Complete Protein Diet Bars by Optimum Nutrition

LIKELY EFFECTIVE

• Atopic dermatitis (eczema). Consuming casein peptide as part of formula with or without breastmilk for up to 6 months reduces the risk of atopic dermatitis in infants. Details: Clinical research shows that feeding infants a casein peptide-based formula (Nutramigen or Progestimil, Mead Johnson), with or without breastmilk for 4-6 months, reduces the risk for atopic dermatitis during the first 9-24 months of life by 52% to 73% when compared to cow's milk formula (91655,91656,91658). The benefits of casein peptides appear to be most significant in infants with a family history of atopy (91655,91656). Additionally, the benefit of using a casein peptide-based formula during the first 4 months of life persists into childhood, with a 29% reduced risk of developing atopic dermatitis at 6 years of age when compared to cow's milk formula (91659,91660). Clinical research also shows that casein peptide formula is equally effective to hydrolyzed whey protein formula for reducing the risk for atopic dermatitis in infants (91657,91658,91659,91660,91661).
• Atopic disease. Consuming casein peptide as part of formula during the first 4 months of life reduces the risk of atopic disease in infants with a family history of atopy. The benefits of casein peptide in infants without a family history of atopy is unclear. Details: Clinical research in infants with a family history of atopy shows that taking a casein peptide-based formula (Nutramigen, Mead Johnson) during the first 4 months of life, or after weaning from breastmilk, reduces the risk for atopic manifestations during the first 12-18 months of life by 39% to 44% when compared with cow's milk formula (91656,91658). This benefit persists over time, with a 20% reduced risk for developing atopic disease at 6 years of age when compared to cow's milk formula (91660). However, it may not be beneficial in children without a family history of atopy. One large, ancillary clinical study in children at increased risk for development of type 1 diabetes, but not specifically at risk for atopy, shows that using an extensively hydrolyzed casein peptide formula (Nutramigen, Mead Johnson) in infancy for up to 6-8 months does not prevent persistent asthma, allergic rhinitis, or atopic dermatitis development when compared with using a conventional formula containing 80% intact cow's milk protein and 20% hydrolyzed milk protein (Enfamil, Mead Johnson). The validity of these findings is limited by the patient population and the unclear duration of follow up (106564).
• Food allergies. Consuming casein peptide formulas is a safe alternative to cow's milk in children with cow's milk allergy. Details: Clinical research shows that specific casein peptide formulas are a safe and well-tolerated alternative for children with documented allergy to cow's milk. Evaluated formulas include Alimentum (Abbot Laboratories), Damira 2000 (Nutrition & Sante S.L.), Frisolac Allergycare (Friesland Nutrition), and Nutramigen (Mead Johnson) (91663,91664,91665,111439). A cost-effective analysis in children with cow's milk allergy also suggests that using casein peptide-based formula is cost-effective dominant and reduces other allergic manifestations when compared with soy-based formula (111438).

POSSIBLY EFFECTIVE

• Colic. Clinical research shows that consuming casein peptides as part of formula reduces crying, short-term, in infants with colic. Details: Clinical research in infants with colic shows that replacing cow's milk formula with a specific casein peptide formula (Nutramigen, Mead Johnson) significantly reduces crying and colic when compared with cow's milk formula. However, this effect appears to diminish after more than four days of use (91262). Preliminary clinical research shows that consuming specific casein peptide formulas (Alimentum, Abbot Laboratories; Nutramigen, Mead Johnson) for 7 days reduces daily crying time by up to 5 hours and reduces crying intensity when compared with baseline in infants with colic (91264). The validity of this finding is limited by the lack of a comparator group.
• Diabetes. Consuming casein peptides with carbohydrates may be beneficial for reducing postprandial glucose and insulin levels in adults with type 2 diabetes. Casein peptides have also been evaluated for the prevention of type 1 diabetes in infants, with inconclusive results. Details: In adults with type 2 diabetes, casein protein may improve postprandial glucose levels. Most clinical research shows that consuming casein peptides in conjunction with a carbohydrate bolus increases postprandial insulin response by 26% to 300% and reduces postprandial glucose levels by 5% to 28% when compared with consuming carbohydrates alone (91276,91295,91297,91299). These effects seem to persist with casein peptide doses as low as 12 grams daily, but not 6 grams daily (91300). Preliminary clinical research also shows that adding leucine 5 grams or 0.1 grams/kg to casein peptides increases postprandial insulin levels by 52% to 200%, reduces postprandial glucose levels by 5% to 12%, and improves 24-hour glucose levels by 11% when compared with consuming carbohydrates alone (91296,91297). However, some preliminary clinical research shows that consuming casein peptides 0.4 grams/kg with each meal for one day does not improve glycemic control (91298). These differing outcomes might be related to the forms of carbohydrates used, which include carbohydrate boluses and carbohydrate-containing meals. Additionally, the evidence for the effects of intact casein protein, as opposed to casein peptides, on postprandial insulin and glucose levels is conflicting (91276,91299). Clinical research in infants 6-8 months of age who are genetically predisposed to type 1 diabetes shows that administering a specific casein peptide-based formula (Nutramigen, Mead Johnson) in place of breastmilk decreases the development of one or more diabetes-associated auto-antibodies when compared with cow's milk formula. However, there was no difference in type 1 diabetes incidence after 10 years. This study was not powered to detect a difference in this outcome (91675).
• Hypertension. The casein peptides isoleucine-proline-proline (IPP) and valine-proline-proline (VPP), sometimes referred to as lactotripeptides, can modestly reduce blood pressure in patients with hypertension. Lower doses given for shorter durations seem to produce greater effects, and the effects may be more pronounced in Japanese patients than in European patients. Details: The most comprehensive meta-analysis to-date in patients with hypertension shows that taking casein peptides reduces systolic blood pressure (SBP) by 3 mmHg and diastolic blood pressure (DBP) by 1.5 mmHg. The average dose of casein peptides was 10.5 mg daily, including IPP 5.2 mg and VPP 5.3 mg daily, for about 8 weeks. However, there may be an inverse dose-response relationship; daily doses of casein peptides of 10 mg or less, lasting for 8 weeks or less, reduced blood pressure to a greater degree when compared with higher doses given for longer durations. Furthermore, casein peptides produced by fermentation resulted in modestly greater blood pressure reduction when compared with casein peptides produced by enzymatic hydrolysis (103765). Patient ethnicity may also play a role in the magnitude of effect. Other meta-analyses show a 1-6 mmHg reduction in SBP and 0.6-1.5 mmHg reduction in DBP when compared with control (103762,103763,103765,111437). A small clinical study in healthy Japanese males and postmenopausal adults with prehypertension shows that supplementation with casein peptides IPP 2 mg and VPP 1.4 mg daily for 8 weeks reduces home-monitored 7-day mean DBP, but not SBP, by 0.9 mmHg, compared with an increase of 1.2 mmHg in those receiving placebo (106565). Although findings are positive overall, the validity of the above meta-analysis, as well as older or less comprehensive analyses, is limited by the poor reporting and methodology of the included studies (103763,103765,103770,103772). Some limited research in patients with metabolic syndrome shows conflicting blood pressure lowering effects. A small clinical study shows that taking IPP/VPP (Calpis Co., Ltd.) 10.2 mg in the morning before breakfast daily for 4 weeks lowers 24-hour ambulatory systolic blood pressure by 2 mmHg, but not diastolic blood pressure, when compared with placebo (103764). However, another study shows that taking casein peptides 5-25 mg daily with plant sterols 2 grams daily orally for 12 weeks does not reduce blood pressure when compared with placebo (103767). Notably, this study was not adequately powered to detect small changes in blood pressure.
• Neonatal jaundice. Clinical research suggests that consuming casein peptide reduces the risk of jaundice in neonates. Details: Preliminary clinical research shows that feeding newborns a specific casein peptide formula (Nutramigen, Mead Johnson) for 3 weeks reduces the risk of jaundice when compared with whey-predominant formula (91642) or human milk (91642,91651). Other preliminary clinical research in breastfed newborns shows that taking 5 mL of casein peptide formula, created by enzymatic hydrolysis, 6 times daily for 7 days decreases transcutaneous bilirubin levels when compared with breastfeeding alone (91643).

