Friendly Fiber by NSI - Nutraceutical Sciences Institute

LIKELY EFFECTIVE

• Coronary heart disease (CHD). A diet high in soluble fiber, such as that found in oats, reduces the risk of CHD. Details: Clinical research shows that a diet containing foods high in fiber, such as oats, oat bran, or whole oat flour, reduces the risk of CHD (2737,4960,4962,4963,4964,4965,4966,4967,4968). In 1993, the US Food and Drug Administration (FDA) approved a health claim stating that consuming at least 3 grams of soluble fiber per day, as part of a diet low in saturated fat and cholesterol, may reduce the risk of CHD (102336). However, clinical studies show that at least 3.6 grams of soluble fiber daily is needed to reduce the risk of CHD (5786,5787,5788,5794,5795,5796).
• Dyslipidemia. A diet rich in soluble fiber, such as that found in oats, can reduce cholesterol by a moderate amount. Details: Oats, oat bran, and other soluble fibers can modestly reduce total and low-density lipoprotein (LDL) cholesterol, especially when consumed as part of a diet low in saturated fat. Consuming 56-150 grams of whole oat products such as oatmeal and oat bran, containing 3.6-10 grams of soluble fiber daily, can significantly lower total and LDL cholesterol levels. For each gram of soluble fiber consumed, total cholesterol decreases by about 1.4 mg/dL and LDL by about 1.2 mg/dL. Eating 3-10 grams of soluble fiber daily can reduce total cholesterol by about 4-14 mg/dL (4976,4977,5786,5788,5792,5794,5795,8521,107749,113488,113495). For example, eating 3 bowls of oatmeal (28 gram servings) daily, providing a total of 3 grams of soluble fiber daily, can decrease total cholesterol by about 5 mg/dL (5788). However, consuming more than 10 grams of soluble fiber daily doesn't seem to increase effectiveness (5788). A meta-analysis comparing the effects of oats and isolated beta-glucans shows that both products similarly impact lipid profiles, suggesting that the bioactive component of oats are beta-glucans (113488). Oat bran products, such as oat bran muffins and oat bran flakes, may vary in their ability to lower cholesterol, depending on the total soluble fiber content and other dietary variables (6188). Whole oat products might be more effective for lowering LDL and total cholesterol than foods containing oat bran plus soluble fiber (10145). Although oats are shown to lower total and LDL cholesterol, a meta-analysis and a small clinical study in adults with and without dyslipidemia shows that consuming oatmeal or oat products does not reduce triglycerides or increase high-density lipoprotein (HDL) cholesterol when compared with controls (113488,113495).

