactate dehydrogenase, or myoglobin when compared with placebo (107218).
Fall prevention. The role of vitamin D in fall prevention is confusing and controversial. Most clinical research shows that taking vitamin D 800-1000 IU daily decreases the risk of falls, with effects most apparent with daily over intermittent dosing and in those with vitamin D deficiency or insufficiency. Taking vitamin D at doses higher or lower than this may be associated with increased risk of falls. Details: Higher serum levels of vitamin D have been associated with improved lower-extremity function in elderly adults (15636). Clinical research in older adults shows that taking vitamin D or vitamin D analogues, with or without calcium, reduces the number of people who have a fall by up to 19% (39038,84215,84374,84539,94130,104023,113595,114504). Other research shows that vitamin D, with or without calcium, reduces number of falls by 19% to 50% (11939,16275,84404,93941,109053). The beneficial effect does not appear to depend on the form of vitamin D used (ergocalciferol, cholecalciferol, calcitriol, or alfacalcidol) (39038,84374,113595). Multiple meta-analyses of clinical research show that taking vitamin D leads to a decreased rate of falls in patients with low baseline levels of vitamin D, but not in those with adequate vitamin D levels (84670,84684,109053,114504). One meta-analysis also suggests that taking vitamin D as cholecalciferol up to 1000 IU daily reduces fall risk by up to 19%, whereas higher doses do not reduce fall risk (109053). Also, daily dosing, but not intermittent dosing, seems to be associated with a reduced risk of falling (109053,114504). Similarly, another meta-analysis of clinical research shows that taking vitamin D 800-1000 IU daily, with or without calcium, lowers the risk of falls by about 15-26% when compared with placebo, no treatment, or calcium alone. However, taking vitamin D 500 IU or less daily and vitamin D 1100 IU or more daily, with or without calcium, is not associated with a lower risk of falls and may even increase the risk of falls by 22-44% (114504). Despite the above meta-analyses, other clinical research shows that vitamin D does not reduce the risk of falling (84404,84670), the rate of falls overall (84670,93942), or the rate of injurious falls (93942) in elderly patients (93942). One study in adults over 70 years of age with a history of falling found that taking high-dose vitamin D, either as 60,000 IU monthly or 24,000 IU plus calcifediol 300 mcg monthly, increased both the risk of falling and the mean number of falls compared to a lower dose of 24,000 IU monthly (93940). One meta-analysis of 20 trials including nearly 30,000 patients shows that taking vitamin D, with or without calcium, does not reduce the risk of falling in elderly patients, regardless of baseline 25-hydroxyvitamin D levels, level of 25-hydroxyvitamin D achieved with treatment, duration of treatment, or residential status of the patients (91342). While a meta-analysis of 10 trials in nearly 6,000 patients shows that taking vitamin D 700-1000 IU daily with calcium 1000-2000 mg daily reduces the risk of falling in the elderly by 12% when compared with placebo or no treatment, a meta-analysis of 21 trials in nearly 52,000 patients shows that vitamin D alone is only associated with a reduced risk of falls in patients with baseline vitamin D levels of less than 50 nmol/L when compared with placebo or no treatment (107224). The 2018 US Preventative Services Task Force (USPSTF) guidelines for fall prevention acknowledges this research by recommending AGAINST vitamin D supplementation for fall prevention in community dwelling adults 65 years of age and older who do not have osteoporosis or vitamin D deficiency (95703). The reasons for the disparate study results may have to do with the way in which clinical trials have reported outcomes. Clinical trials assessing the effect of vitamin D on fall risk may report results as the number of patients who experience one or more falls, the total number of falls, or the rate of falls per individual. This can affect ultimate conclusions and, in some cases, can be misleading. For example, when studies report on only the total number of falls, it is unclear if vitamin D reduces the rate of falls across the study population, or if it only reduces falls in a small subset of patients. Also, analyses of research suggest that the size of the clinical study appears to affect the trial results. Most trials showing significant reductions in fall risk have been small and of short duration (91342,94132); whereas larger and longer-term studies tend to show no benefit (13073,84399).
Fetal and premature infant mortality. Taking vitamin D during pregnancy might reduce the risk of fetal or early infant death. Details: A meta-analysis of clinical research shows that vitamin D supplementation during pregnancy reduces the risk of intrauterine or neonatal death by 31% when compared with not supplementing with vitamin D. A sub-analysis shows that this benefit was limited to doses of up to 4000 IU daily (109055). However, a Cochrane review suggests that the evidence linking vitamin D supplementation to a lower risk of fetal or neonatal death is very uncertain (114587). Clinical practice guidelines from the Endocrine Society conditionally recommend, based on low certainty of evidence, empiric vitamin D supplementation from fortified foods, vitamin D supplements, or prenatal vitamin formulations that contain vitamin D during pregnancy to potentially lower the risk of intra-uterine and neonatal mortality, preeclampsia, preterm birth, and small for gestational age (SGA) birth. Empiric vitamin D supplementation is defined as supplementing with vitamin D above the Recommended Dietary Allowance without having tested serum vitamin D status (114502).
Fibromyalgia. A small clinical study suggests that vitamin D might improve pain in patients with fibromyalgia. Details: A small clinical study in fibromyalgia patients with low vitamin D levels shows that taking vitamin D3 (cholecalciferol) 1200-2400 IU daily seems to reduce pain, but not mood or quality of life, when compared with placebo (91349).
Food allergies. It is unclear if prenatal or infant oral vitamin D supplementation reduces the risk of developing food allergies. Details: A meta-analysis of two large clinical studies shows that prenatal or infant vitamin D supplementation does not reduce the risk of developing food allergies when compared with low-dose vitamin D or no intervention (108438).
Frailty. It is unclear if oral vitamin D is beneficial for the prevention or treatment of frailty in older adults. Details: Frailty involves a combination of muscle loss and weakness, with exhaustion and reduced ability for physical activity. Some observational research has found that low vitamin D status is associated with frailty occurrence. However, clinical research in community dwelling older adults shows that taking vitamin D as 1000 IU, 2000 IU, or 4000 IU daily for 24 months does not prevent frailty or attenuate the worsening of frailty when compared with low-dose vitamin D 200 IU daily. Baseline vitamin D status did not affect these findings. Also, a sub-analysis suggests that vitamin D 2000 IU might increase frailty; however, only a small number of participants were randomized to this dose (109046). Other clinical research in community dwelling adults at least 70 years of age shows that taking cholecalciferol 2000 IU daily for 3 years does not reduce the odds of becoming pre-frail or frail over 36 months when compared with placebo. However, when taken in combination with omega-3 fatty acids 1 gram daily and a home exercise program, the odds of becoming pre-frail is reduced by 39% (110829).
Generalized anxiety disorder (GAD). A small clinical study suggests that vitamin D may modestly improve anxiety in patients with GAD. Details: A small clinical study in patients with GAD shows that taking vitamin D 50,000 IU once weekly for 3 months, in addition to taking an antidepressant and an anxiolytic, moderately reduces anxiety scores when compared with taking these medications alone (103654).
Hematopoietic stem cell transplant (HSCT). It is unclear if oral vitamin D is beneficial for improving outcomes in patients receiving HSCT. Details: A small clinical study in patients who have undergone an autologous HSCT shows that taking calcitriol 0.25 mcg three times daily for 30 days can reduce the time to absolute lymphocyte count recovery, but does not affect time to recovery of absolute neutrophil and platelet counts, when compared with placebo (103665).
Hepatitis C. Low levels of vitamin D have been associated with an inadequate response to hepatitis C therapy. Adding vitamin D to standard therapy for hepatitis C may improve viral response, especially in specific genotypes. Details: A small clinical trial in patients with hepatitis C genotypes 2-3 receiving standard therapy with PEG-interferon and ribavirin shows that adding vitamin D 2000 IU daily for 24 weeks results in 95% of patients achieving undetectable levels of hepatitis C RNA, compared to only 77% of patients treated with standard therapy alone (98917). Another small clinical study in patients with hepatitis C genotype 1b receiving the same standard therapy shows that adding vitamin D 1000 IU daily for 16 weeks results in about 79% of patients achieving undetectable levels of hepatitis C RNA, compared to about 55% of patients treated with standard therapy alone. The TT genotype seems to be especially susceptible to vitamin D supplementation, while TG/GG genotype does not seem to be susceptible (98923).
HIV/AIDS. It is unclear if oral vitamin D is beneficial for improving bone mineral density (BMD) in children and young adults with HIV. Details: Vitamin D deficiency and hyperparathyroidism are common in children and young adults with HIV. A meta-analysis of two clinical trials in this population shows that taking cholecalciferol for 12 months does not improve spine BMD when compared with placebo. Also, an analysis of two clinical trials shows that taking doses of 1600 IU to 4000 IU daily does not improve spine BMD when compared with taking doses of 400-800 IU daily. However, taking higher dose vitamin D has a small beneficial effect on total BMD when compared with taking lower doses. There was no improvement on parathyroid hormone levels (110824). This meta-analysis is limited by the availability of small clinical trials, as well as the heterogeneous doses of vitamin D used in the included studies.
Hyperlipidemia. Although population research has found that higher vitamin D levels are associated with improved lipid levels, it is unclear if vitamin D supplementation is beneficial. Details: Population research has found that higher vitamin D levels are associated with lower low-density lipoprotein (LDL) cholesterol and triglyceride levels and higher high-density lipoprotein (HDL) cholesterol levels when compared with lower vitamin D levels (15630,98919). However, supplementation might not be beneficial. A meta-analysis of small clinical studies suggests that taking vitamin D as cholecalciferol, ergocalciferol, alfacalcidol, or calcitriol slightly increases LDL cholesterol, but does not affect total cholesterol, triglycerides, or HDL cholesterol, when compared with placebo (84642). The validity of these findings is limited by the variability in patient populations, vitamin D dose and formulation, and study duration. Also, none of the included studies were prospectively designed to test the effect of vitamin D on lipid levels. Another meta-analysis of clinical studies in a mixed population of healthy patients and patients with metabolic disease shows that taking vitamin D 1400-50,000 IU weekly with calcium 500-2000 mg daily results in very modest improvements in total cholesterol, triglyceride, and HDL cholesterol levels, but not LDL or very low-density lipoprotein (VLDL) cholesterol levels, when compared with placebo. Subgroup analyses suggest that effects are more pronounced in patients with metabolic disease (107227). The validity of these findings is limited by the heterogeneity of the included studies, which persisted throughout subgroup analyses.
Hyperthyroidism. Oral vitamin D has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Observational research suggests that serum vitamin D levels are decreased in patients with newly diagnosed Graves' disease. A small preliminary clinical trial in patients with newly diagnosed Graves' disease taking methimazole and low levels of selenium and vitamin D shows that taking vitamin D as cholecalciferol for 270 days, in combination with selenium for the first 180 days, modestly reduces levels of serum free thyroxine and improves quality of life when compared with no vitamin D or selenium. However, taking vitamin D and selenium did not affect levels of free triiodothyronine or positive thyroid stimulating hormone (TSH) receptor antibody (109049).
Hypothyroidism. It is unclear if oral vitamin D is beneficial in the treatment of subclinical hypothyroidism. Details: Preliminary clinical research in patients with vitamin D deficiency and subclinical hypothyroidism shows that taking vitamin D 50,000 IU weekly for 2-12 weeks decreases mean thyroid stimulating hormone levels by about 20% when compared with placebo, or by 3.55 mIU/L when compared to baseline (107213,113589).
Ichthyosis. It is unclear if oral vitamin D is beneficial in patients with inherited ichthyosis. Details: A small clinical study in patients with congenital non-syndromic ichthyosis shows that taking vitamin D 2000 IU daily for 24 weeks reduces the clinical severity of disease at 12 weeks, but not 24 weeks, when compared with baseline. When compared with patients taking acitretin 0.5 mg/kg daily, results were similar at both 12 and 24 weeks, but it is unclear if the improvement from baseline differed between groups (108441).
IgA vasculitis. It is unclear if oral alfacalcidol is beneficial in children with IgA vasculitis. Details: A clinical study in children with IgA vasculitis shows that taking alfacalcidol 0.25 mcg daily along with vitamin C, rutin, dipyridamole, cimetidine, calcium, and glucocorticoids for 4 weeks improves rates of recurrence and incidence of kidney damage when compared with those receiving the same regimen without alfacalcidol. Alfacalcidol also improves cellular immune function and reduces levels of inflammatory biomarkers (107212).