POSSIBLY INEFFECTIVE

• Asthma. Consuming casein peptide does not appear to reduce the risk of asthma in infants. Details: Most clinical research shows that feeding infants a casein peptide-based formula (Nutramigen or Progestimil, Mead Johnson), with or without breastmilk for 4 months, does not reduce the risk for asthma in the first 4 months to 6 years of life in children with a family history of atopy (91655,91659,91660). However, one preliminary clinical study shows that feeding infants Nutramigen beginning at about 3.8 months of age decreases wheezing by 61% compared to cow's milk formula; the incidence of asthma was not evaluated (91656).
• Infant development. Consuming casein peptide does not appear to affect growth or development in healthy infants, or in premature or low-birth weight infants. Details: Most clinical research shows that using casein peptide-predominant formula for 6 weeks to 6 months in premature, low-birth weight, or healthy infants does not affect growth when compared with breast milk, whey protein-based formula, rice hydrolysate formula, cow's milk formula, or amino acid-based formula (86085,91644,91672,91673). Additionally, feeding infants a specific casein peptide formula (Nutramigen, Mead Johnson) for 4 months does not affect growth at 6 or 10 years when compared with whey protein-based formula, cow's milk formula, or breast milk (86085,91644). However, clinical research suggests that a casein peptide-based formula might be beneficial in infants with cow's milk allergy. One study in this population shows that casein peptide-based formula significantly increases growth from 6-12 months of age when compared with soy-based formula (91672).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Acne. It is unclear if oral casein peptides are beneficial in patients with acne. Details: Preliminary clinical research in adults with moderate to severe acne shows that taking a specific casein peptide (Lactium) 150 mg orally daily for 84 days does not reduce acne lesion count when compared with control. However, the study may have been inadequately powered to detect a difference between groups (111436).
• Aging skin. It is unclear if oral casein peptides are beneficial in patients with aging skin. Details: A small clinical study in healthy, normotensive older Japanese adults shows that taking casein peptides isoleucine-proline-proline (IPP) and valine-proline-proline (VPP) orally once daily for 48 weeks reduces facial pigmentation area by about 15%, compared with an increase of about 6% in patients taking placebo (106563).
• Anxiety. Although there has been interest in using oral casein peptides for anxiety, there is insufficient reliable information about the clinical effects of casein peptides for this purpose.
• Athletic performance. It is unclear if oral casein peptides are beneficial for athletic performance. Details: Preliminary clinical research in overweight male police officers shows that taking casein peptides 1.5 grams/kg orally daily in two divided doses for 12 weeks, in conjunction with resistance training, decreases body fat percentage by 3%, increases lean body mass by 2 kg, and improves chest, shoulder, and leg press strength by around 30% when compared with whey protein (85648).
• Cancer. Although there has been interest in using oral casein peptides for cancer, there is insufficient reliable information about the clinical effects of casein peptides for this purpose.
• Diarrhea. It is unclear if oral casein peptides are beneficial in patients with diarrhea. Details: Preliminary clinical research in male children with persistent diarrhea shows that consuming a casein peptide-based diet during hospitalization is less effective for reducing stool output than a yogurt-based diet (91648).
• Epilepsy. Although there has been interest in using oral casein peptides for epilepsy, there is insufficient reliable information about the clinical effects of casein peptides for this purpose.
• Exercise-induced muscle soreness. It is unclear if oral casein peptides are beneficial in patients with exercise-induced muscle soreness. Details: Preliminary clinical research in male cyclists shows that drinking 200 mL of a carbohydrate beverage containing 1.8% casein peptides every 5 km followed by 500 mL after cycling completion reduces exercise-induced muscle soreness and improves late-exercise time-trial performance when compared with drinking a carbohydrate beverage alone (91256).
• Fatigue. Although there has been interest in using oral casein peptides for fatigue, there is insufficient reliable information about the clinical effects of casein peptides for this purpose.
• Hyperlipidemia. Low quality research suggests that oral casein peptides are not beneficial in patients with hyperlipidemia. Details: A meta-analysis of randomized trials in subjects with and without hyperlipidemia shows that using casein peptide-based diets for 1-48 weeks does not improve low-density lipoprotein cholesterol, high-density cholesterol, or triglyceride levels when compared with control (111437).
• Insomnia. It is unclear if oral casein peptides are beneficial in patients with insomnia. Details: A small clinical study in Korean patients with poor sleep quality shows that taking a specific product (Lactium, Ingredia) containing bovine alpha-s1 casein peptides 300 mg one hour before bedtime for 4 weeks modestly improves sleep efficiency based on subjective reports and actigraphy measures when compared with placebo (103774). Casein peptides have also been studied as part of combination products. A small clinical study in adults with insomnia or disturbed sleep patterns shows that a specific product (RLX2; LiveLife Biosciences AG) containing a specific casein peptide, alpha-s1-casein tryptic hydrolysate, 150 mg, and L-theanine 50 mg, taken one hour before bedtime for 4 weeks, increases sleep duration by 45 minutes and improves habitual sleep efficiency and daytime dysfunction when compared with baseline. However, it does not affect blood pressure, heart rate, or cortisol levels (108556). It is unclear if these effects are due to L-theanine, alpha-s1-casein tryptic hydrolysate, or the combination.
• Physical performance. It is unclear if oral casein peptides are beneficial for physical performance. Details: Preliminary clinical research in healthy older males shows that taking casein peptides 10 grams before and after resistance training for 8 weeks does not improve strength or body composition when compared with placebo (91255).
• Stress. Although there has been interest in using oral casein peptides for stress, there is insufficient reliable information about the clinical effects of casein peptides for this purpose. More evidence is needed to rate casein peptides for these uses.

(Read more about CASEIN PEPTIDES)

POSSIBLY EFFECTIVE

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

POSSIBLY INEFFECTIVE

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

INSUFFICIENT RELIABLE EVIDENCE to RATE

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

(Read more about COCOA)

LIKELY EFFECTIVE

• Constipation. Rectal glycerol is beneficial in children and adults with constipation. Details: Glycerol rectal suppositories and enemas are approved by the US Food and Drug Administration (FDA) for over-the-counter use to treat occasional constipation in adults and children at least 2 years of age (15).

POSSIBLY EFFECTIVE

• Athletic performance. Oral glycerol may improve hydration during exercise, but clinical studies evaluating glycerol for improving measures of athletic performance are limited and conflicting. Details: Several clinical studies show that glycerol increases serum osmolality and improves hydration status during exercise (2475,2476,93757,93760,93761,93765). One meta-analysis, including 14 studies and 99 patients, shows that glycerol-induced hyperhydration increases body water by approximately 2.5-fold when compared with water-induced hyperhydration (93757). Also, taking glycerol along with table salt 7.5 grams per liter fluid seems to improve hydration status when compared withg glycerol alone (99162). Research regarding the effects of glycerol on thirst, comfort, temperature regulation, sweating, and heart rate is conflicting (2475,2476,93760,99162). While glycerol may improve hydration status during exercise, it is unclear whether it can improve measures of athletic performance. An early meta-analysis including a total of 36 athletes shows that taking glycerol increases endurance performance by 2.6%. Although this is a small difference, it might be considered meaningful to athletes (93757). Some small clinical studies in athletes suggest that glycerol increases endurance and time to exhaustion, with no effect on heat regulation (2475,2479,93764). However, other small studies suggest that glycerol does not reduce perceived exhaustion or improve exercise performance (2476,93760). Also, glycerol has not been shown to increase time to exhaustion in triathletes (2492). When used to improve athletic performance, glycerol is most often taken at doses of 1-1.5 gram/kg in conjunction with approximately 1.5 L of fluid, 60-120 minutes before competition, and in some cases continued during the competition (2475,93757,93760,93764).
• Ichthyosis. Topical application of a specific product containing glycerol and paraffin may improve symptoms of ichthyosis in children. The benefits of topical glycerol alone in these patients is unknown. Details: A large clinical trial in children aged 1 month to 18 years shows that applying a specific product (Dexeryl, Pierre Fabre Laboratoires) containing glycerol 15% and paraffin 10% for 4 weeks reduces symptoms of non-bullous ichthyosis by at least 50% in an additional 17% of children when compared with a placebo cream. Applying this specific product also improves pruritus by an additional 45% when compared with placebo (93756). It is unclear if these findings are due to glycerol, paraffin, or the combination.

POSSIBLY INEFFECTIVE

• Meningitis. Some clinical research suggests that oral glycerol does not reduce the risk of mortality or seizures in adults and children with bacterial meningitis, although it may reduce certain sequelae. Details: A meta-analysis of five low-quality clinical trials including 1,270 patients shows that adjunctive treatment with glycerol as an oral osmotic agent does not reduce the risk of mortality, seizures, or gastrointestinal symptoms in adults and children with acute bacterial meningitis, although it may modestly reduce the risk of deafness and residual neurological deficit in surviving children (99160). Clinical research included in the meta-analysis has used glycerol 1.5 grams/kg every 6 hours in children aged 2 months to 16 years (93762,93763).
• Prematurity. Rectal glycerol does not appear to reduce the time to enteral feeding in premature infants. Details: Glycerol is used as an enema or given by suppository to facilitate the evacuation of meconium in premature infants in order to reduce the time to enteral feeding. However, two meta-analyses of small studies in preterm infants, that include some of the same studies, show that administering glycerol suppositories does not reduce the number of days to full enteral feeds when compared with placebo or no treatment (99166,112003). However, the interpretation of these findings is limited by the heterogeneity of dosages used in the included studies.