POSSIBLY EFFECTIVE

• Diabetes. A diet rich in whole grains, such as oats, may help prevent diabetes or improve blood glucose control in patients with type 1, type 2, or gestational diabetes. Details: Population research shows that for every 16 gram daily serving of whole grains, including oats, there is a 7% to 11% lower risk of developing type 2 diabetes (100622). There is also evidence that consuming oats can decrease blood glucose and insulin levels, as well as lipid levels, in patients with diabetes. The glycemic effects of oats depend on the level of processing of the oat products. Consuming intact oat kernels or thick-cut oats (>0.6 mm) reduces postprandial blood glucose and insulin, but consuming thin-cut, or "quick", oats has no effect (105536). Clinical research shows that consuming oats and oat bran for 4-8 weeks decreases pre-prandial blood glucose, 24-hour plasma glucose, glycated hemoglobin (HbA1c), insulin levels, and low-density lipoprotein (LDL) cholesterol in people with type 2 diabetes (4980,4982,6266,103345). Various doses have been used, including 3 grams of soluble fiber daily, or bread providing 34 grams of total fiber daily (9 grams of soluble fiber) (4961,4980). Additional clinical research in obese adults with type 2 diabetes shows that eating whole grain oats 50-100 grams daily in place of other carbohydrates reduces postprandial blood glucose by 19-27 mg/dL when compared with other carbohydrates in a healthy diet. After 1 year, the groups consuming 50 grams and 100 grams of oats had an additional 0.48% and 0.64% reduction in HbA1c, respectively, when compared with the regular healthy diet group (97520). There is also some evidence that consuming oats 50 grams daily, containing 25 grams of soluble fiber, might be more effective for improving glycemic control and decreasing hyperinsulinemia than the standard moderate fiber diet recommended by the American Diabetes Association (ADA) (6266). Oats have also been evaluated in adolescents with type 1 diabetes. One very small clinical study shows that taking 50 grams of a specific oat product (Betaglucare), providing beta-glucans 6 grams, in three divided doses daily for one week is beneficial for glycemic control and variability when compared with a standard diet without beta-glucans or with taking only 25 grams of the product daily. Maximal, mean, and pre- and post-meal blood glucose levels were modestly lower, and minimal blood glucose levels were modestly higher. Most measures of glycemic variability were statistically different, although there were no differences in the duration of hypoglycemia or hyperglycemia between groups (105261). Oats have also been evaluated in patients with gestational diabetes. A randomized, controlled trial shows that taking 30 grams of a specific oat bran product (OAB; Golden Light Cup Company) orally twice daily at lunch and dinner for 4 weeks improves mean fasting blood glucose and two-hour postprandial glucose when compared with a control group. After 4 weeks, the mean fasting blood glucose and 2-hour postprandial glucose in the treatment group were 85 mg/dL and 104 mg/dL, respectively, compared with 93 mg/dL and 117 mg/dL, respectively, in the control group (107751). The validity of this study is limited by the short treatment duration and lack of follow-up.
• Gastric cancer. A diet rich in soluble fiber, such as that found in oats, might reduce the risk of gastric cancer. Details: Observational research has found that consuming a diet that includes cereal fiber, such as oats and oat bran, might reduce the incidence of gastric cancer (10435).