Irritable bowel syndrome (IBS). It is unclear if oral vitamin D is beneficial for IBS; the available research is conflicting. Details: Although some meta-analyses show that taking vitamin D is moderately more effective than placebo for improving IBS symptom severity and quality of life, other analyses disagree. Doses of vitamin D have included 50,000 IU weekly or every 2 weeks or 2000-4000 IU daily for up to 6 months (109041,109054,109057). The reasons for these discrepancies might be attributed to the inclusion criteria related to the individual trials, the small sample sizes, and varied dosing strategies used in the available research.
Kidney transplant. It is unclear if oral cholecalciferol is beneficial for improving allograft function or preventing non-skeletal complications in kidney transplant recipients. Details: Following a kidney transplant, patients are at increased risk of vitamin D insufficiency and related outcomes. A large clinical trial shows that taking a high dose of cholecalciferol for 2 years does not reduce the composite risk of developing type 2 diabetes, major cardiovascular events, or cancer, or death when compared to taking a lower dose. The high and low doses of vitamin D were 100,000 IU or 12,000 IU, respectively, every 2 weeks for 2 months, followed by monthly doses for the next 22 months (110830). The effect of a high dose of vitamin D on these outcomes individually is not clear. However, taking vitamin D does not seem to improve allograft function. A clinical study in kidney transplant recipients shows that taking cholecalciferol 4000 IU daily, beginning 1-month posttransplant and continuing for 11 months, has no effect on allograft function when compared with placebo (108425).
Kidney transplant-related bone loss. Oral vitamin D might be beneficial for preventing bone loss associated with kidney transplantation. Details: A large clinical trial shows that taking a high dose of cholecalciferol for 2 years modestly reduces the odds of a fracture by 76% when compared to taking a lower dose. The high and low doses of vitamin D were 100,000 IU or 12,000 IU, respectively, every 2 weeks for 2 months, followed by monthly doses for the next 22 months (110830). A prespecified secondary analysis of a clinical study in patients at 1-month post-kidney transplant from a living donor in Japan shows that taking vitamin D (cholecalciferol) 4000 IU daily for months 1-12 posttransplant reduces whole blood parathyroid hormone levels by 15%, but does not alter levels of tartrate-resistant acid phosphatase 5-b or bone-specific alkaline phosphatase, when compared with placebo. The greatest effects on parathyroid hormone levels are observed in those with more severe vitamin D deficiency, hypocalcemia, and more preserved kidney function. Vitamin D supplementation also attenuates changes in bone mineral density (BMD) at the lumbar spine, but not the distal radius, from prior to transplant. Patients taking vitamin D had a loss of only 0.2%, compared with a loss of 2% in those receiving placebo. The greatest effects are observed in those with osteoporosis or osteopenia (107220). Conversely, a small clinical trial shows that taking calcitriol (1,25-dihydroxyvitamin D3) 0.25 mcg daily in combination with calcium carbonate 500 mg daily does not decrease bone loss associated with kidney transplantation. However, calcitriol might reduce osteoclast suppression, help maintain trabecular bone volume and wall thickness, and improve axial BMD (4823).
Impaired glucose tolerance (prediabetes). Taking vitamin D might slow prediabetes progression to diabetes in people with low baseline levels of vitamin D or in people achieving high levels of vitamin D following supplementation. It is unclear if vitamin D supplementation is beneficial in people with prediabetes and sufficient vitamin D levels. Details: Observational research has found that low vitamin D levels are linked with a higher risk of prediabetes and higher dietary vitamin D is linked with a lower chance of developing diabetes (84594,103669). Meta-analyses and individual clinical studies in patients with prediabetes and unclear or sufficient vitamin D levels show that vitamin D supplementation might improve some glycemic indices, but does not seem to prevent progression of prediabetes to diabetes (84594,91347,99769,108421). However, a more recent meta-analysis of 3 clinical studies designed to evaluate the preventative effects of oral vitamin D shows that taking it in the form of cholecalciferol 4000 IU daily or 20,000 IU weekly or eldecalcitol 0.75 mcg daily reduces the risk of developing diabetes with an absolute risk reduction of 3.3% over 3 years when compared with placebo. However, the actual risk reduction is highly dependent on vitamin D status. Patients achieving the highest serum vitamin D levels have absolute 3-year risk reductions of 11.4% to 18.1% (110810). In patients with vitamin D deficiency and prediabetes, vitamin D might improve beta-cell function, suggesting reduced disease progression (99768,107210). One clinical study in adults with vitamin D deficiency shows that taking vitamin D 50,000 IU weekly for 3 months, and then monthly for 3 months, modestly improves insulin resistance and beta-cell function as measured by the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), but does not affect fasting or postprandial glucose levels when compared with placebo (99768). Further, a meta-analysis of randomized controlled trials in patients with vitamin D deficiency and prediabetes shows that oral vitamin D at a median dose of 50,000 IU weekly for 26 weeks modestly improves fasting blood glucose and some markers of islet function, but not postprandial blood glucose or glycated hemoglobin (HbA1c) levels, when compared with control. Additionally, a significantly greater proportion of patients receiving vitamin D supplementation regressed from prediabetes to normal glucose status (107210). A meta-analysis of clinical studies in overweight or obese children and adolescents shows that high doses of vitamin D, 4000 IU daily or higher for 12-52 weeks, reduce HOMA-IR and C-reactive protein levels, but do not affect body weight, cholesterol, or parathyroid hormone (113596). A study in females with vitamin D deficiency and prediabetes shows that taking vitamin D 60,000 IU weekly for 8 weeks, followed by a maintenance dose of 200 IU daily, has no effect on the incidence of type 2 diabetes at 2 years (107211). Clinical practice guidelines from the Endocrine Society conditionally recommend, with moderate certainty of evidence, empiric vitamin D supplementation in addition to lifestyle modification for adults with high-risk prediabetes to reduce the risk of progression to diabetes. Empiric vitamin D supplementation is defined as vitamin D from supplements or fortified food above the Recommended Dietary Allowance without having tested serum vitamin D status (114502).
Infant development. It is unclear if giving oral vitamin D in doses above the recommended dietary allowance during infancy is beneficial for improving neurodevelopment. It is also unclear if oral vitamin D during pregnancy is beneficial for improving cognitive development in the offspring. Details: Clinical research shows that giving vitamin D 1200 IU daily to healthy term infants of Northern European ethnicity starting at 2 weeks of age does not improve measures of neurodevelopment at 2 years of age when compared with giving the standard dose of vitamin D 400 IU (106121). Overall, the evidence from population research is mixed as to whether vitamin D status during gestation is associated with infant developmental outcomes. However, some population research has found that increased vitamin D status during pregnancy is associated with improved anthropomorphic and neurodevelopmental outcomes (104621,105724). Two meta-analyses of observational research show that low vitamin D status during pregnancy is associated with reduced head circumference and cognitive development scores, and higher odds of the offspring developing autism and attention deficit hyperactivity disorder (105724,105725). However, one meta-analysis suggests these risks may be limited to those with very low vitamin D status (serum level < 12 ng/mL) (105724). Multiple meta-analyses show that vitamin D status during pregnancy does not appear to affect motor development (105724,105725). In one observational study, plasma vitamin D concentrations in the second trimester of pregnancy was associated with increased IQ scores in the offspring at age 4-6 years. Each 10 ng/mL increase in vitamin D levels was associated with a 1.17-point increase in IQ (104621). In contrast, clinical research shows that taking vitamin D3 2800 IU daily during the third trimester does not improve neurodevelopmental outcomes in the first 6 years of life when compared to taking lower doses of 400 IU daily (104623).
Infertility. It is unclear if oral or intramuscular vitamin D is beneficial in females with infertility. Details: Observational research in females undergoing in vitro fertilization suggests no association between dietary vitamin D intake and oocyte quality, successful embryo transfer, clinical pregnancy rate, or term pregnancy rate (112097). Additionally, a meta-analysis of clinical research in females with infertility shows that, although there was no effect of taking vitamin D on implantation rate or miscarriage, taking vitamin D increases the odds of clinical pregnancy by 49% when compared with placebo. However, sub-analyses of clinical and observational research found that benefits on clinical pregnancy rates were limited to populations with vitamin D insufficiency, but not vitamin D deficiency, and for doses between 1000 to 10,000 IU daily for 30-90 days (110818). Most studies included in the analysis used oral vitamin D; however, intramuscular vitamin D was used in one cohort study. A smaller meta-analysis of clinical studies in females with infertility and vitamin D insufficiency undergoing IVF shows that taking vitamin D increases the rate of chemical pregnancy by 50%, but has no effect on the clinical pregnancy rate (108432).
Lichen planus. It is unclear if oral vitamin D is beneficial for lichen planus. Details: A small clinical study in patients with oral lichen planus and vitamin D deficiency or insufficiency shows that taking vitamin D 60,000 IU weekly in combination with systemic steroids for 1 month reduces pain severity and improves healing of lesions when compared with systemic steroids alone (114586). The validity of the study is limited by the lack of a placebo.
Low birth weight. It is unclear if oral vitamin D can reduce the risk for low birth weight; the available evidence is conflicting. Details: A meta-analysis of observational research has found that a very low vitamin D status (serum level <12 ng/mL) during pregnancy is associated with lower birth weight and increased odds of SGA births. However, these risks have not been demonstrated in those with less severe vitamin D deficiency (serum level <20 ng/mL) (105724). Most research also shows that vitamin D supplementation during pregnancy reduces the risk of low birth weight. A meta-analysis of three clinical trials shows that supplementation with vitamin D 800-1000 IU daily starting between 27 and 32 weeks' gestation, or 200,000 IU administered as a single dose or in two divided doses during the seventh and eighth month of pregnancy, reduces the risk of delivering a low birth weight infant by 60% (84659). Other meta-analyses of clinical research show that supplementation with vitamin D during pregnancy results in a 31% to 60% reduced risk of low birth weight and a 103 gram greater average birth weight when compared with placebo or no intervention (99766,114587). However, some meta-analyses show that vitamin D supplementation during pregnancy does not reduce the risk of low birth weight when compared with no supplementation (95910,109055). One meta-analysis that included studies that did not directly measure birth weight shows no effect of vitamin D supplementation during pregnancy on the rate of low birth weight, despite showing an increase in overall birth weight of about 58 grams (95910).
Lung cancer. It is unclear if oral vitamin D prevents lung cancer or improves lung cancer prognosis. Details: A small meta-analysis of randomized controlled trials and observational research has found that high intake of vitamin D is associated with a 10% reduction in the risk of developing lung cancer when compared with low vitamin D intake. In terms of prognosis, high vitamin D intake is associated with improvements in both overall survival and relapse-free survival (107217).
Male infertility. It is unclear if oral cholecalciferol is beneficial in males with infertility. Details: A small clinical study in males with infertility shows that taking cholecalciferol 2500 IU daily for 6 months modestly improves progressive sperm motility, sperm concentration, and sperm morphology when compared with baseline (108427). The validity of these findings is limited by the lack of a comparator group.
Melanoma. It is unclear if oral vitamin D is beneficial in patients with melanoma. Details: A meta-analysis of 14 observational studies suggests that vitamin D deficiency is associated with a 45% greater risk of melanoma when compared with normal vitamin D levels (112027). However, a small clinical study in patients with newly resected stage II melanoma shows that taking vitamin D3 100,000 IU every 50 days for 3 years does not improve disease-free survival when compared with placebo. Most patients in this study had vitamin D deficiency or insufficiency at baseline (106113).
Metabolic syndrome. It is unclear if oral vitamin D is beneficial for preventing or treating metabolic syndrome. Details: In patients with metabolic syndrome, clinical research shows that taking vitamin D 50,000 IU weekly for 16 weeks does not affect most metabolic or anthropometric factors when compared with placebo, although there was a modest decrease in triglyceride levels (106123). However, almost all of the individuals in this study were vitamin D deficient or insufficient, and many remained in that category even after supplementation. It is unclear if vitamin D supplementation is beneficial in vitamin D sufficient patients with metabolic syndrome. There is conflicting evidence about the association between vitamin D and metabolic syndrome (14265,16713,98234). Some population research has found that higher vitamin D levels are associated with a lower risk of metabolic syndrome, while other research found no association (14265,16713). Furthermore, a small clinical trial in patients with metabolic syndrome shows that taking vitamin D 20,000 IU or 40,000 IU weekly for 8 weeks does not affect metabolic risk factors when compared with placebo (98234).