LIKELY INEFFECTIVE

• Stroke. Intravenous glycerol may not improve mortality or symptoms in patients with acute ischemic stroke. Details: Several clinical studies show that intravenous administration of glycerol does not improve symptoms of acute stroke (2480,2481,2482,2484,2486). Additionally, one clinical study in elderly patients with acute ischemic stroke shows that while glycerol can improve initial survival, it does not reduce the risk of overall mortality when compared with placebo (2483).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Dandruff. Topical glycerol has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: One clinical trial in adults with dandruff shows that applying a leave-in hair lotion containing glycerol 10%, stearic acid 2.5%, and sunflower seed oil 0.6%, 3 times weekly for 8 weeks, modestly reduces dandruff severity throughout use and for up to one week after the last application when compared with a placebo lotion. The glycerol lotion also reduced total water loss from the scalp by 8% and increased moisturization by 23% (93758). It is unclear if these findings are due to glycerol, other ingredients, or the combination.
• Dry skin. Topical glycerol has only been evaluated in combination with other ingredients for the management of dry skin associated with kidney failure; its effect when used alone is unclear. Details: One small, open-label clinical study in adults with kidney failure and moderate to severe uremic xerosis shows that applying an emulsion containing glycerol 15% and paraffin 10% twice daily for 7 days reduces the severity of xerosis when compared with a placebo emulsion. The glycerol-containing emulsion produces a treatment response in an additional 29% of patients, improves quality of life, and reduces scale density and thickness when compared with placebo (93754). It is unclear if these findings are due to glycerol, paraffin, or the combination.
• Glaucoma. Although there has been interest in using oral glycerol for glaucoma, there is insufficient reliable information about the clinical effects of glycerol for this purpose.
• Intracranial hypertension. Although there has been interest in using intravenous glycerol to reduce intracranial pressure in patients with brain tumors, central nervous system (CNS) trauma, encephalitis, idiopathic intracranial hypertension, meningitis, and Reye syndrome, there is insufficient reliable information about the clinical effects of glycerol for this purpose.
• Meniere disease. It is unclear if intravenous glycerol is beneficial in patients with Meniere disease. Details: A small, uncontrolled clinical study in adults with unilateral, intractable Meniere disease shows that intravenous administration of glycerol 10% at a dose of 0.5 grams/kg once daily for 2 consecutive days, twice monthly for 6 months, reduces the frequency of vertigo attacks and improves quality of life when compared to baseline. Patients reported an average of 3.2 vertigo attacks per month at baseline and 1.2 vertigo attacks per month after 6 months of treatment (106649). The lack of a control group limits the validity of these findings.
• Neonatal jaundice. It is unclear if rectal glycerol improves jaundice-related outcomes in premature infants. Details: A small clinical study in neonates receiving phototherapy for jaundice shows that administering glycerol suppositories has no effect on the duration of phototherapy needed for jaundice treatment, or on bilirubin levels or the rate of bilirubin decline when compared with no glycerol suppositories (99165).
• Obesity. It is unclear if oral glycerol is beneficial in patients who are overweight or obese. Details: One small clinical study in adults on a low-calorie diet shows that taking glycerol 7.5 grams before meals for 6 weeks does not increase weight loss when compared with placebo (2485).
• Otitis externa. Topical glycerol has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: One small clinical study in adults with otitis externa shows that inserting ribbon gauze soaked in glycerol and ichthammol into the ear canal reduces pain and swelling as effectively as the application of antibiotic and steroid drops three times daily (93759). It is unclear if these findings are due to glycerol, ichthammol, or the combination. More evidence is needed to rate glycerol for these uses.

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INSUFFICIENT RELIABLE EVIDENCE to RATE

• Dental plaque. It is unclear if oral or topical gum arabic is beneficial for preventing or treating dental plaque. Details: Preliminary clinical research shows that chewing gum arabic for 10 minutes, five times daily for 7 days, reduces dental plaque when compared with chewing sugar-free gum (30220). Another small clinical study in adults with mild or moderate plaque-induced gingivitis shows that applying half a teaspoon of gum arabic powder to the buccal surface of dentogingivial areas for 5 minutes then rinsing with tap water twice daily for 60 days reduces dental plaque in patients with moderate, but not high, plaque accumulation when compared with placebo (111508). Gum arabic has also been evaluated in combination with other ingredients for this purpose. A small clinical study shows that applying a pea-size amount of gel containing gum arabic, barleria, medlar, terminalia, and melia (Gum Tone Gel, Charak Pharma Pvt Ltd.) after brushing for 6 weeks decreases plaque severity when compared with placebo. The gel is similar in effectiveness to chlorhexidine 1% gel (92887). However, it's unclear if these findings are due to gum arabic, other ingredients, or the combination.
• Diabetes. It is unclear if oral gum arabic is beneficial in patients with diabetes. Details: Clinical research in adults with type 2 diabetes who are taking oral antidiabetes medications shows that taking gum arabic powder 30 grams daily in the morning for 3 months modestly reduces fasting blood glucose and glycated hemoglobin (HbA1c) when compared with baseline. Gum arabic also modestly reduces low-density lipoprotein (LDL) cholesterol levels, body mass index, and hip circumference, but not waist circumference or blood pressure, when compared with baseline (98700,99098). The validity of these findings is limited by the lack of a comparison to the placebo group.
• Gingivitis. It is unclear if topical gum arabic is beneficial in patients with gingivitis. Details: A small clinical study in adults with mild or moderate plaque-induced gingivitis shows that applying half a teaspoon of gum arabic powder to the buccal surface of dentogingivial areas for 5 minutes then rinsing with tap water twice daily for 60 days reduces gingival inflammation in patients with mild, but not moderate, gingivitis when compared with placebo (111508). Another small clinical study in patients with chronic gingivitis shows that applying a pea-size amount of gel containing a mixture of ingredients including gum arabic, barleria, medlar, terminalia, and melia (Gum Tone Gel, Charak Pharma Pvt Ltd.) after brushing for 6 weeks decreases gingivitis severity when compared with placebo. The gel was no better than using chlorhexidine 1% gel (92887). However, it's unclear if these findings are due to gum arabic, other ingredients, or the combination.
• Hypercholesterolemia. It is unclear if oral gum arabic helps to reduce high cholesterol levels. Details: One small clinical study in patients with hypercholesterolemia shows that taking gum arabic 5 grams twice daily for 4 weeks does not seem to affect plasma lipid levels when compared with baseline (8072).
• Irritable bowel syndrome (IBS). Although there is interest in using oral gum arabic for IBS, there is insufficient reliable information about the clinical effects of gum arabic for this condition.
• Kidney failure. Although there is interest in using oral gum arabic for kidney failure, there is insufficient reliable information about the clinical effects of gum arabic for this condition.
• Metabolic syndrome. It is unclear if oral gum arabic is beneficial for preventing metabolic syndrome. Details: One small clinical study in healthy adults at risk for metabolic syndrome shows that taking gum arabic 20 grams daily for 12 weeks modestly reduces blood pressure and increases fat-free mass when compared with baseline, but not when compared with taking pectin 1 gram. There were no changes in weight, glycated hemoglobin, or cholesterol levels (105039).
• Obesity. It is unclear if oral gum arabic is beneficial for promoting weight loss. Details: One small clinical study in healthy adults shows that taking powdered gum arabic 18 grams in the morning and 12 grams in the evening for 6 weeks reduces body mass index by 0.32 kg/m2 and body fat percentage by about 2% when compared with placebo. Body weight was also reduced by 1.2%, but this was not significant when compared with placebo (18237). It is unclear if gum arabic is beneficial in individuals with obesity.
• Peristomal lesions. It is unclear if topical gum arabic is beneficial for preventing peristomal lesions in patients with a colostomy bag. Details: Preliminary clinical research in infants shows that applying a thick layer of gum arabic gel to peristomal skin before attaching a colostomy bag twice daily for 4 weeks decreases the incidence of postoperative peristomal dermatitis by about 78% when compared with zinc sulfate ointment (92886).
• Sickle cell disease. It is unclear if oral gum arabic is beneficial in patients with sickle cell disease. Details: Preliminary clinical research in patients with sickle cell disease shows that taking gum arabic powder 30 grams daily for 12 weeks does not improve most markers of liver and kidney function in these patients. While an improvement in direct bilirubin levels was observed when compared to baseline, no significant changes in serum levels of total bilirubin, albumin, protein, liver enzymes, urea, or creatinine were reported (102087). However, in this same group of patients, gum arabic did reduce levels of total cholesterol by 8 mg/dL, low-density lipoprotein (LDL) cholesterol by 5 mg/dL, and triglycerides by 12 mg/dL when compared with baseline. Significant improvements in high-density lipoprotein (HDL) cholesterol were lacking (102088). This research is limited by the lack of a control group, Also, it is unclear whether gum arabic can improve clinical outcomes in patients with sickle cell disease. More evidence is needed to rate the effectiveness of gum arabic for these uses.