POSSIBLY INEFFECTIVE

• Colorectal cancer. Regular consumption of oats does not seem to reduce the risk of colorectal cancer. Details: Observational research has found that consuming oat bran or oats orally doesn't seem to reduce the risk of colon cancer. Additionally, consuming fiber, including oat-bran fiber, is not associated with a reduction in the risk for recurrence of colorectal adenomas (4820,5104).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Acne. Although there is interest in using topical oats for acne, there is insufficient reliable information about the clinical effects of oats for this purpose.
• Anxiety. Although there is interest in using oral oats for anxiety, there is insufficient reliable information about the clinical effects of oats for this purpose.
• Atopic dermatitis (eczema). Topical colloidal oatmeal cream may be beneficial in patients with atopic dermatitis. Details: Preliminary clinical research shows that applying a cream containing colloidal oatmeal 1% daily for 2 weeks moderately reduces the severity of atopic dermatitis when compared with baseline (103344). The validity of this finding is limited by the lack of a comparator group. Other research suggests that colloidal oatmeal may be beneficial when used in combination with topical steroids. Clinical research shows that the benefits obtained from applying an ointment containing fluocinolone 0.025% to the hands for 2 weeks were better maintained in the patients who also used a cream containing colloidal oatmeal 1% during this time period and for an additional 4 weeks when compared with patients using fluocinolone and the cream base without colloidal oatmeal. Quality of life was also improved in the patients using colloidal oatmeal (103340).
• Breast cancer. Observational research suggests that regular oatmeal intake may be associated with reduced mortality from breast cancer. Details: Population research in postmenopausal patients has found that those who have eaten 50 grams of oatmeal daily prior to a breast cancer diagnosis have a 20% reduced risk of all-cause mortality in the 7 years following the diagnosis when compared with patients who have not eaten oatmeal. However, no benefit was seen when post-diagnostic oatmeal intakes were examined (103343).
• Burns. Although there is interest in using topical oats for burns, there is insufficient reliable information about the clinical effects of oats for this purpose.
• Chronic fatigue syndrome (CFS). Although there is interest in using oral oats for CFS, there is insufficient reliable information about the clinical effects of oats for this purpose.
• Cognitive function. It is unclear if oral oats are beneficial in healthy adults with mild memory impairment. Details: Preliminary clinical research in healthy middle-aged adults with self-reported memory decline shows that consuming a specific wild green-oats extract (Neuravena, Frutarom) 800 mg as a single dose improves overall speed, but not overall accuracy, of cognitive performance when compared with placebo. However, a higher dose of 1600 mg was ineffective (97519).
• Dry skin. It is unclear if applying lotion containing colloidal oat extract improves dry skin to a greater extent than other lotion products. Details: Preliminary clinical research shows that applying a lotion containing colloidal oat extract (Aveeno Active Naturals Skin Relief 24Hr Moisturizing Lotion, Johnson & Johnson) twice daily for 2 weeks improves itchiness, cracking, scaling, dryness, and roughness when compared to baseline in females with dry skin (91458). Additional preliminary clinical research shows that applying a colloidal oatmeal lotion to the legs twice daily for three weeks reduces skin dryness and improves skin integrity when compared to baseline in adults with dry skin (97518). The validity of these findings is limited by the lack of a comparator group.
• Exercise-induced muscle soreness. It is unclear if oral oats are beneficial for exercise-induced muscle soreness. Details: A small clinical trial shows that eating two cookies containing oat flour 60 grams daily for 8 weeks reduces muscle soreness 48 or 72 hours after downhill running when compared with baseline (103341).
• Fat redistribution syndrome. It is unclear if oral oats are beneficial for fat redistribution syndrome. Details: Consumption of a high fiber diet, including oats, with adequate energy and protein might prevent fat deposition in patients with HIV. A one-gram increase in total dietary fiber may decrease the risk of fat deposition by 7% (12517).
• Gallbladder disease. Although there is interest in using oral oats for gallbladder disease, there is insufficient reliable information about the clinical effects of oats for this purpose.