Migraine headache. It is unclear if oral vitamin D reduces the frequency of migraine. Details: A meta-analysis of three small high-quality clinical studies in patients with migraine shows that taking vitamin D 2000 or 4000 IU daily for 12-24 weeks or 500,000 IU weekly for 2 months reduces the frequency of migraines by 2-3 attacks monthly when compared with usual care or placebo (108439).
Miscarriage. Oral vitamin D has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in pregnant adults with threatened miscarriage between the 6th and 13th week of gestation shows that taking a specific combination product (DAV HA, Lo.Li pharma s.r.l) containing vitamin D 50 mcg, alpha-lipoic acid, hyaluronic acid, magnesium, and vitamin B6 daily in combination with conventional treatment of vaginal progesterone over 2 weeks of observation results in a faster resorption of the subchorionic hematoma and faster decrease of patient-reported vaginal bleeding, abdominal pain, and uterine contractions when compared with vaginal progesterone alone (113893). It is unclear if these effects are due to vitamin D, other ingredients, or the combination. Additionally, the validity of these findings is limited by the lack of a placebo for the control group.
Multiple sclerosis (MS). Although vitamin D supplementation has been linked with a lower risk of developing MS, taking oral vitamin D supplements does not seem to reduce MS relapses. Details: Vitamin D deficiency appears to be linked to the risk of MS development and progression. Population research suggests that long-term supplementation with vitamin D 400 IU is associated with a 40% lower risk of MS in females. The effect seems to be dose-dependent. Consumption of at least 400 IU daily, mainly in the form of a multivitamin supplement, appears to have the greatest protective effect (11356). Additional population research in over 7 million people suggests that higher levels of calcifediol are associated with a lower risk of developing MS. In white adults, for every 20 ng/mL increase in vitamin D levels, there appears to be a 41% decrease in MS risk. However, this was not found in black and Hispanic adults (15159). Vitamin D supplementation has also been examined in patients with MS. Population research suggests that taking vitamin D supplements and the maintenance of optimal blood levels of vitamin D are associated with a reduction in the development of new areas of demyelination detected by magnetic resonance imaging (MRI) over 24 months. However, there are no correlations between vitamin D consumption or vitamin D blood levels and clinical outcomes (110816). Also, vitamin D supplementation does not seem to impact MS relapses or most symptoms in patients with MS. Meta-analyses of preliminary clinical research show that vitamin D supplementation does not affect the rate of MS relapses, overall symptoms, disability scores, or the number of MS nerve lesions detected by MRI, regardless whether the vitamin D was low-dose or high-dose (98192,98914,106119,113586). However, one meta-analysis of 6 small clinical studies shows that taking vitamin D for 8-96 weeks slightly improves fatigue scores when compared with placebo (112024). These analyses are limited by the small size and heterogeneity of most of the included studies and variability in dosing and duration of vitamin D regimens.
Muscle strength. It is unclear if oral vitamin D improves muscle strength in middle aged or older adults with low or sufficient levels of vitamin D. The available research is conflicting. Details: Clinical research in healthy older adults who are not deficient in vitamin D shows that oral vitamin D3 (cholecalciferol) supplementation, with 800 IU, 1000 IU, or 2000 IU daily or 50,000 IU monthly, alone or in combination with a resistance training program, does not increase muscle strength when compared with placebo (11814,104619,108429). In patients 40-80 years of age with low vitamin D levels, taking vitamin D3 100,000 IU (2500 mcg) once, followed by 20,000 IU (500 mcg) weekly for 4 months, does not improve muscle strength when compared with placebo (103658). Similarly, meta-analyses of clinical research show that vitamin D does not increase grip strength, muscle mass, global muscle strength, or back extensor strength when compared with control (91341,113595). However, some research has found some benefit with the use of vitamin D supplements. One meta-analysis shows that taking vitamin D increases grip strength after menopause when compared with placebo or low-dose vitamin D, although a sub-analysis shows that beneficial effects are limited to individuals aged 60-69 years, when vitamin D is taken without calcium, when baseline vitamin D levels are at least 30 ng/mL, or when the treatment consists of the vitamin D analog alfacalcidol. This suggests heterogeneity between studies (109048). Another meta-analysis in elderly adults shows that taking vitamin D as calcifediol 10-30 mcg daily for a median of 24 weeks modestly improves hand grip strength and leg extension, but not leg flexion, when compared with baseline (109042). Also, some individual clinical research in older adults with low levels of vitamin D at baseline shows that taking vitamin D3 800 IU daily or vitamin D2 (ergocalciferol) 1000 IU daily for 12 months in combination with calcium 1000 mg daily modestly improves lower extremity or hip strength by 8% to 23% when compared with calcium alone (38915,84530).
Myalgia. It is unclear if oral vitamin D is beneficial for reducing myalgia associated with obesity. Details: Preliminary clinical research in obese individuals with vitamin D deficiency who are on a low-calorie diet shows that taking vitamin D 50,000 IU weekly, alone or in combination with an aerobic exercise program three times weekly for 12 weeks, modestly reduces muscle pain when compared with only aerobic exercise three times weekly (106118).
Myelodysplastic syndromes. It is unclear if oral vitamin D is beneficial for patients with myelodysplastic syndromes. Details: A small observational study in patients with myelodysplastic syndromes has found that taking calcitriol or calcifediol orally is associated with slowed disease progression (11825).
Nonalcoholic fatty liver disease (NAFLD). It is unclear if oral or intramuscular vitamin D is beneficial in children or adults with NAFLD. Details: Although findings from individual research are mixed, one meta-analysis of mainly small clinical trials in patients with NAFLD shows that vitamin D modestly improves insulin resistance and serum alanine aminotransferase (ALT) levels, with no effect on serum aspartate aminotransferase (AST) levels. Most studies included in the analysis used oral vitamin D 1000 IU daily or 50,000 IU weekly or biweekly for 3-6 months and compared with placebo; however, one study used a single intramuscular injection of vitamin D 600,000 IU compared with lifestyle modifications (109056). Vitamin D has also been evaluated in combination with fish oil. A clinical study in adults with NAFLD shows that taking oral vitamin D3 1680 IU daily in combination with fish oil or fish oil alone for 3 months improves serum ALT levels similarly to a control group (107186). Vitamin D has also been evaluated for use in children with NAFLD. One clinical study in children with obesity and biopsy-proven NAFLD shows that taking oral vitamin D3 2000 IU daily for 6 months with a hypocaloric diet improves liver histopathology in terms of steatosis, lobular inflammation, and NAFLD activity score at 6 months, but not hepatocyte ballooning or fibrosis, when compared with baseline. These improvements were not seen in the group receiving placebo with a hypocaloric diet, but it is unclear if the improvement from baseline differed between groups (107222).
Nonmelanoma skin cancer. It is unclear if oral vitamin D is beneficial for preventing keratinocyte carcinomas. Details: In middle aged and older adults recently diagnosed with a colorectal adenoma, clinical research shows that taking vitamin D3 1000 IU daily for 3-5 years does not reduce the incidence of keratinocyte cancer when compared with placebo over a median of 8 years. A sub-group analysis shows that taking vitamin D3 with calcium 1200 mg daily as calcium carbonate reduces the risk of invasive cutaneous squamous cell carcinoma by a moderate amount, but has no effect on the risk of basal cell carcinoma. Vitamin D taken alone has no effect on the risk for either type of cancer (104622).
Obesity. The evidence for the use of oral vitamin D in obesity is conflicting and unclear. Details: Population research has found that people with lower vitamin D levels are significantly more likely to be obese when compared to people with higher vitamin D levels (15630). Also, a large-scale, high-quality clinical trial in postmenopausal adults taking calcium 1000 mg plus vitamin D3 (cholecalciferol) 400 IU daily for 3 years shows that these patients are more likely to lose weight and maintain their weight when compared with those taking placebo. This beneficial effect is mainly seen in females who have inadequate intake of calcium, less than 1200 mg/day, before starting a calcium supplement (15604). However, other evidence suggests that vitamin D alone does not improve weight loss. One clinical trial shows that taking vitamin D3 2000 IU/day without calcium for 12 months does not increase weight loss when compared with placebo in overweight and obese postmenopausal adults who are deficient in vitamin D at baseline (91345).
Orthostatic hypotension. It is unclear if oral vitamin D is beneficial for prevention of orthostatic hypotension. Details: A secondary analysis of a clinical study in older patients with vitamin D insufficiency who are at an increased risk for falls shows that taking vitamin D 1000-4000 IU daily for up to 2 years has no effect on the risk of orthostatic hypotension or orthostatic symptoms when compared with those receiving vitamin D 200 IU daily (107223).
Osteoarthritis. It is unclear if oral vitamin D is beneficial for osteoarthritis. Details: The evidence for the use of vitamin D in osteoarthritis is conflicting. Some clinical research shows that taking vitamin D3 (cholecalciferol) 2000 IU daily, or at a higher dose to reach serum vitamin D levels over 36 ng/mL, for 2 years does not reduce knee pain or loss of cartilage when compared with placebo in patients with symptomatic osteoarthritis (84688). However, another clinical study shows that taking vitamin D3 daily for 10 days and then vitamin D3 60,000 IU monthly for 12 months modestly reduces pain and improves function when compared with placebo in patients with osteoarthritis and vitamin D insufficiency (98199). It is possible that higher doses of vitamin D have an effect on osteoarthritis, while lower doses do not. Due to this conflicting and low-quality evidence, the American College of Rheumatology (ACR) recommends against the use of vitamin D for any form of osteoarthritis (102114).
Otitis media. It is unclear if oral vitamin D is beneficial in patients with otitis media. Details: The relationship between vitamin D status and otitis media is unclear. Population research has found that having otitis media is associated with lower blood levels of vitamin D; however, lower vitamin D levels were not associated with greater risk of otitis media (98194).
Overactive bladder. It is unclear if oral vitamin D is beneficial for overactive bladder. Details: A large clinical trial in older males shows that taking vitamin D3 (cholecalciferol) 2000 IU daily for 5 years does not reduce the odds of weekly overactive bladder when compared with placebo. In males with low serum vitamin D, taking vitamin D reduces the odds of overactive bladder at 5 years by 49%, including 34% reduced odds of overactive bladder with urinary incontinence and 81% reduced odds of overactive bladder without incontinence. However, urinary incontinence while sleeping or napping was increased (109738).
Overall mortality. Taking oral vitamin D alone does not seem to reduce mortality; however, there is some evidence that taking certain forms of vitamin D with calcium might have a modest benefit. Details: While higher vitamin D levels have been associated with a small reduction in mortality when compared with lower vitamin D levels (98187), clinical research shows that taking vitamin D does not reduce the risk of mortality. A comprehensive meta-analysis shows that vitamin D supplementation alone does not reduce all-cause mortality when compared to control (100900). However, giving vitamin D with calcium may modestly reduce the risk of mortality. Meta-analyses show a 4% to 9% reduced risk of mortality when trials of vitamin D alone and vitamin D with calcium are pooled together (16102,97296,98186,112022). Finally, some research suggests that the type of vitamin D supplementation might influence the results. A meta-analysis of clinical research found that vitamin D3 (cholecalciferol) with or without calcium reduces mortality risk by 6%, while alfacalcidol, calcitriol, and vitamin D2 (ergocalciferol) do not have benefit (84595,98186). Other clinical research suggests that vitamin D supplementation in older adults may reduce the risk of all-cause mortality by about 4%, with an estimated effect size of 6 fewer deaths per 1000 individuals. This finding informed the 2024 Endocrine Society Clinical Practice Guidelines on vitamin D for the prevention of disease in the general population. The Endocrine Society conditionally recommends, with moderate certainty of evidence, empiric vitamin D supplementation from fortified foods or vitamin D-containing supplements in the general population aged 75 years and older to potentially lower the risk of mortality. Empiric vitamin D is defined as vitamin D above the Recommended Dietary Allowance without having tested serum vitamin D status. For empiric supplementation and for those who have indications for vitamin D treatment or supplementation, daily lower-dose versus intermittent higher doses was suggested (114502).