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LIKELY INEFFECTIVE

• Alzheimer disease. Lecithin does not improve daily functioning in patients with Alzheimer disease. Details: In patients with Alzheimer disease, taking various types of lecithin, 1.2-45 grams daily for up to 6 months, alone or in combination with various conventional medications, does not improve cognitive function or other measures of disease progression (5149,5151,5152,5156,14817,14823,14825,14837,14838).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Age-related cognitive decline. It is unclear if oral lecithin can slow age-related cognitive decline. Details: A small clinical crossover study in healthy adults aged 64 years and older shows that taking lecithin 26 grams orally daily, alone or in combination with physostigmine, for 5 weeks does not seem to improve memory when compared with placebo (19204).
• Anxiety. Although there is interest in using oral lecithin for anxiety, there is insufficient reliable information about the clinical effects of lecithin for this condition.
• Atopic dermatitis (eczema). Although there is interest in using oral lecithin for atopic dermatitis, there is insufficient reliable information about the clinical effects of lecithin for this condition.
• Bipolar disorder. It is unclear if oral lecithin is beneficial in patients with bipolar disorder. Details: A clinical study in six patients with mania shows that taking lecithin 10 mg three times daily improves symptoms of delusions, incoherent speech, and hallucinations when compared with placebo (14839).
• Dry skin. Although there is interest in using topical lecithin for dry skin, there is insufficient reliable information about the clinical effects of lecithin for this condition.
• Friedreich ataxia. Small clinical studies suggest that oral lecithin is not beneficial in people with Friedreich ataxia. Details: Preliminary clinical research shows that taking lecithin 25 grams orally daily for 1 month does not have any benefit in people with Friedreich ataxia (59298). Other preliminary clinical research shows that taking lecithin for a longer period of 6 months also does not improve performance (19211).
• Hyperlipidemia. Although lecithin may lower cholesterol in healthy people, it does not seem to improve cholesterol levels in people with hyperlipidemia. Details: Some clinical research shows that taking lecithin 20-30 grams daily for up to 11 months decreases cholesterol in healthy people (5147,14820). However, other clinical research shows that lecithin has no effect on low-density lipoprotein cholesterol or total cholesterol levels in people with hyperlipidemia (5148,14820).
• Parkinson disease. It is unclear if oral lecithin is beneficial in patients with Parkinson disease. Details: Preliminary clinical research in patients with Parkinson disease shows that taking lecithin 32 grams daily for 8 weeks does not improve symptoms when compared with placebo (19212).
• Postoperative pain. It is unclear if oral lecithin is beneficial for reducing postoperative pain. Details: Preliminary clinical research shows that taking lecithin 20 grams prior to surgery increases choline levels, but does not reduce postoperative pain after gynecological surgery, when compared with placebo (91231).
• Tardive dyskinesia. It is unclear if oral lecithin is beneficial in patients with tardive dyskinesia. Details: Two small clinical studies in patients with tardive dyskinesia shows that taking lecithin orally for 2 months, alone or in combination with lithium, does not improve symptoms when compared with placebo (14822,14824).
• TPN-associated hepatic steatosis. It is unclear if oral lecithin is beneficial in patients with hepatic steatosis associated with long-term total parenteral nutrition (TPN). Details: A small clinical study in patients on long-term TPN with low choline levels suggests that taking lecithin 20 grams orally twice daily for 6 weeks reduces the degree of hepatic steatosis, compared with no significant changes in those taking placebo (5140).
• Ulcerative colitis. Oral lecithin has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that taking a disease-specific medical food (Profermin, Nordisk Rebalance) containing lecithin, fermented oats, barley malt, and lactobacillus plantarum, as 250 mL twice daily for 24 weeks, decreases disease activity by over 56% when compared with baseline and leads to remission in 46% of patients with mild-to-moderate ulcerative colitis (91228). Other preliminary clinical research in this population shows that taking Profermin 250 mL twice daily for 8 weeks improves disease activity and remission rate when compared with another medical food (Fresubin Original, Fresenius Kabi) (90271). The effects of lecithin alone are unclear. More evidence is needed to rate lecithin for these uses.

(Read more about LECITHIN)