• Hypertension. It is unclear if oral oats are beneficial for hypertension. Details: A meta-analysis of 21 clinical studies in healthy adults and those with a variety of metabolic conditions including hypertension shows that consumption of oat products reduces systolic blood pressure (SBP) by 3 mmHg but has no effect on diastolic blood pressure (DBP) when compared with control. Subgroup analysis suggests that consuming oat products reduces SBP by 10 mmHg in patients with hypertension at baseline. An additional subgroup analysis suggests that consuming at least 5 grams of beta-glucan-enriched oats daily or consuming oats for a duration at least 8 weeks reduces SBP and DBP (113494). Observational research has found that consumption of oats as oatmeal or oat cereal does not seem to reduce DBPor SBP in males with minor elevations in blood pressure or patients with dyslipidemia (2956,113495). A randomized, controlled trial in patients with stage 1 hypertension receiving dietary guidance shows that taking 30 grams of oat bran, providing 8.9 grams of dietary fiber, once daily with breakfast or in between meals for 3 months improves various blood pressure measures when compared with dietary guidance alone. After 3 months of treatment, 24-hour maximum SBP and DBP decreased by 14 mmHg and 11 mmHg, respectively, and office SBP and DBP decreased by 15 mmHg and 10 mmHg, respectively. Oat consumption may also have impacted antihypertensive medication use. Two patients in the control group increased doses of antihypertensive medications, whereas 6 patients in the treatment group decreased doses and 1 patient discontinued use (107750). The effect of oral oat bran on patients with stage 2 hypertension or pre-hypertension is unknown.
• Irritable bowel syndrome (IBS). Although there is interest in using oral oats for IBS, there is insufficient reliable information about the clinical effects of oats for this purpose.
• Metabolic syndrome. Limited research suggests that oats may not be beneficial for metabolic syndrome. Details: Preliminary clinical research in adults with metabolic syndrome shows that adding oat bran 40 grams daily for 6 weeks to a low-calorie diet does not reduce the incidence of metabolic syndrome. Oat bran also does not improve body weight, blood pressure, low-density lipoprotein (LDL) cholesterol, triglycerides, or blood glucose levels when compared with a low-calorie diet alone in patients with metabolic syndrome (103342).
• Osteoarthritis. Although there is interest in using oral oats for osteoarthritis, there is insufficient reliable information about the clinical effects of oats for this condition.
• Pruritus. Applying oat lotion topically may improve some types of pruritus. Details: Preliminary clinical research shows that applying an oat lotion (Espanol) twice daily for up to 2 weeks can decrease itching intensity by about 20% when compared to baseline in patients with pruritus associated with chronic kidney disease (uremic pruritus). This decrease is similar to the effects of applying vinegar 5% solution or taking hydroxyzine 10 mg orally. However, applying the oat lotion does not appear to decrease the frequency of itching (91457).
• Psoriasis. Although there is interest in using topical oats for psoriasis, there is insufficient reliable information about the clinical effects of oats for this purpose.
• Rheumatoid arthritis (RA). Although there is interest in using oral oats for RA, there is insufficient reliable information about the clinical effects of oats for this purpose.
• Stroke. It is unclear if oral oats are beneficial for reducing the risk of stroke. Details: Population research suggests that consuming oatmeal for breakfast once weekly might reduce the incidence of stroke by a small amount when compared with consuming white bread or eggs for breakfast (103337).
• Ulcerative colitis. Oral oats have only been evaluated in combination with other ingredients; their effect when used alone is unclear. Details: Preliminary clinical research shows that taking a specific oat-based product (Profermin, Nordisk Rebalance) containing fermented oat flour, Lactobacillus plantarum, barley malt flour, and lecithin, 250 mL orally twice daily for 8 weeks, reduces disease activity and increases remission in about two-fold more patients with relapsing ulcerative colitis, when compared with treatment with a specific nutritional beverage (Fresubin Original, Fresenius Kabi) (90271).
• Wound healing. Although there is interest in using topical oats for wound healing, there is insufficient reliable information about the clinical effects of oats for this purpose. More evidence is needed to rate oats for these uses.