Pain (chronic). It is unclear if oral vitamin D is beneficial for chronic pain. Details: A meta-analysis of clinical research in patients with chronic pain shows that taking vitamin D for 1-24 months produces a 43% greater decrease in pain score when compared with placebo. However, the final follow-up pain score is similar for both groups (96402). The effect of vitamin D on pain based on pain-related diagnosis, vitamin D status, or dose is unknown.
Parkinson disease. It is unclear if oral vitamin D is beneficial for this condition. Details: Population research found that higher levels of vitamin D are associated with milder Parkinson disease symptoms, while deficiency is associated with increased risk of Parkinson disease (97000,99772). One small study shows that taking vitamin D3 (cholecalciferol) 1200 IU daily for one year might modestly slow the progression of Parkinson disease based on the Hoehn and Yars staging criteria. However, there was no improvement in disease severity according to the more widely used Unified Parkinson Disease Rating Stage (UPDRS). The UPDRS includes measures of activities of daily living and non-motor symptoms. Vitamin D had no effect on most quality of life measures (95915).
Periodontitis. It is unclear if oral vitamin D is beneficial for periodontal disease. Details: A meta-analysis of mostly observational research suggests that vitamin D levels are not associated with an increased or decreased risk of periodontitis (112026). Other population research suggests that higher blood levels of vitamin D may be associated with a reduced risk of periodontal disease in adults 50 years of age or older. However, this association was not found for adults younger than 50 years (15634).
Physical performance. It is unclear if oral vitamin D improves muscle strength in elderly adults. Details: Some clinical research in healthy older adults who are not deficient in vitamin D shows that oral vitamin D3 (cholecalciferol) supplementation, with 800 IU, 1000 IU, or 2000 IU daily or 50,000 IU monthly, alone or in combination with a resistance training program, does not improve physical performance when compared with placebo (11814,104619,108429). Also, results from one meta-analysis of clinical research in postmenopausal females with low levels of vitamin D shows that taking vitamin D does not improve the timed up and go test when compared with placebo or low-dose vitamin D (109048). One meta-analysis that included studies specifically evaluating the use of calcifediol in older adults shows a large benefit on gait speed; however, only one study included in the analysis used this endpoint and other measures of physical performance were not affected (109042).
Pneumonia. High-dose oral vitamin D does not reduce pneumonia severity in children. Details: Although vitamin D supplementation might prevent respiratory tract infections in children, it might not prevent recurrent pneumonia. A small clinical study in children under 5 years of age with recurrent pneumonia and variable vitamin D blood levels shows that taking vitamin D 300,000 IU quarterly for 1 year does not reduce respiratory infections, severity of pneumonia, hospital admissions, or disease complications when compared with placebo (103667). However, it's unknown if vitamin D supplementation using lower and more frequent doses, or supplementation in patients with vitamin D deficiency, might be beneficial. Some observational research has found that having vitamin D deficiency is linked to a higher risk for developing community-acquired pneumonia (CAP) (102118). For information on other respiratory infections, refer to the Respiratory Tract Infection discussion.
Polycystic ovary syndrome (PCOS). It is unclear if vitamin D improves pregnancy outcomes and symptoms in patients with PCOS. Details: Observational research in adults with infertility, PCOS, and insulin resistance suggests that normal vitamin D levels are associated with better embryo quality and increased pregnancy rate when compared with vitamin D deficiency or insufficiency (100834). It is unclear if supplementation with vitamin D improves pregnancy rates in patients with PCOS. A meta-analysis of clinical research shows that taking vitamin D 400-12,000 IU daily for 2-6 months improves follicular development when compared with placebo. Taking vitamin D in combination with metformin 1500 mg daily also appears to increase the number of regular menstrual cycles by 85% when compared with metformin alone, but without an effect on follicular development (96404). A meta-analysis of 9 studies also shows that combining vitamin D with metformin improves menstrual cycle regulation and reduces homeostatic model assessment for insulin resistance (HOMA-IR), body mass index, and testosterone levels when compared with metformin alone (113594). Vitamin D alone does not appear to improve menstrual cycle regularity. A meta-analysis of several mostly low quality clinical studies in patients with PCOS and vitamin D deficiency at baseline shows that taking intramuscular or oral vitamin D 200-10,000 IU daily for up to 24 weeks in addition to fertility treatment improves pregnancy rates and reduces premature miscarriage and premature delivery, but does not impact the incidence of pregnancy complications including gestational hypertension or gestational diabetes mellitus, when compared with control. This analysis also suggests vitamin D supplementation improves certain IVF-related outcomes including ovulation rate, fertilization rate, and number of mature oocytes (112787). The effects of vitamin D on the metabolic profile of patients with PCOS have been evaluated. A small clinical study in patients with PCOS and vitamin D deficiency or insufficiency shows that taking vitamin D 2000 IU daily in combination with diet and exercise for 12 weeks reduces insulin resistance, body mass index, waist to hip ratio, serum triglycerides, and total and low-density lipoprotein cholesterol when compared with diet and exercise alone (114580). The interpretation of these results is limited by the lack of a placebo.
Post-stroke fatigue. It is unclear if oral vitamin D is beneficial for post-stroke fatigue. Details: A retrospective study in patients with post-stroke fatigue and vitamin D deficiency suggests that vitamin D (cholecalciferol) 600 IU daily is associated with improvements in fatigue severity at months 1 and 3 when compared with control. Neurologic disability also showed improvement at 3 months, but not at 1 month, when compared with control. It is unclear if improvements from baseline differed between groups (107225).
Pre-eclampsia. It is unclear if oral vitamin D during pregnancy is beneficial for the prevention or treatment of pre-eclampsia. Details: While some clinical research suggests that taking vitamin D during pregnancy does not reduce the risk of pre-eclampsia (113585,114587), clinical practice guidelines from the Endocrine Society conditionally recommend, based on low certainty of evidence, empiric vitamin D supplementation from daily intake of fortified foods, vitamin D supplements, or prenatal vitamin formulations that contain vitamin D during pregnancy to potentially lower the risk of preeclampsia, intra-uterine mortality, preterm birth, small for gestational age (SGA) birth, and neonatal mortality. Empiric vitamin D supplementation is defined as supplementing with vitamin D above the Recommended Dietary Allowance without having tested serum vitamin D status (114502).
Precocious puberty. It is unclear if oral vitamin D is beneficial for the prevention or treatment of precocious puberty. Details: A meta-analysis of 43 mostly observational studies from China suggests that vitamin D deficiency or insufficiency is associated with 2.25-fold greater odds of precocious puberty when compared with normal vitamin D levels. Taking vitamin D 200-1000 IU daily for 3-12 months along with a gonadotropic-releasing hormone analog (GnRHa) is associated with lower luteinizing hormone, follicle-stimulating hormone, and estradiol levels and reduced bone age when compared with GnRHa therapy alone (112019). Another meta-analysis of 15 studies, mainly from China and with high heterogeneity and publication bias, suggests that there is a negative correlation between serum 25-hydroxy-vitamin D concentrations and precocious puberty, and that vitamin D deficiency increases the risk of precocious puberty by about 53% (113578).
Pregnancy-induced hypertension. It is unclear if oral vitamin D is beneficial for patients with gestational hypertension. Details: Meta-analyses of two low-quality clinical trials show that vitamin D supplementation during pregnancy does not reduce the risk for gestational hypertension when compared with control (95910,114587).
Prematurity. It is unclear if taking vitamin D during pregnancy prevents respiratory complications in preterm neonates. Details: A large clinical study in pregnant patients with gestational age less than 34 weeks and at risk of preterm delivery shows that a single intramuscular injection of vitamin D 50,000 IU within 72 hours before delivery decreases the risk of respiratory distress syndrome treated by surfactant in the neonate by about 2.25-fold and increases the 5th minute APGAR scores, but not 1st minute APGAR scores, gestational age, neonatal intensive care unit admission, length of hospital stay, or delivery method, when compared with no treatment (114581).
Premenstrual syndrome (PMS). It is unclear if oral vitamin D is beneficial in patients with PMS. Details: Observational research has found that increasing dietary intake of vitamin D above 706 IU daily is linked to a reduced risk of developing PMS when compared with consuming 112 IU daily (13094). Furthermore, a clinical study shows that taking vitamin D 400 IU daily in combination with calcium 1000 mg daily can decrease the severity of PMS symptoms (16869). Another clinical study in adolescent females with PMS shows that taking vitamin D3 50,000 IU weekly for 9 weeks modestly reduces PMS symptoms when compared to baseline (98912). A small clinical study in young adults with PMS and vitamin D deficiency shows that taking vitamin D 50,000 IU every 2 weeks for 16 weeks reduces psychological symptom scores by 54% and physical symptom scores by 39% when compared with placebo (113582).
Preterm labor. It is unclear if oral vitamin D is beneficial for preterm labor. Details: Vitamin D deficiency, defined as serum levels less than 20 ng/mL, during pregnancy has been associated with a 25% greater risk of preterm birth (95911). The risk seems to be especially prominent in those with darker colored skin (103662). However, meta-analyses of clinical research show that vitamin D supplementation during pregnancy does not reduce the risk of a preterm birth when compared with no supplementation with vitamin D (84659,95910,109055,114587). The effect vitamin D specifically in vitamin D-deficient patients is still unclear. Some small, heterogeneous, and low-quality studies show that vitamin D supplementation might reduce the rate of preterm birth in vitamin D-deficient patients (84659,95910). Additional studies are needed to determine the effect of vitamin D supplementation on the risk of preterm birth. Clinical practice guidelines from the Endocrine Society conditionally recommend, based on low certainty of evidence, empiric vitamin D supplementation from daily intake of fortified foods, vitamin D supplements, or prenatal vitamin formulations that contain vitamin D during pregnancy to potentially lower the risk of preterm birth, small for gestational age (SGA) birth, preeclampsia, intra-uterine mortality, and neonatal mortality. Empiric vitamin D supplementation iss defined as supplementing with vitamin D above the Recommended Dietary Allowance without having tested serum vitamin D status (114502).
Rheumatoid arthritis (RA). Small clinical studies suggest that oral vitamin D may not improve symptoms in patients with RA. Details: Population research has found that higher intake of vitamin D from foods or supplements is associated with a lower risk of developing RA (12206,98200). However, a meta-analysis of two small clinical trials shows that vitamin D supplementation does not reduce pain or recurrence of RA when compared with placebo (98190).
Rhinosinusitis. Oral vitamin D has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in patients over 12 years of age with chronic sinusitis shows that taking 1 or 2 sachets of a specific combination product (Flogostop Forte, Humana Italia) containing vitamin D 600 IU, black currant, Boswellia serrata, and bromelain along with a nasal corticosteroid daily for 15-30 days reduces symptoms of nasal hyperemia and rhinorrhea when compared with corticosteroid nasal spray alone (111501). It is unclear if these findings are due to vitamin D, other ingredients, or the combination.
Sarcopenia. It is unclear if oral vitamin D is beneficial in older adults with sarcopenia. Details: A meta-analysis of randomized trials in older adults with sarcopenia shows that taking vitamin D3 (cholecalciferol) 100-800 IU daily, with protein 10-44 grams daily or amino acids 2.5-6 grams daily, for 2-6 months moderately improves muscle strength, but not muscle mass or walking speed, when compared with placebo (105727). The validity of this study is limited by high heterogeneity and an unreported baseline vitamin D status. Similarly, a small network meta-analysis of randomized trials shows that taking vitamin D 500-1600 IU daily or 2500-5000 IU weekly with protein 20-80 grams daily or amino acids 3-32 grams daily with and without exercise for 3-18 months increases hand grip strength and shortens time to chair-stand, respectively, but not gait speed or lower-limb mass when compared with usual care (107221). It is unclear if these effects are due to vitamin D, protein/amino acid supplementation, exercise, or the combinations.
Schizophrenia. It is unclear if oral vitamin D is beneficial for schizophrenia. Details: Based on preliminary clinical evidence, Guidelines from The World Federation of Societies of Biological Psychiatry (WFSBP) and Canadian Network for Mood and Anxiety Treatments (CANMAT) Taskforce state that vitamin D in doses of 1500 to 4000 IU daily is not recommended for adjunctive use in patients with schizophrenia (110318). A moderate-sized clinical study in patients with schizophrenia shows that taking a specific combination product (BioZenD, Tak Gen Zist Pharmaceutical Company) containing vitamin D 400 IU in combination with a blend of probiotics (Lactobacillus acidophilus, Lacticaseibacillus rhamnosus, Limosilactobacillus reuteri, Lacticaseibacillus paracasei, Bifidobacterium longum, Bacillus coagulans) 2 x 10⁹ CFU daily for 12 weeks improves cognitive function scores but does not improve the severity of positive and negative schizophrenia symptoms when compared with placebo (114582). It is unclear if this effect is due to vitamin D, the probiotics, or the combination.