POSSIBLY EFFECTIVE

• Breast cancer. High dietary intake of soy might be beneficial for the prevention of breast cancer and breast cancer recurrence in some patients. However, soy supplements do not seem to be beneficial. Details: For prevention, most population research has found that higher dietary intake of soy is associated with up to a 26% reduced odds of developing breast cancer when compared with a lower intake (7335,7336,11038,11807,75377,75587,90955,108251). One meta-analysis of population research found that patients who consumed more than 15 mg soy isoflavones daily made up about 25% of all cases of breast cancer, compared with 75% of cases in the group of patients consuming less than 15 mg daily (108251). The effects appear to vary depending on the ethnicity of the patient. Population research has consistently found that a high-soy diet in Asian and Asian-American females is associated with a significantly reduced risk of breast cancer (7335,7336,11038,11807,75377,75587,90955). However, the amount of soy consumed in a Western diet, even among those who consume the highest amounts of soy, was not found to have a preventative effect (11391,17109,90955,90967). The reason for the disparate findings are unknown but may be related to genetic differences or differences in quantification of soy intake (7663,94153). Also, the prophylactic benefit seems to apply regardless of whether high amounts of soy are consumed during adolescence or later in life (7335,7336,9674). Limited population research has also found that consuming a diet high in soy is associated with up to a 25% reduced risk of breast cancer recurrence; however, it is unclear whether there is an association with reduced mortality in breast cancer patients (90956,90969,94154). The effect appears to be greater for certain subgroups of breast cancer patients. Increased dietary soy intake is associated with a 28% to 36% risk reduction in patients with estrogen receptor (ER)-negative tumors, a 30% risk reduction in patients with ER-positive/progesterone receptor (PR)-positive tumors, and a 25% to 36% risk reduction in postmenopausal patients (90956). Some small clinical studies have also evaluated the use of soy isoflavone extract . One small clinical study in patients with breast cancer shows that taking a soy isoflavone extract 200 mg daily for 2 weeks prior to surgery does not seem to affect cancer cell growth when compared with a historical control (11042). Another small clinical study in patients at high risk for breast cancer or with a history of breast cancer shows that taking a soy tablet containing 50 mg soy isoflavones (Novasoy, Archer Daniels Midland Co.) daily for 12 months does not alter mammographic or breast tissue density when compared with placebo (95999).
• Chronic kidney disease (CKD). Oral soy protein seems to improve some measures of disease severity in patients with CKD. Details: Clinical research shows that consuming soy protein seems to reduce proteinuria in people with kidney disease (2286,2287,2288,75249,75634). Also, a meta-analysis of clinical research in patients with CKD who are not on dialysis shows that soy protein intake reduces serum levels of creatinine by 0.07 mg/dL, phosphorus by 2.5 mg/dL, and triglyceride by 18 mg/dL when compared with placebo or control (90989).
• Diabetes. Diets high in soy seem to reduce the risk of type 2 diabetes. Also, oral soy protein, but not soy isoflavones, seems to modestly improve glycemic indices. It is unclear if soy is beneficial for lowering blood lipid levels or reducing cardiovascular (CVD) mortality risk in adults with type 2 diabetes. Details: A meta-analysis of observational studies has found that higher dietary intake of tofu, soy protein, or soy isoflavones is associated with an 8% to 16% lower risk of developing diabetes when compared with a lower dietary intake (105608). In menopausal patients without diabetes, a meta-analysis of clinical research shows that intake of soy isoflavones 40-161 mg daily seems to improve glycemic indices when compared with control (96423). Some research shows that soy can modestly improve glycemic indices in patients with diabetes. A meta-analysis of small low-quality clinical studies in patients with diabetes or metabolic syndrome shows that taking various formulations of soy protein modestly reduces fasting plasma glucose and insulin levels, as well as insulin resistance, when compared with control (96001). An older meta-analysis assessing both healthy patients and patients with diabetes shows that a whole soy diet reduces fasting blood glucose by about 4 mg/dL when compared with control (75493). Small clinical studies also suggest that an extract of the fermented soybean product, Touchi, acts as an alpha-glucosidase inhibitor. It seems to modestly lower blood glucose, glycated hemoglobin (HbA1c), and triglycerides in patients with type 2 diabetes (11762,75205). However, some conflicting evidence exists. A meta-analysis of small, low-quality clinical studies in patients with type 2 diabetes shows that taking soy isoflavones does not improve glycemic indices when compared with control (105610). Also, another meta-analysis of clinical research in patients with type 2 diabetes shows that taking soy protein and/or soy isoflavones for 6-12 weeks does not improve glycemic indices when compared with either soy protein without isoflavones, other protein, or placebo (105610). Reasons for these conflicting results are unclear but may relate to differences in baseline blood glucose levels, the formulation of soy, or the duration of treatment. Some research shows that soy may modestly improve the lipid profile in patients with diabetes. A meta-analysis of clinical research in patients with diabetes shows that taking soy protein and/or soy isoflavones for 6-12 weeks modestly reduces levels of total and low-density lipoprotein (LDL) cholesterol, but not high-density lipoprotein (HDL) cholesterol or triglycerides, when compared with control (105610). Consuming soy foods might reduce the risk of mortality related to CVD in patients with diabetes. Population research suggests that consuming soy foods at least four days each week is associated with a 23% reduced risk of CVD mortality when compared with never consuming soy foods. Consuming soy foods less than four times weekly is not associated with CVD mortality risk (108242). Soy is also of interest in the prevention or treatment of gestational diabetes. Population research has found that consumption of less than 40 grams of soy daily in the second trimester is associated with a 2.1-fold increased risk of gestational diabetes when compared with daily soy intake of 40 grams or more (108241). Also, a small clinical trial in patients with gestational diabetes shows that consuming a diet containing about 0.3 grams/kg soy protein for 6 weeks, beginning at 24-28 weeks' gestation, reduces blood glucose levels, insulin resistance, and triglyceride levels when compared with consuming a non-soy control diet (95993).
• Diarrhea. Oral soy fiber seems to reduce acute diarrhea in infants, although it may not be beneficial in adults. Details: Giving soy fiber-supplemented formula orally, either alone or in combination with oral rehydration solution, seems to reduce the duration of acute diarrhea in infants when compared with cow's milk formula or oral rehydration solution alone (2291,2292,75474,75517,75523,75531,75572). However, in some studies, a reduction in the duration of acute diarrhea was not observed when compared with cow's milk formula (75522,75542). In adult patients receiving nutrition via intubation, preliminary clinical research suggests that treatment with soy-polysaccharide fiber does not improve the incidence of diarrhea when compared to control (75508).
• Galactosemia. Oral soy protein can be used in infant formula to prevent symptoms of galactosemia. Details: Soy does not contain the sugar galactose. Some research suggests that giving oral isolated soy protein-based formula in place of milk-based formula to infants seems to be helpful for preventing symptoms of galactosemia (3400).
• Hyperlipidemia. Oral soy protein seems to modestly reduce lipid levels. However, purified soy isoflavone may not have the same benefit. Details: Consuming soy protein orally, in place of other dietary protein, seems to modestly reduce total cholesterol and low-density lipoprotein (LDL) cholesterol by about 3% to 4% when compared with control (842,2293,2294,2296,2585,3402,4755,6412,7346,7803)(8530,10459,42059,75356,105598,105604). Additionally, some research shows that soy protein might be more effective in patients with more severe hyperlipidemia (75497). The FDA has approved labeling for specific soy products that states that they may be used for cholesterol reduction in combination with a diet low in saturated fat and cholesterol. To be eligible for this labeling, soy products must provide at least 6.25 grams of soy protein per serving, which is 25% of the effective daily intake (3977). However, not all evidence is positive. Some studies have shown no benefit of soy protein or isoflavones on LDL cholesterol levels when compared to control (8521,9679,12034,17105,53771,75236)(75242,75274,75276). Furthermore, although a few clinical trials have shown significant decreases in triglycerides following supplementation with soy or soy protein isolate (75258,75365), most studies suggest that soy protein does not decrease triglycerides when compared to control (2293,6412,8530,12034,17105). The effect of soy protein on high-density lipoprotein (HDL) cholesterol is inconsistent. Most studies suggest that it does not increase HDL levels (2293,6412,8530,12034,75286)(75524), although some analyses of clinical research suggest that soy might increase HDL cholesterol levels by up to 4% when compared to control (75480,75497). Doses of soy protein have ranged from 25-135 grams daily, providing 40-318 mg daily of isoflavones; however, higher doses do not seem to be more effective (17106,105598). Some evidence suggests that soy protein providing more isoflavones, or supplemented with isoflavones, might be more effective (3402,6413,10459), but this has not been consistently found in studies (3402). Most studies evaluating soy protein products containing little to no isoflavones suggest that these products are not effective (3402,7346,9679); however, purified soy isoflavone supplements alone do not seem to decrease LDL cholesterol (851,4738,7345,8502,10459,14066). In addition to soy protein, limited evidence suggests that soy fiber alone might reduce total cholesterol, LDL cholesterol, and triglyceride levels when compared with placebo (75686,75689). There is also some evidence that ultra-high temperature (UHT) treatment of soy milk destroys any cholesterol-lowering activity (17106).
• Hypertension. Oral soy seems to modestly reduce blood pressure in some patients. Details: A meta-analysis of the available clinical research shows that consuming soy products modestly lowers systolic and diastolic blood pressure by an average of 1.6 mmHg and 1.2 mmHg, respectively, when compared with control (105605). This analysis is limited by high risk of bias and the lack of a dose-response relationship. An older meta-analysis, as well as individual clinical studies, in patients with prehypertension or mild hypertension show that consuming soy protein 18-40 grams, providing 118-143 mg of isoflavones, daily or black soy peptide 4.5 grams daily for 8 weeks reduces systolic blood pressure by about 4-8 mmHg and diastolic blood pressure by about 3-5 mmHg when compared with control (1313990962,90965). In normotensive patients, soy protein does not seem to reduce systolic or diastolic blood pressure (90965).
• Lactose intolerance. Oral soy protein can be used in infant formula to prevent symptoms of lactose intolerance. Details: Providing isolated soy protein-based formula orally to infants is an acceptable alternative to milk-based formulas, especially for infants with symptoms of lactose intolerance (3400).
• Menopausal symptoms. Oral soy seems to reduce hot flashes in patients with menopausal symptoms. Details: Consuming soy protein 15-60 grams, providing 34-100 mg of isoflavones, daily seems to modestly decrease the frequency and severity of hot flashes in some menopausal adults. Improvement seems to be greater in those with a higher frequency of hot flashes at baseline (2296,2297,3978,3986,3987,7653,9917,11805,15220,17110,75478)(75486,75649,92661,95997). Taking concentrated soy isoflavone extracts, providing 35-200 mg of isoflavones, daily seems to have similar effects (4751,6455,7802,9916,10460,11805,11993,11994,13209,15220)(15850,75478,90950,90979,92661). Higher doses of 100-200 mg of isoflavones daily and higher frequency of dosing intervals seem to have greater benefit (90950). Furthermore, the amount of the specific isoflavone genistein contained in a soy product may influence outcomes. According to one analysis, studies using products that provide at least 15 mg of genistein daily consistently show positive outcomes. Studies using products containing a lower concentration of genistein have produced inconsistent findings (15133). Not all research has found that soy extracts reduce hot flashes (7801,11806,14062,15038,15851,16762); some experts speculate that this is due to a high placebo response (9916). Some clinical research has compared soy isoflavone extracts to conventional estrogen replacement. In one study, a concentrated soy isoflavone extract of genistein 54 mg daily reduced hot flashes by 22% to 29%, compared to 54% in those taking 17beta-estradiol as 1 mg daily plus norethisterone acetate 0.5 mg daily (11994). Additional preliminary research suggests that taking a soy isoflavone extract providing 60 mg isoflavones twice daily is comparable in efficacy to conjugated estrogens 0.625 daily for reducing menopausal symptoms. Conjugated estrogens seem to work more quickly; it seems to take up to 2 months to achieve the full effect of soy isoflavones (13209). One clinical trial compared soy isoflavones 10-40 mg daily to S-equol, a soy isoflavone metabolite. Soy isoflavones were less effective for reducing hot flash frequency when compared with S-equol (90960). This has led to some speculation that the effectiveness of soy in relieving hot flashes is influenced by a patient's ability to convert daidzen, a soy isoflavone, to S-equol (90950). It is theorized that patients who are S-equol producers are more likely to achieve symptom relief from soy. However, observational and clinical research does not support this theory (90990,94162). Soy has also been evaluated for the management of other symptoms of menopause. Some clinical research in menopausal patients with depression suggests that taking soy 100 mg, providing 50 mg of soy isoflavones, in combination with sertraline 50 mg daily for three months improves depression severity when compared with sertraline or soy alone (90958). An analysis of two small clinical trials shows that supplemental soy providing 50-118 mg of isoflavones can reduce vaginal dryness scores by 0.26 when compared with control (92661). Also, an open-label study suggests that drinking a specific beverage (ViveSoy) containing soy protein 15 grams and soy isoflavones 50 mg orally daily for 12 weeks reduces overall urogenital symptoms when compared with a control group (95997). However, one small clinical study in perimenopausal patients shows that a soy-rich diet does not relieve urogenital symptoms, including vaginal dryness, itching, and urinary incontinence, when compared with a soy-free diet (75285).
• Metabolic syndrome. Oral soy protein seems to improve glycemic control and other markers of metabolic syndrome. Details: A meta-analysis of clinical research in patients with diabetes or metabolic syndrome shows that following a diet high in soy protein can decrease fasting plasma glucose and insulin levels, as well as insulin resistance, when compared with a control diet. Furthermore, dietary intake of soy protein modestly decreases diastolic blood pressure and low-density lipoprotein (LDL) cholesterol by a small amount in this population, although there is no effect on systolic blood pressure, high-density lipoprotein (HDL) cholesterol, or triglycerides (96001). Other clinical research shows that consuming a soy nut diet or a soy protein diet reduces fasting plasma glucose and LDL cholesterol levels when compared to baseline in postmenopausal adults with metabolic syndrome; however, the soy nut diet seems to more beneficial than either the soy protein diet or a Dietary Approaches to Stop Hypertension (DASH) diet (75378).
• Muscle strength. Oral soy protein seems to increase muscle strength. Details: Overall, soy protein combined with resistance training seems to increase muscle strength when compared with placebo (16748,75246,96942,98871). A meta-analysis of three clinical studies shows that consuming soy protein in addition to resistance training improves strength and lean body mass in untrained athletes (98871). Other clinical research shows that soy also improves muscle strength in trained athletes and postmenopausal adults (75246,96942). One study in Olympic endurance athletes shows that consuming isolated soy protein (Supro) 1.5 grams/kg daily for 8 weeks increases body mass and strength indices and reduces fatigue when compared with no protein supplementation (75246). Clinical research in postmenopausal adults undergoing resistance training 3 days weekly shows that taking soy protein 25 grams daily in skim milk for 16 weeks increases the maximum amount of weight lifted in one repetition by over 80% for both bench press and knee extension when compared to a maltodextrin placebo (96942). Soy protein has also been compared with other protein supplements. A meta-analysis of preliminary clinical studies and other clinical research show that soy protein seems to work as well as whey, beef, and dairy (casein and whey) protein for improving muscle strength (75404,85941,98871,105591). However, the validity of these findings is limited by the small size and high heterogeneity of the studies.
• Osteoporosis. Oral soy isoflavones seem to improve bone density and reduce the risk of osteoporosis in post-menopausal adults. Details: Most clinical research suggests that soy protein or soy extract containing 75-90 mg of isoflavones can increase bone mineral density (BMD), or slow BMD loss, and improve biochemical markers of bone turnover in peri- and postmenopausal adults when compared with control (842,4951,6449,9775,11082,90972,90980). Lower doses of isoflavones do not seem to be as beneficial. However, some observational research in postmenopausal Japanese adults and Chinese females aged 30-40 years has found that consuming about 50 mg dietary soy isoflavones daily is associated with a higher BMD when compared with lower soy isoflavone intake (7342,11081). An observational study in postmenopausal Asian patients has found that consuming higher dietary soy protein is associated with a lower risk of developing fractures when compared with lower amounts (13181). However, not all research has been positive. Some conflicting evidence suggests that soy protein does not improve BMD in some postmenopausal adults. The discrepancy in findings may be due to differences in soy formulations, concomitant treatments, or variable patient populations (4952,12034,14064,90978). For example, most evidence shows that soy does not affect BMD in premenopausal patients or bone turnover in adolescents (7660,8532,9684,11086). It is theorized that only people who can convert daidzein, a soy isoflavone, to S-equol might obtain benefits from soy (4952). However, clinical research suggests that there is no difference in bone calcium retention between equol producers and nonproducers (95995).