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POSSIBLY EFFECTIVE

• Hypercholesterolemia. Most clinical research shows that oral pectin at a dose of 15 grams daily can slightly lower total cholesterol and low-density lipoprotein (LDL) cholesterol levels in patients with hypercholesterolemia. Details: While some small studies in patients with or without hypercholesterolemia suggest that pectin 1-12 grams daily for up to 12 weeks does not reduce lipid levels (2215,2217), other research in patients with hypercholesterolemia shows that taking pectin 15 grams daily for 4 weeks consistently reduces total cholesterol and LDL cholesterol by around 7% to 10% when compared with baseline or placebo (2214,2216,92473). Some forms of pectin might lower cholesterol levels better than others. Pectin with a higher molecular weight and higher degree of esterification appears to be the most effective (92473). A larger clinical study also shows that taking 20 grams of pectin and guar gum, along with small amounts of insoluble fiber, reduces total cholesterol by nearly 8% and LDL cholesterol by nearly 11%, but does not improve high-density lipoprotein (HDL) cholesterol or triglycerides, when compared with placebo (12547).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Colorectal cancer. Although there has been interest in using oral pectin for the prevention of colorectal cancer, there is insufficient reliable information about the clinical effects of pectin for this purpose.
• Diarrhea. It is unclear if oral pectin is beneficial in children with persistent diarrhea. Details: A small clinical study in children aged 5-12 months in developing nations with persistent diarrhea shows that taking pectin 4 grams/kg reduces the duration of diarrhea and vomiting, and reduces the need for oral rehydration solution and intravenous fluid, when compared with a rice-diet control (12575). Pectin has also been evaluated in combination with other ingredients. One clinical study in children aged 6 months to 6 years with acute diarrhea shows that taking a combination of apple pectin and chamomile (Diarrhoesan, Dr. Loges + Co. GmbH) for up to 5 days reduces the frequency of stools by day 3 by about 1.36-fold when compared with placebo, with improvements maintained through day 5. This combination product was given hourly up to a maximum dose of 50 mL in children 6-12 months of age, 60 mL in children 1-3 years of age, and 80 mL in children 4-6 years of age (19705). It is unclear if these findings are due to pectin, chamomile, or the combination.
• Gastroesophageal reflux disease (GERD). It is unclear if oral pectin is beneficial in children with GERD. Details: A small clinical study in children with GERD and cerebral palsy shows that adding pectin to enteral nutrition in a 1:2 ratio for 4 weeks might reduce some symptoms of GERD. The number of vomiting episodes per week was reduced by 60% and the frequency of coughing/wheezing was reduced by 76% for children given the pectin diet when compared with those given a non-pectin diet (92476).
• Impaired glucose tolerance (Prediabetes). It is unclear if oral pectin is beneficial in patients with impaired glucose tolerance. Details: A small clinical study in middle-aged patients with impaired glucose tolerance or impaired fasting glucose shows that drinking 400 mL of a beverage containing 40 grams/L of sugar beet pectin in two divided doses daily for 12 weeks does not improve fasting or postprandial plasma glucose concentrations or serum lipid levels when compared to baseline (34118).
• Irritable bowel syndrome (IBS). Although there has been interest in using oral pectin for IBS, there is insufficient reliable information about the clinical effects of pectin for this purpose.
• Mercury toxicity. It is unclear if oral pectin is beneficial in patients with mercury toxicity. Details: A small clinical study in children with mercury poisoning shows that taking pectin 2.5 grams daily for 21 days and then 5 grams daily for 39 days increases mercury excretion in the urine, decreases the duration of mercury toxicity, and improves psychological symptoms when compared to baseline (31657). The validity of these findings is limited by the lack of a comparator group.
• Niacin-induced flushing. It is unclear if oral pectin is beneficial for the prevention or management of niacin-induced flushing. Details: A small clinical study shows that taking apple pectin 2 grams 30 minutes prior to taking niacin extended-release 1000 mg reduces the duration of flushing by about 35 minutes when compared with placebo. However, apple pectin does not reduce the incidence of flushing, the time to flush, or the maximum severity of flushing (92477).
• Peptic ulcers. It is unclear if oral pectin is beneficial for the prevention of peptic ulcers. Details: A small clinical study in patients with recently healed duodenal ulcers shows that taking apple pectin 10 grams twice daily for 6 months does not reduce the recurrence of duodenal ulcers when compared with placebo (31697).
• Prostate cancer. It is unclear if oral pectin is beneficial in patients with prostate cancer. Details: Two small clinical studies in patients with prostate cancer show that taking a specific modified citrus pectin product (Pectasol, Econugenics) 4.8 grams three times daily following prostatectomy, radiation, or cryosurgery for up to one year slows disease progression and increases the time to prostate specific antigen (PSA) doubling when compared to baseline (15020,108525). The validity of these findings is limited by the lack of a comparator group.
• Radiation exposure. Although there has been interest in using oral pectin to minimize exposure to environmental radiation, there is insufficient reliable information about the clinical effects of pectin for this purpose. More evidence is needed to rate pectin for these uses.

(Read more about PECTIN)

LIKELY SAFE ...when used orally and appropriately in food amounts (4960,4969,5792,5797). Oat bran has Generally Recognized as Safe (GRAS) status in the US (4912). Whole grain oats 50-100 grams daily have been used for up to 1 year without serious adverse effects (97520).

POSSIBLY SAFE ...when used topically and appropriately (12). Lotion containing colloidal oat 1% has been used topically without adverse effects for up to 6 weeks (97518,103340). There is insufficient reliable information available about the safety of oats when used orally in medicinal amounts.

PREGNANCY AND LACTATION: LIKELY SAFE
when used orally in food amounts (5792,5797).

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

POSSIBLY SAFE ...when used orally in amounts greater than those typically found in food. Pectin 4.8 grams three times daily has been used for up to one year without serious adverse effects (12547,15019,15020,92481,108525).

CHILDREN: POSSIBLY SAFE
when used orally in amounts greater than those found in food, short-term. Pectin 4 grams/kg has been used daily for up to 7 days without reports of serious adverse effects (12575,19705).