Sciatica. Oral vitamin D has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary research in adults up to 45 years of age with discogenic sciatica shows that taking cholecalciferol 800 IU with alpha-lipoic acid, acetyl-L-carnitine, and resveratrol daily for 30 days, in combination with a 20-session rehabilitation protocol, improves pain, disability, and quality of life when compared with the supplements alone or the rehabilitation protocol alone (112933).
Seasonal affective disorder (SAD). One small study suggests that a large dose of oral vitamin D can improve symptoms of SAD. Details: A small clinical study in patients with SAD suggests that a single dose of vitamin D2 (ergocalciferol) 100,000 IU improves symptoms after one month when compared to baseline (83791). The validity of this finding is limited by the lack of a control group.
Seborrheic keratosis. It is unclear if topical vitamin D analogues improve symptoms of seborrheic keratosis. Details: Preliminary clinical research suggests that topical ointments containing activated vitamin D in the form of tacalcitol, calcipotriol or maxacalcitol, applied for 3-12 months, can reduce tumor volume by at least 40% in 75% of patients with seborrheic keratosis. Additionally, over 30% of patients seem to experience complete tumor resolution or a reduction in tumor volume of at least 80% (84033). The validity of this finding is limited by the lack of a control group.
Sexual dysfunction. One small study suggests that injecting a large dose of vitamin D might improve sexual function. Details: A small clinical study in females with vitamin D deficiency and sexual dysfunction shows that receiving an intramuscular injection of vitamin D as cholecalciferol 300,000 IU once at baseline and a second time 4 weeks later improves sexual function at 4 and 8 weeks when compared with placebo (100896).
Sickle cell disease. One small study suggests that oral vitamin D reduces pain and improves quality of life in children with sickle cell disease with vitamin D insufficiency or deficiency. Details: A small clinical study in children with sickle cell disease shows that taking vitamin D3 (cholecalciferol) 40,000-100,000 IU weekly for 6 weeks reduces days with pain and improves physical activity and quality of life for up to 6 months when compared with placebo. Of the children included in the study, 82.5% had vitamin D insufficiency, while 52.5% were deficient in vitamin D (98918). It is unclear if vitamin D is effective for patients with sickle cell disease who have adequate levels of vitamin D.
Small for gestational age (SGA). It is unclear if oral vitamin D can reduce the risk for SGA births; the available evidence is conflicting. Details: Two meta-analyses of clinical research show no effect of vitamin D on the risk of SGA birth (84659,109055). However, one meta-analysis shows a 40% reduction in the risk of SGA births with vitamin D supplementation (95910). Also, one meta-analysis shows that when vitamin D supplementation is initiated before the 20^th week of gestation, the risk of SGA is reduced by 54% (109055). Most individual clinical trials are small and heterogeneous. Also, the formulation of vitamin D and/or vitamin D status at baseline may explain part of the discrepant findings. For example, a meta-analysis of observational research has found that a very low vitamin D status (serum level <12 ng/mL) during pregnancy is associated with increased odds of SGA births. This association does not seem to be present with less severe vitamin D deficiency (serum level <20 ng/mL) (105724). Clinical practice guidelines from the Endocrine Society conditionally recommend, with low certainty of evidence, empiric vitamin D supplementation from daily intake of fortified foods, vitamin D supplements, or prenatal vitamin formulations that contain vitamin D during pregnancy to potentially lower the risk of SGA births, as well as preeclampsia, intra-uterine mortality, preterm birth, and neonatal mortality. Empiric vitamin D supplementation is defined as supplementing with vitamin D above the Recommended Dietary Allowance without having tested serum vitamin D status (114502).
Statin-induced myalgia. It is unclear if oral vitamin D is beneficial for patients with statin-induced myalgia. Details: Observational research has found that taking oral vitamin D supplements is associated with decreased symptoms of myalgia in patients taking statin drugs. In a small case series, patients who discontinued statins due to myalgia were able to resume statin therapy after starting vitamin D supplements. The majority of patients with myalgia were found to be vitamin D deficient, with vitamin D levels less than 12 ng/mL at baseline (16829). An observational study has also found that administering 50,000 units of vitamin D2 (ergocalciferol) once a week for 12 weeks reversed symptoms of myalgia in 92% of statin treated patients with low serum vitamin D levels of less than 32 ng/mL (16831).
Stroke. Although low vitamin D levels are associated with higher risk of stroke, taking vitamin D supplements does not seem to reduce stroke risk. Details: Population research has found that low vitamin D levels are associated with an increased risk of stroke. Furthermore, increased dietary intake of vitamin D is associated with a reduced risk of stroke (15630,16618,93944,97303,106106). However, clinical research shows that vitamin D supplementation does not reduce stroke risk. Several meta-analyses and randomized controlled trials show that taking vitamin D alone or with calcium does not reduce the risk of stroke in patients with or without cardiovascular disease risk factors (16616,91343,97296,97308,106106,112022). It is difficult to draw firm conclusions from these studies, as they did not assess whether patients had adequate vitamin D levels at baseline. It is unclear if vitamin D supplementation might prevent strokes in patients with vitamin D deficiency.
Sunburn. Although there is interest in using oral vitamin D for the treatment of sunburns, there is insufficient reliable information about the clinical effects of vitamin D for this purpose.
Systemic lupus erythematosus (SLE). It is unclear if oral vitamin D is beneficial in patients with SLE. Details: While some observational research has found that adults with SLE are more likely to have vitamin D deficiency than healthy controls (102119), a small cross-sectional study in females has found no association between serum levels of 25-hydroxyvitamin D, SLE disease activity, and the presence or absence of lupus nephritis (107214). A meta-analysis of three small clinical studies shows that taking vitamin D3 (cholecalciferol) 2000 IU daily or 50,000 IU weekly seems to reduce anti-dsDNA positive, a marker of disease activity, when compared with placebo in patients with SLE (98190). However, the clinical significance of this finding is unclear. A small clinical trial in females with SLE shows that taking vitamin D3 5000 IU daily for 12 weeks modestly improves overall disease activity, but not quality of life, when compared with placebo (109735).
Thyroid cancer. It is unclear if oral vitamin D is beneficial in patients with thyroid cancer. Details: Observational research in patients undergoing thyroidectomy for differentiated thyroid cancer suggests that taking vitamin D daily for at least 6 months after surgery is associated with a 38% lower risk of all-cause mortality and a 33% lower risk of total cancer-related mortality when compared with no vitamin D supplementation at around 10 years' follow-up. However, vitamin D does not appear to be linked to a lower risk of thyroid cancer-related mortality in these patients (112018).
Ulcerative colitis. Limited evidence suggests that vitamin D may be beneficial in patients with ulcerative colitis. Details: A meta-analysis of mainly small clinical trials in patients treated with mesalazine shows that taking vitamin D for up to 24 weeks modestly increases clinical efficacy and reduces disease score when compared with mesalazine alone (109044). Also, a meta-analysis of small, low-quality clinical studies in patients with IBD, including Crohn disease and ulcerative colitis, shows that taking high- or low-dose vitamin D for up to 1 year reduces the rate of relapse when compared with control (98915). These findings are limited because of the heterogeneity of the included studies.
Upper respiratory tract infection (URTI). It is unclear if oral vitamin D is beneficial for dementia. Details: A large clinical trial shows that taking vitamin D 2800 IU daily, starting at gestational week 24 and continuing until one week after birth, reduces the risk of the child developing croup by 3 years of age by 40% when compared with olive oil as placebo. This risk reduction did not change after adjusting for the use of omega-3 fatty acids 2.4 grams daily, as well as for concomitant persistent wheeze and/or lower respiratory tract infections (109304).
Urinary incontinence. Limited evidence suggests that vitamin D may be beneficial in middle-aged, but not older, adults with urinary incontinence. Details: Clinical research in middle-aged premenopausal females with stress urinary incontinence and low vitamin D status shows that taking vitamin D 5000 IU once weekly for 12 weeks has a moderate to large beneficial effect on the severity of incontinence and quality of life when compared with placebo. Kegel exercises were performed by all participants (109736). However, vitamin D supplementation does not seem to be beneficial for reducing urinary incontinence in older adults. In older females and males, a large clinical trial shows that vitamin D3 (cholecalciferol) 2000 IU daily for 5 years does not reduce the incidence or progression of urinary incontinence when compared with placebo (109738,109741). In older males with low vitamin D status, vitamin D supplementation may actually increase some types of incontinence (109738).
Urinary tract infections (UTIs). It is unclear if oral vitamin D is beneficial for the prevention of UTIs in children. Details: A meta-analysis of 13 small observational studies in children suggests that lower levels of vitamin D are associated with 2.8-fold greater odds of UTI when compared with higher vitamin D levels. Further, this analysis shows that vitamin D deficiency in children is linked to 5.5-fold greater odds of UTI when compared with normal vitamin D levels (112030).
Urticaria. It is unclear if oral vitamin D is beneficial for the prevention or treatment of urticaria. Details: A meta-analysis of population research has found that having urticaria is associated with a slightly lower vitamin D blood level and a greater likelihood of vitamin D deficiency when compared with individuals without urticaria. In addition, a meta-analysis of 6 clinical trials shows that taking high-dose vitamin D at an average daily dose of at least 4100 IU has a modest effect on the severity of urticaria symptoms (106115).
Uterine fibroids. Some evidence suggests that the risk of developing uterine fibroids is linked to vitamin D status, and that fibroid size is reduced by vitamin D supplements. However, it is unclear if oral vitamin D is beneficial for preventing the recurrence of uterine fibroids. Details: Observational research suggests that uterine fibroids are linked to vitamin D deficiency, with normal vitamin D levels associated with 32% lower odds of developing uterine fibroids. A meta-analysis of 5 clinical trials shows that taking vitamin D for at least 8 weeks reduces uterine fibroid size when compared with placebo. One clinical study shows that the recurrence rate for uterine fibroids is about 9% with vitamin D supplementation, compared with 18% without. However, a clinical study in patients with low vitamin D levels undergoing hysteroscopic myomectomy for uterine fibroids shows that taking vitamin D 1000 IU daily for 12 months does not improve the rate of recurrence when compared with placebo (108422).
Vaginal atrophy. It is unclear if oral vitamin D is beneficial for vaginal atrophy. There is limited evidence on the topical use of vitamin D in vaginal atrophy in postmenopausal adults or patients taking tamoxifen. Details: A small cross-sectional study in postmenopausal adults has found that taking a vitamin D supplement for at least one year improves the maturation index of superficial vaginal wall cells when compared with those who do not take vitamin D. However, symptoms of vaginal atrophy were not different between groups (16879). Vitamin D has also been evaluated for vaginal atrophy due to tamoxifen. A small clinical trial in females with breast cancer using tamoxifen shows that receiving vitamin D 1000 IU vaginal suppositories daily for 8 weeks improves maturation index of vaginal walls and self-reported symptoms when compared with placebo (99773).
Vertigo. It is unclear if oral vitamin D is beneficial in patients with vertigo. Details: An analysis of observational research suggests that lower serum levels of vitamin D are associated with a higher risk of benign paroxysmal positional vertigo (BPPV) when compared with higher vitamin D levels (114579). However, it is unclear if vitamin D supplementation can reduce the risk of BPPV in individuals with low vitamin D levels. Vitamin D has been evaluated in combination with other ingredients for the treatment of BPPV. A large clinical study in adults with recurrent BPPV shows that taking vitamin D 400 IU and calcium 500 mg twice daily for one year reduces the risk of recurrence by 27% when compared with no treatment. The number needed to treat to prevent vertigo was 4 (103681). It is unclear if this benefit is due to vitamin D, calcium, or the combination.
Vitiligo. Although there is interest in using oral vitamin D for vitiligo, there is insufficient reliable information about the clinical effects of vitamin D for this condition.
Warts. Although there is interest in using topical vitamin D derivatives for warts, there is insufficient reliable information about the clinical effects of vitamin D for this condition. More evidence is needed to rate vitamin D for these uses.