POSSIBLY INEFFECTIVE

• Benign prostatic hyperplasia (BPH). Oral soy does not seem to reduce BPH symptoms. Details: Clinical research in patients with BPH shows that taking soy isoflavones 40 mg (Soylife 40, Acatris) daily for 12 months does not improve peak urine flow rate, residual urine volume, symptoms of BPH, or general quality of life when compared with placebo (90983).
• Breast cancer-related hot flashes. Oral soy does not seem to reduce the risk for breast cancer-related hot flashes. Details: Clinical research shows that consuming a soy beverage providing soy isoflavones 90 mg daily or taking a soy extract providing soy isoflavones 50 mg three times daily does not reduce hot flashes in breast cancer survivors (3991,7658,8499). Observational research in breast cancer survivors has also found no association between hot flash incidence and soy isoflavone consumption (105602).
• Colorectal cancer. Oral soy does not seem to reduce the risk for colorectal cancer. Details: Some observational research from China and Japan has found that intake of soy protein or soy isoflavone is not associated with the risk of developing colorectal cancer (105601). Furthermore, some clinical research shows that soy protein powder 58 grams containing isoflavones 83 mg, taken daily for 12 months, does not reduce the proliferation of colorectal epithelial cells in patients with adenomatous polyps when compared to control (75282).
• Exercise-induced muscle soreness. Oral soy does not seem to reduce muscle soreness after exercise. Details: Some clinical research shows that taking soy isoflavone extract 120 mg orally for 30 days prior to exercise doesn't ameliorate muscle soreness caused by exercise when compared with placebo (8524).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Alzheimer disease. It is unclear if oral soy improves cognition in patients with Alzheimer disease. Details: Preliminary clinical research in patients with Alzheimer disease shows that taking soy isoflavones (Novasoy, Archer Daniels Midland Co.) 100 mg daily for 6 months does not improve cognition when compared with placebo (96424).
• Androgen deprivation therapy (ADT)-associated hot flashes. One small clinical study in patients with prostate cancer receiving ADT shows that taking soy protein powder 20 grams, providing 160 mg of isoflavones, alone or along with venlafaxine 75 mg, once daily for 12 weeks does not improve the severity of hot flash symptoms when compared with milk protein, with or without venlafaxine (90981).
• Asthma. It is unclear if oral soy reduces asthma symptoms. Details: One population study has found that people with asthma who consume soy foods providing more than 250 mcg of genistein for every 1000 kcal consumed (e.g., 500 mcg/day for 2000 kcal diet) daily have increased lung function, as measured by FEV1 scores, when compared to those who consume less (11084). However, clinical research in adult and pediatric patients with poorly controlled asthma shows that taking soy isoflavones 50 mg twice daily for 24 weeks does not improve FEV1 scores, reduce the number of asthma episodes, or improve asthma symptoms when compared with placebo (90977).
• Cardiovascular disease (CVD). It is unclear if soy consumption reduces the risk for CVD or CVD-related mortality. More research is needed to determine whether certain populations may benefit from increased soy intake. Details: Due to mixed findings, it is unclear if consuming soy is associated with a reduced risk of CVD events. One population study has found that consuming at least 60 grams of soy daily over a 12-month period is associated with a 14% reduced risk of having a CVD event over the next 5 years, as well as a reduced risk of stroke, when compared with consuming less than 15 grams daily (108253). A study in Japan has found that consuming soy five or more times per week over a 10-year period is associated with fewer adverse cardiovascular outcomes in only a certain subset of patients when compared with consuming soy twice a week or less. Postmenopausal adults with the highest consumption had a 36% lower risk of stroke, a 45% lower risk of myocardial infarction, and a 65% lower risk of CVD mortality. However, risk was not significantly reduced in males or premenopausal adults (17108). In contrast, a study in Korea has found that consuming a median of 16.5 servings of soy per week is associated with a 64% reduced risk of CVD incidence in premenopausal, but not postmenopausal, adults when compared with a median of 4.7 servings per week. A subgroup analysis has found that the highest intake of tofu, but not soybeans, fermented soy paste, or soy milk, is associated with a reduced incidence of CVD (108243). Additionally, higher dietary intake of soy does not seem to be associated with a reduced risk of cardiovascular events in Western females (13040). The amount of phytoestrogens typically consumed in Western diets is significantly lower than the amount typically consumed in Asian diets. The form of soy food and isoflavone content might play a role in these discrepancies. Any association between consumption of soy-containing foods and CVD mortality is also unclear. A meta-analysis of observational studies conducted in China or Japan has found that the highest intake of soy-containing foods is not associated with a lower risk of CVD-related mortality when compared with the lowest intake (96941). A population study in patients with or without a prior history of CVD has also found that soy-containing food consumption is not associated with a lower risk of CVD-related mortality when compared with the lowest intake (108244). However, some research has found a positive effect of soy consumption on CVD mortality risk. A subgroup analysis of a meta-analysis has found that the highest intake of fermented soy products is associated with a 16% reduced risk of CVD mortality; higher intake of non-fermented soy is not associated with CVD mortality (96941). Population research in patients without a prior history of CVD has found that soy-containing food consumption is associated with a lower risk of myocardial infarction-related mortality when compared with the lowest intake (108244). Also, one population study in adults with type 2 diabetes has found that consuming soy-containing foods at least four days each week is associated with a 23% reduced risk of CVD mortality when compared with never consuming soy foods. Consuming soy foods less than four times weekly is not associated with CVD-related mortality (108242).
• Cervical cancer. It is unclear if oral soy reduces the risk for cervical cancer. Details: Population research has found that the highest dietary intake of soy over approximately 17 years is associated with a 57% decreased risk of cervical cancer when compared to the lowest intake of soy in females who also drank green tea. However, neither soy intake nor green tea intake alone was associated with a decreased risk of cervical cancer. Additionally, other population research has not confirmed an association between soy intake and cervical cancer (101800).
• Child growth. It is unclear if oral soy protein enhances child growth. Details: Preliminary clinical research in Colombian children 2-7 years of age shows that consuming a soy protein supplement dissolved in fruit juice on 6 days of every week for 1 year does not improve body mass index, body composition, weight, or height when compared with consuming fruit juice and whole milk. A sub-analysis shows that children consuming the soy protein supplement had an increase in weight-for-age when compared with the control group, indicating that the supplement may be beneficial for ensuring adequate weight and nutritional status during prepubertal growth (100320). However, the children in this study had normal or below average weight-for-age at baseline, limiting the applicability of these findings to other patient populations.
• Cognitive function. It is unclear if oral soy improves cognitive function; research is conflicting. Details: Some research shows that college students who increase consumption of soy foods providing isoflavones 100 mg daily have improved short- and long-term memory (9671). Postmenopausal patients aged 50-65 years who take a soy extract supplement providing isoflavones 60 mg daily also seem to have some improvement in some measures of cognitive function (12048). There is also evidence in postmenopausal patients aged 55-75 years that taking a soy extract supplement providing isoflavones 110 mg daily might improve verbal memory scores (12040). However, another study in this population shows that consuming 25.6 grams daily of soy protein providing 99 mg of isoflavones does not improve cognitive function (12034). Similarly, population research in females aged 42-52 years has found that increasing dietary intake of the isoflavones genistein and daidzein is not associated with improved measures of cognitive function (15042). These differing findings might be explained by variations in study design and soy formulations.
• Cognitive impairment. Oral soy has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research in adults 55 years of age and older with mild cognitive impairment shows that taking a specific combination product (DW2009) containing fermented soybean powder and Lactobacillus plantarum daily for 12 weeks modestly improves composite cognitive function when compared with placebo (100319). It is not clear if this effect is due to soy, lactobacillus, or the combination.
• Colic. It is unclear if oral soy is beneficial in infants with colic. Details: Preliminary clinical research shows that consuming soy-based formula might reduce the duration of colic symptoms in infants with cows' milk intolerance (75509,75543). However, other clinical research shows that consuming soy-based formula does not improve crying in infants with colic when compared with dicyclomine hydrochloride 3 mg/kg daily (75573). Also, a meta-analysis of only high quality clinical research shows that soy milk formula does not improve the persistence of colic or the duration of crying in infants with colic when compared with control (75611).
• Crohn disease. It is unclear if oral soy improves symptoms of Crohn disease. Details: A small observational study in patients with inactive Crohn disease has found that taking oral soy-derived protein in combination with enteral treatment for 4 weeks is associated with increased bowel movements, improved symptoms such as fatigue and mental strain, and increased body weight when compared with standard enteral treatment alone (75175).
• Diabetic nephropathy. It is unclear if oral soy improves kidney function in patients with diabetic nephropathy. Details: A meta-analysis of small clinical trials in patients with diabetic nephropathy shows that consuming soy products, such as soy protein and soy milk, modestly reduces proteinuria and blood urea nitrogen (BUN), as well as levels of total and low-density lipoprotein (LDL) cholesterol, triglycerides, and fasting blood glucose, when compared with animal protein or cow's milk. However, there was no effect on any measures of kidney function (108247). Some individual small clinical trials show that replacing dietary animal protein with soy protein reduces urinary albumin excretion in patients with diabetic nephropathy (7348,12555,12556). However, one small clinical study shows that consuming soy milk 240 mL daily for 4 weeks does not affect urinary creatinine, blood urea nitrogen, proteinuria, or glomerular filtration rate in patients with diabetic nephropathy (90966).
• Dyspepsia. Oral soy protein has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in adults with mild or moderate dyspepsia shows that consuming 1 gram of toasted soy flour fermented with Lactobacillus delbrueckii up to three times daily for 3 weeks does not improve heartburn severity or frequency when compared with placebo (105599).
• Endometrial cancer. It is unclear if oral soy protein reduces the risk for endometrial cancer. Details: Most epidemiological research has found that increased soy intake is associated with a lower risk of endometrial cancer. Endometrial cancer incidence is lower in Japan, China, and other Asian countries where the typical diet is low in calories and high in soy, whole grain foods, vegetables, and fruits (7338,11036,90954). Also, a large meta-analysis of population research has found that the highest total and fermented soy intake is associated with a 17% to 19% reduced risk of developing endometrial cancer when compared to the lowest intakes in postmenopausal adults (96002). However, one clinical study shows that taking soy protein 25 grams daily providing 91 mg of aglycon equivalents of isoflavones and glycosides for three years does not reduce the risk of endometrial hyperplasia or cancer when compared with placebo in postmenopausal adults. However, this study may not have been adequately powered to detect small differences in the low rates of endometrial hyperplasia (90971).
• Fibromyalgia. It is unclear if oral soy reduces fibromyalgia symptoms. Details: Clinical research shows that consuming a shake containing soy protein 20 grams and soy isoflavone 160 mg once daily for 6 weeks does not improve physical functioning or symptoms of depression in patients with fibromyalgia when compared with placebo (75451).
• Gastric cancer. It is unclear if oral soy reduces the risk for gastric cancer. Details: Meta-analyses of population research have found that the highest intake of soy-containing foods and nonfermented soy products is associated with a 21% to 37% decreased risk of gastric cancer when compared with the lowest intake (95998,108246). Intake of at least 100 grams daily of nonfermented soy foods was found to be the most protective (95998). However, a high intake of fermented soy products is associated with an increased risk of gastric cancer, and intake of 1-5 cups daily of the fermented soy product miso soup is associated with an increased risk of gastric cancer in males (95998,108246).
• Hepatitis C. It is unclear if oral soy is beneficial for hepatitis C. Details: Preliminary clinical research in patients with hepatitis C shows that taking soy protein 32 grams daily for 12 weeks reduces the number of cases of steatosis by 47% and reduces alanine aminotransferase (ALT) levels by 13% when compared to baseline. However, it is no different than taking casein protein (90970).
• Irritable bowel syndrome (IBS). A small study suggests that oral soy isoflavones might reduce IBS symptoms. Details: A small clinical study in females with IBS shows that taking soy isoflavones 40 mg daily for 6 weeks improves symptoms of IBS, such as abdominal distention and abdominal pain severity and duration, by approximately 27% when compared with placebo. Quality of life is also improved. Some symptoms are also improved when soy isoflavones are taken in combination with vitamin D; however, the combination of soy isoflavones and vitamin D does not seem to improve symptoms better than soy isoflavones alone (96425).