PREGNANCY AND LACTATION: LIKELY SAFE
when used in amounts commonly found in foods. Pectin has Generally Recognized as Safe (GRAS) status in the US (4912).

PREGNANCY AND LACTATION: POSSIBLY SAFE
when used orally in medicinal amounts (12577).

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ANTIDIABETES DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, oats may have additive effects with antidiabetic agents and might increase the risk of hypoglycemia.  Details Consuming oats can decrease blood glucose in patients with diabetes (4980,4982,6266,103345). In those who require insulin, taking oats 100 grams daily for 2 days reduces the insulin dose required to achieve metabolic control (103336).

INSULIN Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Concomitant use of oats and insulin might increase the risk of hypoglycemia.  Details In patients with insulin-dependent type 2 diabetes, taking oats 100 grams daily for 2 days reduces the insulin dose required to achieve metabolic control (103336).

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DIGOXIN (Lanoxin) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, pectin might reduce the absorption of digoxin, potentially decreasing its effectiveness.  Details A small clinical study shows that taking digoxin with a kaolin-pectin suspension reduces the absorption of digoxin by about 62% (2212). It is unclear if these effects are due to pectin, kaolin, or the combination.

LOVASTATIN (Mevacor) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, pectin might reduce the absorption of lovastatin, potentially decreasing its effectiveness.  Details Case reports suggest that concomitant use of pectin and lovastatin might reduce the cholesterol-lowering effect of lovastatin, possibly due to reduced intestinal absorption of lovastatin (615).

TETRACYCLINE ANTIBIOTICS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, pectin might reduce the absorption of tetracycline antibiotics, potentially decreasing their effectiveness.  Details A small clinical study shows that taking tetracycline with bismuth subsalicylate in a kaolin-pectin suspension reduces the absorption of tetracycline by about 34% (2213). It is unclear if these effects are due to pectin, kaolin, bismuth subsalicylate, or the combination.

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General ...Orally, oats are well tolerated.
Most Common Adverse Effects:
Orally: Abdominal distension, bloating, flatulence, and unpleasant taste.
Topically: Burning, contact dermatitis, itching, and redness.

Dermatologic ...Topically, oat-containing preparations can cause contact dermatitis (12515). Redness, burning, and itchiness have also been reported (103340).

Gastrointestinal ...When consumed orally, oats provide fiber. Increasing fiber in the diet can cause flatulence, bloating, abdominal distention, and unpleasant taste. To minimize side effects, doses should be slowly titrated to the desired level. These adverse effects usually subside with continued use (12514).
In patients who have difficulty chewing food, or those with conditions that decrease small bowel motility, oat bran may cause bezoars (concretions) and intestinal obstruction. Oats and oat bran are unlikely to cause obstruction without other causative factors (4979,4985).

Immunologic ...In a case report, a 45-year-old male developed acute generalized urticaria, facial angioedema, and dyspnea immediately after consuming oat flour. The reaction resolved after emergency care for anaphylaxis. Further investigation revealed an IgE-mediated hypersensitivity reaction to oat proteins (113490).

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General ...Orally, pectin seems to be well tolerated.
Most Common Adverse Effects:
Orally: Diarrhea, gas, loose stools, and mild cramps.
Serious Adverse Effects (Rare):
All routes of administration: Allergic reactions, including anaphylaxis, in sensitive individuals.

Gastrointestinal ...Orally, pectin alone or in combination with guar gum and insoluble fiber can cause gastrointestinal adverse effects such as mild cramps, diarrhea, gas, and loose stools (12547,15020,92473).

Immunologic ...Orally and topically, pectin may cause allergic reactions in sensitive individuals. In one case, a 7-year-old boy with a history of oral allergy syndrome after consuming a pectin-containing beverage experienced anaphylaxis after taking a citrus bath containing pectin. Allergy testing confirmed sensitivity to pectin (106928).

Pulmonary/Respiratory ...The occupational inhalation of pectin dust can cause asthma (580,581,582,583,584).

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