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Safety view details

Below is general information about the safety of the known ingredients contained in the product Fermented Vitamin D3 2000 IU. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.

REISHI MUSHROOM (organic Reishi)

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

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TURMERIC

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.

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VITAMIN D (Vitamin D3)

LIKELY SAFE ...when used orally or intramuscularly and appropriately. Vitamin D has been safely used in a wide range of doses (7555,16888,16891,17476,95913,98186,104619,105209,109059). When used orally long-term, doses should not exceed the tolerable upper intake level (UL) of 4000 IU (100 mcg) daily for adults (17506,99773); however, much higher doses such as 50,000 IU (1250 mcg) weekly orally for 6-12 weeks are often needed for the short-term treatment of vitamin D deficiency (16891,17476). Monthly oral doses of up to 60,000 IU (1500 mcg) have also been safely used for up to 5 years (105726). Toxicity usually does not occur until plasma levels exceed 150 ng/mL (17476).

POSSIBLY UNSAFE ...when used orally in excessive doses, long-term. Taking doses greater than the tolerable upper intake level (UL) of 4000 IU (100 mcg) daily for adults for long periods can increase the risk of hypercalcemia (17506); however, much higher doses are often needed for short-term treatment of vitamin D deficiency. Toxicity typically occurs when levels exceed 150 ng/mL (17476).

CHILDREN: LIKELY SAFE
when used orally and appropriately. When used long-term, doses should not exceed the tolerable upper intake level (UL) of 1000 IU (25 mcg) daily for those 0-6 months of age, 1500 IU (37.5 mcg) daily for those 6-12 months of age, 2500 IU (62.5 mcg) daily for those 1-3 years of age, 3000 IU (75 mcg) daily for those 4-8 years of age, and 4000 IU (100 mcg) daily for those 9 years and older (17506); however, much higher doses are often needed for the short-term treatment of vitamin D deficiency. Some research shows that giving vitamin D 14,000 IU (350 mcg) weekly for a year in children aged 10-17 years is safe (16875). A meta-analysis of clinical studies shows that 1000 IU (25 mcg) daily in those up to a year of age and greater than 2000 IU (50 mcg) daily in those aged 1-6 years does not increase the risk of serious adverse events (108424).

CHILDREN: POSSIBLY UNSAFE
when used orally in excessive doses for longer than one year. Taking doses greater than the tolerable upper intake level (UL) long-term can increase the risk of hypercalcemia (17506).

PREGNANCY: LIKELY SAFE
when used orally and appropriately. Vitamin D is safe when used in doses below the tolerable upper intake level (UL) of 4000 IU (100 mcg) daily (17506,95910).

PREGNANCY: POSSIBLY UNSAFE
when used orally in excessive amounts. Tell patients not to use doses above the tolerable upper intake level (UL) of 4000 IU (100 mcg) daily. Hypercalcemia during pregnancy due to excessive vitamin D intake can lead to several fetal adverse effects, including suppression of parathyroid hormone, hypocalcemia, tetany, seizures, aortic valve stenosis, retinopathy, and mental and/or physical developmental delay (17506).

LACTATION: LIKELY SAFE
when used orally and appropriately. Vitamin D is safe when used in doses below the tolerable upper intake level (UL) of 4000 IU (100 mcg) daily (17506).

LACTATION: POSSIBLY UNSAFE
when used orally in excessive amounts. Tell patients not to use doses above the tolerable upper intake level (UL) of 4000 IU (100 mcg) daily (17506).

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Interactions with Drugs view details

Below is general information about the interactions of the known ingredients contained in the product Fermented Vitamin D3 2000 IU. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.

REISHI MUSHROOM (organic Reishi)

ANTICOAGULANT/ANTIPLATELET DRUGS

Interaction Rating = Moderate Be cautious with this combination.

Severity = High • Occurrence = Possible • Level of Evidence = D

Theoretically, high doses of reishi mushroom might increase the risk of bleeding.

Details

A dose of 1.5 grams daily of reishi mushroom does not seem to decrease platelet aggregation, but a higher dose of 3 grams daily does (5476,13235).

ANTIDIABETES DRUGS

Interaction Rating = Moderate Be cautious with this combination.

Severity = Moderate • Occurrence = Possible • Level of Evidence = D

Theoretically, reishi mushroom might have additive effects with antidiabetes drugs.

Details

Animal research suggests that reishi mushroom decreases blood sugar (70769). However, in patients with type 2 diabetes, taking reishi mushroom does not reduce fasting glucose levels, and its effects on glycated hemoglobin are inconsistent (70801,91435).

ANTIHYPERTENSIVE DRUGS

Interaction Rating = Moderate Be cautious with this combination.

Severity = Moderate • Occurrence = Possible • Level of Evidence = D

Theoretically, concurrent use of reishi mushroom with antihypertensive drugs might increase the risk of hypotension.

Details

Reishi mushroom has shown hypotensive activity in animal research (5488,70784). Clinical evidence suggests that reishi mushroom reduces blood pressure in some, but not all, patients with hypertension (70786,70802).

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TURMERIC

ALKYLATING AGENTS

Interaction Rating = Moderate Be cautious with this combination.

Severity = High • Occurrence = Possible • Level of Evidence = D

Turmeric has antioxidant effects. Theoretically, this may reduce the activity of chemotherapy drugs that generate free radicals. However, research is conflicting.

Details

In vitro research suggests that curcumin, a constituent of turmeric, inhibits mechlorethamine-induced apoptosis of breast cancer cells by up to 70%. Also, animal research shows that curcumin inhibits cyclophosphamide-induced tumor regression (96126). However, some in vitro research shows that curcumin does not affect the apoptosis capacity of etoposide. Also, other laboratory research suggests that curcumin might augment the cytotoxic effects of alkylating agents. Reasons for the discrepancies may relate to the dose of curcumin and the specific chemotherapeutic agent. Lower doses of curcumin might have antioxidant effects while higher doses might have pro-oxidant effects (96125). More evidence is needed to determine what effect, if any, turmeric might have on alkylating agents.

AMLODIPINE (Norvasc)

Interaction Rating = Moderate Be cautious with this combination.

Severity = Moderate • Occurrence = Possible • Level of Evidence = D

Taking turmeric with amlodipine may increase levels of amlodipine.

Details

Animal research shows that giving amlodipine 1 mg/kg as a single dose following the use of turmeric extract 200 mg/kg daily for 2 weeks increases the maximum concentration and area under the curve by 53% and 56%, respectively, when compared with amlodipine alone (107113). Additional animal research shows that taking amlodipine 1 mg/kg with a curcumin 2 mg/kg pretreatment for 10 days increases the maximum concentration and area under the curve by about 2-fold when compared with amlodipine alone (103099).

ANTICOAGULANT/ANTIPLATELET DRUGS

Interaction Rating = Moderate Be cautious with this combination.

Severity = High • Occurrence = Possible • Level of Evidence = B

Turmeric may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs. However, research is conflicting.

Details

Curcumin, a constituent of turmeric, has demonstrated antiplatelet effects in vitro (11143,81204,81271). Furthermore, two case reports have found that taking turmeric along with warfarin or fluindione was associated with an increased international normalized ratio (INR) (89718,100906). However, one clinical study in healthy volunteers shows that taking curcumin 500 mg daily for 3 weeks, alone or with aspirin 100 mg, does not increase antiplatelet effects or bleeding risk (96137). It is possible that the dose of turmeric used in this study was too low to produce a notable effect.

ANTIDIABETES DRUGS

Interaction Rating = Moderate Be cautious with this combination.

Severity = Moderate • Occurrence = Possible • Level of Evidence = B

Theoretically, taking turmeric with antidiabetes drugs might increase the risk of hypoglycemia.

Details

Animal research and case reports suggest that curcumin, a turmeric constituent, can reduce blood glucose levels in patients with diabetes (79692,79984,80155,80313,80315,80476,80553,81048,81219). Furthermore, clinical research in adults with type 2 diabetes shows that taking curcumin 475 mg daily for 10 days prior to taking glyburide 5 mg decreased postprandial glucose levels for up to 24 hours when compared with glyburide alone, despite the lack of a significant pharmacokinetic interaction (96133). Another clinical study in patients with diabetes on hemodialysis shows that taking curcumin 80 mg daily for 12 weeks can reduce blood glucose levels when compared with placebo (104149).

ANTITUMOR ANTIBIOTICS

Interaction Rating = Moderate Be cautious with this combination.

Severity = High • Occurrence = Possible • Level of Evidence = D

Turmeric has antioxidant effects. Theoretically, this may reduce the activity of chemotherapy drugs that generate free radicals. However, research is conflicting.

Details

In vitro and animal research shows that curcumin, a constituent of turmeric, inhibits doxorubicin-induced apoptosis of breast cancer cells by up to 65% (96126). However, curcumin does not seem to affect the apoptosis capacity of daunorubicin. In fact, some research shows that curcumin might augment the cytotoxic effects of antitumor antibiotics, increasing their effectiveness. Reasons for the discrepancies may relate to the dose of curcumin and the chemotherapeutic agent. Lower doses of curcumin might have antioxidant effects while higher doses might have pro-oxidant effects (96125). More evidence is needed to determine what effects, if any, antioxidants such as turmeric have on antitumor antibiotics.

CYTOCHROME P450 1A1 (CYP1A1) SUBSTRATES

Interaction Rating = Minor Be watchful with this combination.

Severity = Mild • Occurrence = Possible • Level of Evidence = D

Theoretically, turmeric might increase or decrease levels of drugs metabolized by CYP1A1. However, research is conflicting.

Details

Most in vitro and animal research suggests that the turmeric constituent, curcumin, INHIBITS CYP1A1, primarily in the liver (15823,21495,80876,81411). However, some evidence from in vitro research suggests that curcumin may INDUCE CYP1A1 in the intestines (21500).

CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES

Interaction Rating = Minor Be watchful with this combination.

Severity = Mild • Occurrence = Possible • Level of Evidence = D

Theoretically, turmeric might increase levels of drugs metabolized by CYP1A2. However, research is conflicting.

Details

In vitro and animal research show that the turmeric constituent, curcumin, inhibits CYP1A2 (15823,21497,81304). However, other in vitro research suggests that curcumin does not significantly affect CYP1A2 (22000).

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

Interaction Rating = Moderate Be cautious with this combination.