• Lung cancer. It is unclear if dietary soy reduces the risk for lung cancer. Details: A meta-analysis of epidemiological research has found that although increased soy intake is not associated with a reduced risk of lung cancer overall, it is associated with a slightly reduced risk in nonsmoking adults (90985).
• Mastalgia. It is unclear if oral soy is beneficial for mastalgia. Details: A small clinical study suggests that soy milk providing 34 grams soy protein daily might reduce cyclical breast pain when compared with no intervention (2428).
• Migraine headache. Oral soy has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Clinical research shows that taking a combination of soy isoflavones 60 mg, dong quai 100 mg, and black cohosh 50 mg daily for 24 weeks reduces the frequency of menstrual-associated migraine attacks when compared with placebo (35797). It is not clear if this effect is due to soy, the other ingredients, or the combination.
• Neonatal jaundice. It is unclear if oral soy reduces the risk of neonatal jaundice. Details: Clinical research shows that patients with gestational diabetes who consume a diet containing soy protein along with other plant and animal proteins for 6 weeks beginning at 24-28 weeks' gestation have a 73% reduced risk for newborn hyperbilirubinemia when compared with those consuming a control diet containing only non-soy plant and animal proteins (95993).
• Nonalcoholic fatty liver disease (NAFLD). It is unclear if oral soy is beneficial for the treatment or prevention of NAFLD. Details: Observational research in a Chinese population has found that increased frequency of dietary soy consumption is associated with a lower incidence of NAFLD when compared with lower consumption (105612). A meta-analysis of three small clinical trials in patients living in Iran with NAFLD shows that consuming soy milk, soy foods, or a genistein supplement for 8 weeks might reduce some liver transaminase levels when compared with control (105611). Another meta-analysis of small clinical trials in patients with NAFLD shows that consuming soy milk, soy foods, or a genistein supplement for 8 or 24 weeks modestly improves insulin resistance but does not improve body mass index, cholesterol levels, or liver transaminase levels (108239). These analyses are limited by their generally small population size and the heterogeneity of interventions.
• Obesity. It is unclear if consuming oral soy protein as part of a calorie-restricted diet improves weight loss; research is conflicting. Details: Some clinical research shows that consuming soy protein in conjunction with calorie restriction for 2-6 months helps reduce weight in those who are obese and overweight when compared with calorie restriction alone (11085,75397). Other clinical research shows that consuming soy protein for 16 weeks improves weight loss in overweight females when compared with consuming protein from meat (75620). Also, consuming black soy peptide 4.5 grams daily for 12 weeks reduces body weight and body fat mass more than placebo in overweight and obese adults (90961). In addition, some clinical evidence shows that eating biscuits supplemented with soy fiber 100 grams daily for 12 weeks reduces body weight, body mass index (BMI), and low-density lipoprotein (LDL) cholesterol when compared to control in overweight and obese patients (90960). However, contradictory evidence exists. Some clinical research shows that following a calorie-restricted diet and consuming soy-based meal replacements 3-5 times daily for 12-16 weeks, or eating soy protein-rich foods in place of animal protein for 2-12 weeks, does not improve weight loss in overweight or obese individuals when compared to a calorie-restricted diet alone (75277,75372,75376,90968). Also, in overweight and obese females following a free-choice diet, soy protein 56 grams daily for 23 weeks does not appear to improve weight loss when compared to eating an isoenergetic amount of carbohydrates (86077). Finally, a subgroup analysis of six preliminary clinical trials shows that soy products do not improve weight loss in postmenopausal adults (98870). The reason for these disparate findings is unclear but may be due to differences in the soy products used or differences in patient population. For example, a meta-analysis of clinical research shows that phytoestrogen consumption reduces weight in healthy postmenopausal adults but not in those with comorbid conditions (98870). However, the clinical validity of this analysis is limited because it did not evaluate the effect of soy-only phytoestrogens. Soy protein has also been compared with whey protein. One small clinical study in overweight and obese adults shows that patients taking soy protein isolate 52 grams for 23 weeks had similar overall weight and fat loss as those taking whey protein concentrate 52 grams daily (86077). In contrast, another small clinical study in overweight males shows that taking soy isolate 60 grams before lunch daily for 12 weeks is less effective for weight loss when compared with taking whey protein concentrate 65 grams (91801).
• Osteoarthritis. It is unclear if oral soy protein reduces osteoarthritis pain. Details: Preliminary clinical research shows that taking soy protein 40 grams daily for three months improves range of motion, pain, and quality of life in osteoarthritis patients, particularly males, when compared to baseline. However, these beneficial effects seem to also be observed following supplementation with milk-based protein, indicating that the benefits may have resulted from a placebo effect (75266).
• Overall mortality. It is unclear if dietary soy reduces overall mortality; the available research is conflicting. Details: A meta-analysis of observational studies has found that the highest intake of soy products is not associated with a lower risk of overall mortality, mortality from cardiovascular disease, or mortality from cancer when compared with the lowest intake (96941). However, a more recent population study has found that consuming at least 60 grams of soy daily over a 12-month period is associated with a 17% reduced risk of overall mortality over the next 5 years when compared with consuming less than 15 grams daily (108253). Also, an observational study in Japanese patients followed over 14.8 years has found that although overall soy intake is not associated with any benefit, increased intake of fermented soy products, such as natto and miso, was found to be associated with a slightly reduced risk of mortality (105600).
• Polycystic ovary syndrome (PCOS). It is unclear if oral soy reduces PCOS symptoms. Details: Clinical research shows that taking soy isoflavones 50 mg daily for 12 weeks improves insulin levels and insulin resistance by a small amount when compared with placebo in patients with PCOS. Furthermore, taking soy isoflavones improves the free androgen index by approximately 25% and triglyceride levels by 14% when compared to baseline. However, taking soy isoflavones does not improve low- or high-density lipoprotein (LDL or HDL) cholesterol levels or markers of inflammation (95994).
• Postmenopausal conditions. It is unclear if oral soy is beneficial for postmenopausal conditions. Details: A meta-analysis of generally small clinical trials in postmenopausal adults shows that taking soy protein with isoflavones or soy isoflavones, usually for 3-24 months, has modest beneficial effects on total cholesterol, and possibly high-density lipoprotein (HDL) cholesterol, when compared with milk protein, soy protein without isoflavones, or placebo. However, there was no effect on low-density lipoprotein (LDL) cholesterol or triglyceride levels. Subgroup analyses show that reductions in LDL cholesterol levels occur when soy is used for less than 6 months, in individuals older than 55 years, and when the soy protein contains isoflavones (108249).
• Preterm labor. It is unclear if oral soy reduces the risk for preterm labor. Details: Clinical research in patients with gestational diabetes shows that consuming a diet containing soy protein along with other plant and animal proteins for 6 weeks, beginning at 24-28 weeks' gestation, does not reduce the likelihood for caesarean section, preterm delivery, or maternal hospitalization when compared with a control diet containing only non-soy plant and animal proteins (95993).
• Premenstrual syndrome (PMS). It is unclear if oral soy reduces PMS symptoms. Details: Preliminary clinical research in patients with PMS shows that taking isolated soy protein containing soy isoflavones 68 mg daily for two menstrual cycles reduces cramps and swelling when compared with placebo (75279).
• Prostate cancer. It is unclear if oral soy is beneficial for the treatment or prevention of prostate cancer; research is conflicting. Details: Observational and clinical research has evaluated the effects of soy intake on prostate cancer risk. Observational research has found that consuming an Asian diet, which contains 10 times more soy than the average American diet, is associated with a lower risk of prostate cancer; however, it is unclear whether it is the soy content of the diet or if genetic differences or environmental factors such as fat ingestion are responsible for this correlation (2298,12884,12886,12887). A meta-analysis of observational trials from North America, Europe, and Asia has found that highest intake of total soy foods, unfermented soy foods, or soy isoflavones is associated with a reduced risk of prostate cancer when compared with the lowest intakes. However, higher intake of fermented soy foods is not associated with a reduced risk (96939). Furthermore, some observational research in Japanese males has found a weak association between increased prostate cancer mortality and a higher dietary intake of soy isoflavones when compared with a lower intake (105607). Research evaluating the use of soy supplements is also conflicting. One clinical study shows that taking soy protein 40 grams daily for 6 months reduces the development of prostate cancer six-fold in those at risk of prostate cancer when compared with milk protein (75432). However, another clinical study in healthy adults aged 50-80 years shows that taking soy protein, providing 83 mg isoflavones, daily for a year does not affect PSA levels when compared with a soy protein drink without isoflavones (12888). Soy products have also been evaluated in patients with prostate cancer. One clinical study shows that consuming a specific bread containing 50 grams of soy, providing 117 mg isoflavones, reduces PSA levels after about 3 weeks of treatment when compared with control (13140). Other preliminary clinical research in patients with rising PSA levels following prior therapy for prostate cancer shows that consuming 8 ounces of soy milk, standardized to contain 47 mg isoflavones, three times daily for 12 months slows the increase in PSA levels from 56% to 20% when compared with baseline (75435). However, one clinical study shows that taking soy protein 40 grams daily for 6 months does not reduce prostate size or improve PSA levels in those diagnosed with prostate cancer when compared with milk protein (75432). Also, in those with early stage prostate cancer, consuming a soy beverage daily providing genistein 60 mg does not seem to affect risk factors for progression of prostate cancer, including testosterone, estradiol, PSA, and sex hormone binding globulin (SHBG) levels (11033). Furthermore, consuming soy protein isolate 20 grams standardized to contain approximately 70 mg isoflavones daily for two years does not prevent prostate cancer recurrence following radical prostatectomy when compared with placebo (90953). Reasons for the discrepancies are not entirely clear, but may include the relatively short trial durations (up to 12 months) and heterogeneity of soy preparations and dosing regimens.
• Rheumatoid arthritis (RA). It is unclear if oral soy reduces RA symptoms. Details: Preliminary clinical research in patients with RA shows that consuming a liquid diet containing hydrolyzed soy protein (Top Up) daily for 4 weeks does not improve pain intensity, morning stiffness, or joint swelling and tenderness when compared to consuming a normal daily diet (75619).
• Sarcopenia. It is unclear if oral soy reduces age-related muscle loss; evidence is conflicting. Details: Some clinical research in postmenopausal adults shows that consuming soy protein containing isoflavones 99 mg daily for 12 months does not improve hand grip strength or physical performance when compared with a milk protein placebo (75283). However, another small clinical study in older adults with low muscle mass living in China shows that taking soy, or a whey-soy blended protein, 16 grams daily for 6 months, slightly attenuates muscle loss when compared with no intervention (105603).
• Stroke. It is unclear if oral soy improves outcomes and overall function in people who have had a stroke. Details: One small clinical study shows that older adults with a history of stroke who consumed soy milk 500 mL daily while participating in a rehabilitation program had greater improvements in hand grip strength, 8-feet walking speed, walking performance, and 6-minute walk test after 8 weeks when compared with placebo. However, consuming soy milk did not lead to greater improvements in lean mass or overall short physical performance battery (SPPB) scores when compared with placebo (100321).
• Thyroid cancer. It is unclear if dietary soy reduces the risk for thyroid cancer. Details: Epidemiological research has found that high dietary intake of soy is associated with a reduced risk of thyroid cancer when compared with lower intake (7662,12041).
• Vaginal atrophy. It is unclear if topical soy improves vaginal atrophy. Details: A small clinical study in postmenopausal adults with vaginal atrophy shows that applying one gram of soy extract 4% vaginal gel daily for 12 weeks reduces vaginal dryness and pain during sexual intercourse and improves vaginal endometrial thickness when compared with placebo (90964).
• Wrinkled skin. Small studies suggest that oral and topical soy might reduce wrinkles. Details: A small clinical study in middle-aged females shows that consuming soy isoflavone 40 mg daily for 12 weeks improves skin elasticity and the appearance of fine wrinkles when compared with placebo (75388). Another small clinical study in females with photodamaged skin shows that applying a soy moisturizer containing soybean trypsin inhibitor and Bowman-Birk protease inhibitor (Aveeno Positively Radiant Daily Moisturizer, Johnson & Johnson CCI) twice daily for 12 weeks improves skin pigmentation, fine lines, texture, tone, and appearance when compared with a placebo moisturizer (75410). More evidence is needed to rate soy for these uses.