Severity = High • Occurrence = Possible • Level of Evidence = D

Turmeric might increase levels of drugs metabolized by CYP3A4.

Details

In vitro and animal research show that turmeric and its constituents curcumin and curcuminoids inhibit CYP3A4 (21497,21498,21499). Also, 8 case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking turmeric and cancer medications that are CYP3A4 substrates, including everolimus, ruxolitinib, ibrutinib, and palbociclib, and bortezomib (111644). In another case report, a transplant patient presented with acute nephrotoxicity and elevated tacrolimus levels after consuming turmeric powder at a dose of 15 or more spoonfuls daily for ten days prior. It was thought that turmeric increased levels of tacrolimus due to CYP3A4 inhibition (93544).
Conversely, other in vitro research suggests that turmeric induces CYP3A4 activity, leading to reduced levels of CYP3A4 substrates (111404). However, this interaction has not been reported in humans.

DOCETAXEL (Taxotere)

Interaction Rating = Minor Be watchful with this combination.

Severity = Mild • Occurrence = Possible • Level of Evidence = D

Theoretically, turmeric might increase blood levels of oral docetaxel.

Details

Animal research suggests that the turmeric constituent, curcumin, enhances the oral bioavailability of docetaxel (80999). However, the significance of this interaction is unclear, as this drug is typically administered intravenously in clinical settings.

ESTROGENS

Interaction Rating = Minor Be watchful with this combination.

Severity = Mild • Occurrence = Possible • Level of Evidence = D

Theoretically, large amounts of turmeric might interfere with hormone replacement therapy through competition for estrogen receptors.

Details

In vitro research shows that curcumin, a constituent of turmeric, displaces the binding of estrogen to its receptors (21486).

GLYBURIDE (Diabeta, others)

Interaction Rating = Minor Be watchful with this combination.

Severity = Mild • Occurrence = Possible • Level of Evidence = B

Theoretically, taking turmeric and glyburide in combination might increase the risk of hypoglycemia.

Details

Clinical research shows that taking curcumin 475 mg daily for 10 days prior to taking glyburide 5 mg increases blood levels of glyburide by 12% at 2 hours after the dose in patients with type 2 diabetes. While maximal blood concentrations of glyburide were not affected, turmeric modestly decreased postprandial glucose levels for up to 24 hours when compared to glyburide alone, possibly due to the hypoglycemic effect of turmeric demonstrated in animal research (96133).

HEPATOTOXIC DRUGS

Interaction Rating = Moderate Be cautious with this combination.

Severity = High • Occurrence = Possible • Level of Evidence = D

Theoretically, turmeric might increase the risk of liver damage when taken with hepatotoxic drugs.

Details

There is concern that turmeric might cause hepatotoxicity, especially when highly bioavailable formulations are used in high doses (103633,107122,109288,110221).

LOSARTAN (Cozaar)

Interaction Rating = Minor Be watchful with this combination.

Severity = Mild • Occurrence = Possible • Level of Evidence = D

Theoretically, turmeric might increase the effects of losartan.

Details

Research in hypertensive rats shows that taking turmeric can increase the hypotensive effects of losartan (110897).

METHOTREXATE (Trexall, others)

Interaction Rating = Moderate Be cautious with this combination.

Severity = High • Occurrence = Possible • Level of Evidence = D

Theoretically, turmeric might have additive effects when used with hepatotoxic drugs such as methotrexate.

Details

In one case report, a 39-year-old female taking methotrexate, turmeric, and linseed oil developed hepatotoxicity (111644).

NORFLOXACIN (Noroxin)

Interaction Rating = Minor Be watchful with this combination.

Severity = Mild • Occurrence = Possible • Level of Evidence = D

Theoretically, turmeric might increase the effects and adverse effects of norfloxacin.

Details

Animal research shows that taking curcumin, a turmeric constituent, can increase blood levels of orally administered norfloxacin (80863).

ORGANIC ANION-TRANSPORTING POLYPEPTIDE SUBSTRATES (OATP)

Interaction Rating = Moderate Be cautious with this combination.

Severity = Moderate • Occurrence = Possible • Level of Evidence = D

Theoretically, turmeric might increase blood levels of OATP4C1 substrates.

Details

In vitro research shows that the turmeric constituent curcumin competitively inhibits OATP4C1 transport. This transporter is expressed in the kidney and facilitates the renal excretion of certain drugs (113337). Theoretically, taking turmeric might decrease renal excretion of OATP substrates.

P-GLYCOPROTEIN SUBSTRATES

Interaction Rating = Minor Be watchful with this combination.

Severity = Mild • Occurrence = Possible • Level of Evidence = D

Theoretically, turmeric might increase the absorption of P-glycoprotein substrates.

Details

In vitro and animal research shows that curcuminoids and other constituents found in turmeric can inhibit P-glycoprotein expression and activity (21472,21473,21474,21475,21476,21477,21478,21479,21480)(21482,21484,111644).

PACLITAXEL (Abraxane, Onxol)

Interaction Rating = Minor Be watchful with this combination.

Severity = Mild • Occurrence = Possible • Level of Evidence = D

Theoretically, turmeric might alter blood levels of paclitaxel, although any effect may not be clinically relevant.

Details

Clinical research in adults with breast cancer receiving intravenous paclitaxel suggests that taking turmeric may modestly alter paclitaxel pharmacokinetics. Patients received paclitaxel on day 1, followed by either no treatment or turmeric 2 grams daily from days 2-22. Pharmacokinetic modeling suggests that turmeric reduces the maximum concentration and area under the curve of paclitaxel by 12.1% and 7.7%, respectively. However, these changes are not likely to be considered clinically relevant (108876). Conversely, animal research suggests that curcumin, a constituent of turmeric, enhances the oral bioavailability of paclitaxel (22005). However, the significance of this interaction is unclear, as this drug is typically administered intravenously in clinical settings.

SULFASALAZINE (Azulfidine)

Interaction Rating = Moderate Be cautious with this combination.

Severity = Moderate • Occurrence = Probable • Level of Evidence = B

Turmeric might increase the effects and adverse effects of sulfasalazine.

Details

Clinical research shows that taking the turmeric constituent, curcumin, can increase blood levels of sulfasalazine by 3.2-fold (81131).

TACROLIMUS (Prograf)

Interaction Rating = Moderate Be cautious with this combination.

Severity = High • Occurrence = Possible • Level of Evidence = D

Turmeric might increase the effects and adverse effects of tacrolimus.

Details

In one case report, a transplant patient presented with acute nephrotoxicity and elevated tacrolimus levels of 29 ng/mL. The patient previously had tacrolimus levels within the therapeutic range at 9.7 ng/mL. Ten days prior to presenting at the emergency room the patient started consumption of turmeric powder at a dose of 15 or more spoonfuls daily. It was thought that turmeric increased levels of tacrolimus due to cytochrome P450 3A4 (CYP3A4) inhibition (93544). In vitro and animal research show that turmeric and its constituent curcumin inhibit CYP3A4 (21497,21498,21499).

TALINOLOL

Interaction Rating = Moderate Be cautious with this combination.

Severity = Mild • Occurrence = Probable • Level of Evidence = B

Turmeric may reduce the absorption of talinolol in some situations.

Details

Clinical research shows that taking curcumin for 6 days decreases the bioavailability of talinolol when taken together on the seventh day (80079). The clinical significance of this effect is unclear.

TAMOXIFEN (Nolvadex)

Interaction Rating = Moderate Be cautious with this combination.

Severity = High • Occurrence = Possible • Level of Evidence = B

Theoretically, turmeric might reduce the levels and clinical effects of tamoxifen.

Details

In a small clinical trial in patients with breast cancer taking tamoxifen 20-30 mg daily, adding curcumin 1200 mg plus piperine 10 mg three times daily reduces the 24-hour area under the curve of tamoxifen and the active metabolite endoxifen by 12.8% and 12.4%, respectively, as well as the maximum concentrations of tamoxifen, when compared with tamoxifen alone. However, in the absence of piperine, the area under the curve for endoxifen and the maximum concentration of tamoxifen were not significantly reduced. Effects were most pronounced in patients who were extensive cytochrome P450 (CYP) 2D6 metabolizers (107123).

TOPOISOMERASE I INHIBITORS

Interaction Rating = Moderate Be cautious with this combination.

Severity = High • Occurrence = Possible • Level of Evidence = D

Turmeric has antioxidant effects. There is some concern that this may reduce the activity of chemotherapy drugs that generate free radicals. However, research is conflicting.

Details

In vitro research shows that curcumin, a constituent of turmeric, inhibits camptothecin-induced apoptosis of breast cancer cells by up to 71% (96126). However, other in vitro research shows that curcumin augments the cytotoxic effects of camptothecin. Reasons for the discrepancies may relate to the dose of curcumin and the chemotherapeutic agents. Lower doses of curcumin might have antioxidant effects while higher doses might have pro-oxidant effects (96125). More evidence is needed to determine what effect, if any, turmeric might have.

WARFARIN (Coumadin)

Interaction Rating = Moderate Be cautious with this combination.

Severity = High • Occurrence = Possible • Level of Evidence = D

Turmeric might increase the risk of bleeding with warfarin.

Details

One case of increased international normalized ratio (INR) has been reported for a patient taking warfarin who began taking turmeric. Prior to taking turmeric, the patient had stable INR measurements. Within a few weeks of starting turmeric supplementation, the patient's INR increased to 10 (100906). Additionally, curcumin, the active constituent in turmeric, has demonstrated antiplatelet effects in vitro (11143,81204,81271), which may produce additive effects when taken with warfarin.

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VITAMIN D (Vitamin D3)

ALUMINUM

Interaction Rating = Moderate Be cautious with this combination.

Severity = Mild • Occurrence = Probable • Level of Evidence = B

Vitamin D might increase aluminum absorption and toxicity, but this has only been reported in people with renal failure.

Details

The protein that transports calcium across the intestinal wall can also bind and transport aluminum. This protein is stimulated by vitamin D, which may therefore increase aluminum absorption (11595,11597,22916). This mechanism may contribute to increased aluminum levels and toxicity in people with renal failure, when they take vitamin D and aluminum-containing phosphate binders chronically (11529,11596,11597).

ATORVASTATIN (Lipitor)

Interaction Rating = Moderate Be cautious with this combination.

Severity = Mild • Occurrence = Probable • Level of Evidence = B

Vitamin D might reduce absorption of atorvastatin.

Details

A small, low-quality clinical study shows that taking vitamin D reduces levels of atorvastatin and its active metabolites by up to 55%. However, while atorvastatin levels decreased, total cholesterol, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein (HDL) cholesterol levels did not substantially change (16828). Atorvastatin is metabolized in the gut by CYP3A4 enzymes, and researchers theorized that vitamin D might induce CYP3A4, causing reduced levels of atorvastatin. However, this proposed mechanism was not specifically studied.

CALCIPOTRIENE (Dovonex)

Interaction Rating = Moderate Be cautious with this combination.

Severity = Moderate • Occurrence = Probable • Level of Evidence = D

Taking calcipotriene with vitamin D increases the risk for hypercalcemia.

Details

Calcipotriene is a vitamin D analog used topically for psoriasis. It can be absorbed in sufficient amounts to cause systemic effects, including hypercalcemia (15). Theoretically, combining calcipotriene with vitamin D supplements might increase the risk of hypercalcemia.

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

Interaction Rating = Minor Be watchful with this combination.

Severity = Mild • Occurrence = Possible • Level of Evidence = D

Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.

Details

There is some concern that vitamin D might induce CYP3A4. In vitro research suggests that vitamin D induces CYP3A4 transcription. Additionally, observational research has found that increased UV light exposure and serum vitamin D levels are associated with decreased serum levels of CYP3A4 substrates such as tacrolimus and sirolimus, while no association between UV light exposure or vitamin D levels and levels of mycophenolic acid, a non-CYP3A4 substrate, was found (110539). A small, low-quality clinical study shows that taking vitamin D reduces levels of the CYP3A4 substrate atorvastatin and its active metabolites by up to 55%; however, the clinical effects of atorvastatin were not reduced (16828). While researchers theorized that vitamin D might induce CYP3A4, this proposed mechanism was not specifically studied.

DIGOXIN (Lanoxin)

Interaction Rating = Moderate Be cautious with this combination.

Severity = High • Occurrence = Possible • Level of Evidence = D

Theoretically, hypercalcemia induced by high-dose vitamin D can increase the risk of arrhythmia from digoxin.

Details

High doses of vitamin D can cause hypercalcemia. Hypercalcemia increases the risk of fatal cardiac arrhythmias with digoxin (15). Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and digoxin concurrently.

DILTIAZEM (Cardizem, others)

Interaction Rating = Moderate Be cautious with this combination.

Severity = Moderate • Occurrence = Probable • Level of Evidence = B

Theoretically, hypercalcemia induced by high-dose vitamin D can reduce the therapeutic effects of diltiazem for arrhythmia.

Details

High doses of vitamin D can cause hypercalcemia. Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation (10574). Theoretically this could also occur with diltiazem. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and diltiazem concurrently.

THIAZIDE DIURETICS

Interaction Rating = Moderate Be cautious with this combination.

Severity = Moderate • Occurrence = Probable • Level of Evidence = D

Theoretically, taking thiazide diuretics and high-dose vitamin D can increase the risk of hypercalcemia.

Details

Thiazide diuretics decrease urinary calcium excretion, which could lead to hypercalcemia if vitamin D supplements are taken concurrently (3072,11541,69580). This has been reported in people being treated with vitamin D for hypoparathyroidism, and also in elderly people with normal parathyroid function who were taking a thiazide, vitamin D, and calcium-containing antacids daily (11539,11540).

VERAPAMIL (Calan, others)

Interaction Rating = Moderate Be cautious with this combination.

Severity = Moderate • Occurrence = Probable • Level of Evidence = B

Hypercalcemia induced by high-dose vitamin D can reduce the therapeutic effects of verapamil for arrhythmia.

Details

Hypercalcemia due to high doses of vitamin D can reduce the effectiveness of verapamil in atrial fibrillation (10574). Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and verapamil concurrently.

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Adverse Effects view details

Report an Adverse Reaction to Fermented Vitamin D3 2000 IU

Below is general information about the adverse effects of the known ingredients contained in the product Fermented Vitamin D3 2000 IU. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.

REISHI MUSHROOM (organic Reishi)

General ...Orally, reishi mushroom is generally well tolerated.
Most Common Adverse Effects:
Orally: Dizziness, dry mouth, itching, nausea, rash, and stomach upset.

Dermatologic ...Orally, reishi mushroom can cause itching, rash, and other skin reactions (12,5479).

Gastrointestinal ...Orally, reishi mushroom can cause dryness of the mouth, throat, or nasal cavity, nausea, stomach upset, and, more rarely, diarrhea (12,70779,91438,108309).

Hematologic ...Orally, reishi mushroom can cause nosebleed and bloody stools (12,91438).

Hepatic ...One case of hepatotoxicity and one case of fatal fulminant hepatitis have been reported in patients who had used reishi mushroom powder for 1-2 months (70766). There is a case report of a 61-year-old male with hypereosinophilia associated with hepatic nodules following the use of reishi mushroom powder for about 2 months. Symptoms resolved after discontinuation of the product. Although these side effects were thought to be associated with the use of reishi mushroom powder, it is unclear if other factors played a role. The patient had been taking tegafur, gimeracil, and oteracil potassium for about 4 months following anterior resection for rectal adenocarcinoma but discontinued these agents and initiated reishi mushroom due to liver injury (108312).

Neurologic/CNS ...Orally, reishi mushroom can cause dizziness (91438). Other rare symptoms include insomnia and headache (70776,70779).

Pulmonary/Respiratory ...Respiratory allergy to reishi spores can occur (12,5479). Sore throat and runny nose have also been reported (70776,91438).

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TURMERIC

General ...Orally and topically, turmeric is generally well tolerated.
Most Common Adverse Effects:
Orally: Constipation, dyspepsia, diarrhea, distension, gastroesophageal reflux, nausea, and vomiting.
Topically: Curcumin, a constituent of turmeric, can cause contact urticaria and pruritus.

Cardiovascular ...Orally, a higher dose of turmeric in combination with other ingredients has been linked to atrioventricular heart block in one case report. It is unclear if turmeric caused this adverse event or if other ingredients or a contaminant were the cause. The patient had taken a combination supplement containing turmeric 1500-2250 mg, black soybean 600-900 mg, mulberry leaves, garlic, and arrowroot each about 300-450 mg, twice daily for one month before experiencing atrioventricular heart block. Heart rhythm normalized three days after discontinuation of the product. Re-administration of the product resulted in the same adverse effect (17720).

Dermatologic ...Following occupational and/or topical exposure, turmeric or its constituents curcumin, tetrahydrocurcumin, or turmeric oil, can cause allergic contact dermatitis (11146,79270,79470,79934,81410,81195). Topically, curcumin can also cause rash or contact urticaria (79985,97432,112117). In one case, a 60-year-old female, with no prior reactivity to regular oral consumption of turmeric products, developed urticaria after topical application of turmeric massage oil (97432). A case of pruritus has been reported following topical application of curcumin ointment to the scalp for the treatment of melanoma (11148). Yellow discoloration of the skin has been reported rarely in clinical research (113356). Orally, curcumin may cause pruritus, but this appears to be relatively uncommon (81163,97427,104148). Pitting edema may also occur following oral intake of turmeric extract, but the frequency of this adverse event is less common with turmeric than with ibuprofen (89720). A combination of curcumin plus fluoxetine may cause photosensitivity (89728).

Gastrointestinal ...Orally, turmeric can cause gastrointestinal adverse effects (107110,107112,112118), including constipation (81149,81163,96135,113355), flatulence and yellow, hard stools (81106,96135), nausea and vomiting (10453,17952,89720,89728,96127,96131,96135,97430,112117,112118), diarrhea or loose stool (10453,17952,18204,89720,96135,110223,112117,112118), dyspepsia (17952,89720,89721,96161,112118), gastritis (89728), distension and gastroesophageal reflux disease (18204,89720), abdominal fullness and pain (81036,89720,96161,97430), epigastric burning (81444), and tongue staining (89723).

Hepatic ...Orally, turmeric has been associated with liver damage, including non-infectious hepatitis, cholestasis, and hepatocellular liver injury. There have been at least 70 reports of liver damage associated with taking turmeric supplements for at least 2 weeks and for up to 14 months. Most cases of liver damage resolved upon discontinuation of the turmeric supplement. Sometimes, turmeric was used concomitantly with other supplements and medications (99304,102346,103094,103631,103633,103634,107122,109288,110221). The Drug-Induced Liver Injury Network (DILIN) has identified 10 cases of liver injury which were considered to be either definitely, highly likely, or probably associated with turmeric; none of these cases were associated with the use of turmeric in combination with other potentially hepatotoxic supplements. Most patients (90%) presented with hepatocellular pattern of liver injury. The median age of these case reports was 56 years and 90% identified as White. In these case reports, the carrier frequency on HLAB*35:01 was 70%, which is higher than the carrier frequency found in the general population. Of the ten patients, 5 were hospitalized and 1 died from liver injury (109288).
It is not clear if concomitant use with other supplements or medications contributes to the risk for liver damage. Many case reports did not report turmeric formulation, dosing, or duration of use (99304,103094,103631,103634,109288). However, at least 10 cases involved high doses of curcumin (250-1812.5 mg daily) and the use of highly bioavailable formulations such as phytosomal curcumin and formulations containing piperine (102346,103633,107122,109288,110221).

Neurologic/CNS ...Orally, the turmeric constituent curcumin can cause vertigo, but this effect seems to be uncommon (81163).

Psychiatric ...Orally, the turmeric constituent curcumin or a combination of curcumin and fluoxetine can cause giddiness, although this event seems to be uncommon (81206,89728).

Renal ...Orally, turmeric has been linked to one report of kidney failure, although the role of turmeric in this case is unclear. A 69-year-old male developed kidney failure related to calcium oxalate deposits in the renal tubules following supplementation with turmeric 2 grams daily for 2 years as an anti-inflammatory for pelvic pain. While turmeric is a source of dietary oxalates, pre-existing health conditions and/or chronic use of antibiotics may have contributed to the course of disease (113343).

Other ...There is a single case report of death associated with intravenous use of turmeric. However, analysis of the treatment vial suggests that the vial contained only 0.023% of the amount of curcumin listed on the label. Also, the vial had been diluted in a solution of ungraded polyethylene glycol (PEG) 40 castor oil that was contaminated with 1.25% diethylene glycol. Therefore the cause of death is unknown but is unlikely to be related to the turmeric (96136).

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VITAMIN D (Vitamin D3)

General ...Orally or intramuscularly, vitamin D is well tolerated.
Serious Adverse Effects (Rare):
Orally or intramuscularly: Excessive doses can lead to vitamin D toxicity with symptoms of hypercalcemia, and also sometimes azotemia and anemia.

Cardiovascular ...Vitamin D intoxication can occur when vitamin D supplements are taken orally in excessive doses. Rarely, people develop hypertension (10142). An analysis of clinical research suggests that, when taken orally, vitamin D might modestly increase levels of low-density lipoprotein (LDL)-cholesterol. However, it is not clear if this increase is clinically significant (84642).

Gastrointestinal ...Orally, vitamin D may cause dry mouth. In clinical research, intake of vitamin D 50,000 IU weekly for 4 weeks followed by 50,000 IU monthly for 5 months thereafter was associated with a 3.7-fold increase in reports of dry mouth compared with placebo (91348).Vitamin D intoxication can occur when vitamin D supplements are taken orally in excessive doses. Symptoms of vitamin D toxicity include pancreatitis (10142,84433). Vomiting occurred in one patient given a single dose of 200,000 IU (104624).

Genitourinary ...Vitamin D intoxication can occur when vitamin D supplements are taken orally in excessive doses. Advanced symptoms may include decreased libido (10142). Vaginal discharge and itching have been reported in a clinical trial following oral use (91348).

Hematologic ...Lab values of urinary and blood calcium, phosphate, albumin, blood urea nitrogen, serum cholesterol, aspartate aminotransferase, and alanine aminotransferase concentrations might increase with vitamin D use, especially with high doses (10142,91349,93943).
A case of elevated international normalized ration (INR) has been reported for an 84 year-old patient who took vitamin D 50,000 IU daily for 2 months. The patient's serum levels of vitamin D increased from <7 ng/mL to 100 ng/mL over 6 months. To resolve symptoms, vitamin D supplementation was discontinued (84433).

Musculoskeletal ...Vitamin D intoxication can occur when vitamin D supplements are taken in excessive doses (10142,17506). Symptoms of vitamin D toxicity include osteoporosis in adults and decreased growth in children (10142).

Ocular/Otic ...Vitamin D intoxication can occur when vitamin D supplements are taken orally in excessive doses (10142,17506). Symptoms of vitamin D toxicity include calcific conjunctivitis and photophobia (10142).

Psychiatric ...Vitamin D intoxication can occur when vitamin D supplements are taken orally in excessive doses (10142,17506). In rare cases, symptoms of vitamin D toxicity include psychosis (10142,93002).

Pulmonary/Respiratory ...Vitamin D intoxication can occur when vitamin D supplements are taken orally in excessive doses. Advanced symptoms of vitamin D toxicity may include runny nose (10142,17506,93002).

Renal ...Vitamin D intoxication can occur when vitamin D supplements are taken orally in excessive doses. Symptoms of vitamin D toxicity include azotemia. Vitamin D may also cause hypercalcemia, with advanced symptoms including kidney stones or kidney insufficiency due to precipitation of calcium phosphate in the tubules. Symptoms of renal impairment include frequency, nighttime awakening to urinate, thirst, inability to concentrate urine, and proteinuria. Renal impairment is usually reversible with discontinuation of vitamin D supplements (10142,93002,93943,110831,110833).

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Report an Adverse Reaction to Fermented Vitamin D3 2000 IU

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