(Read more about SOY)

POSSIBLY EFFECTIVE

• Athletic performance. Regular consumption of whey protein in conjunction with exercise may improve muscle strength and performance. However, inconsistent consumption of whey protein, as well as intake of whey protein without concomitant exercise, may not be beneficial. Details: Most clinical research shows that taking whey protein 1.2-1.5 grams/kg or 30-33 grams daily in combination with strength training for 6-21 weeks can increase lean body mass, strength, and muscle hypertrophy in healthy young adults (16728,16729,16748,46552,85765,85910,91806,96025,102173). Higher doses of whey protein, such as 46-77 grams daily, have also been shown to increase strength when combined with athletic training (98886,98888). Some clinical research shows that whey protein hydrolysate (Lacprodan HYDRO.365, Arla Food Ingridiens Group P/S) twice daily for 1 week may slightly improve running speed (91793). However, less frequent intake or lower doses of whey protein do not seem to be beneficial for muscle strength. Some clinical research in middle-aged males shows that taking whey protein 35 grams three times weekly with resistance training for 14 weeks does not improve strength or muscle mass when compared with placebo (46736,85893). A small clinical study in trained males shows that taking whey protein 25 grams daily has no effect on body mass or strength after 2 weeks of detraining and 4 weeks of retraining when compared with maltodextrin (96021). Also, consuming whey protein without concomitant exercise does not seem to improve body composition or strength. Some clinical research shows that whey protein does not improve muscle mass or strength in obese postmenopausal patients who are losing weight through diet without exercise (98889). Some research has compared whey protein to other types of protein. A meta-analysis of preliminary clinical research, as well as individual clinical studies, show that whey protein is similarly beneficial to soy, beef, chicken, and dairy (casein with whey) protein for improving muscle strength (85941,98871,98888,105591). However, the validity of these findings is limited by the small size and high heterogeneity of the studies.

POSSIBLY INEFFECTIVE

• Chronic obstructive pulmonary disease (COPD). Oral whey protein does not seem to improve COPD symptoms. Details: Clinical research in adults with COPD shows that taking a specific whey protein supplement (ImuPower) 12 grams twice daily for 6 weeks can improve shortness of breath, but not lung function, exercise tolerance, or quality of life, when compared with placebo (86302). Other clinical research shows that taking a pressurized whey protein supplement 20 grams daily for 16 weeks, in combination with strength training for weeks 8-16, does not improve exercise tolerance, lung function, or muscle function when compared with placebo (86025).
• Osteoporosis. Oral whey protein does not seem to improve bone mineral density in older adults. Details: Clinical research shows that taking whey protein 30-45 grams daily for up to 2 years does not improve bone density when compared with a low-protein placebo in postmenopausal patients and males over 70 years of age (86074,91796). Taking whey protein 20-60 grams daily for 36 weeks also does not improve bone density when compared with an isoenergetic placebo in overweight or obese adults undergoing an exercise program (96027). The effect of whey protein in patients with osteoporosis has not been evaluated.

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Age-related cognitive decline. It is unclear if oral whey protein is beneficial for age-related cognitive impairment. Details: Preliminary clinical research in older adults with subjective cognitive decline shows that taking whey peptide 1 gram for 12 weeks does not improve memory, executive functioning, or attention when compared with placebo. However, in a subgroup of patients with high levels of fatigue, whey peptide modestly improved memory (98885).
• Asthma. It is unclear if oral whey protein is beneficial in children with asthma. Details: A very small clinical study in children with asthma shows that taking a specific type of whey protein (HMS 90, Immunotec Inc.) 20 grams daily for 30 days does not improve lung function when compared to baseline (85833). The validity of this finding is limited by the lack of a comparator group.
• Atopic dermatitis (eczema). It is unclear if consuming infant formula containing whey protein reduces the risk of developing eczema. Details: A high-quality meta-analysis of small clinical studies shows that use of infant formula containing hydrolyzed whey protein for 4-6 months is no better than standard milk formula for reducing the risk of eczema (105585). This is in contrast to older meta-analyses that found benefit after consumption of fully or partially hydrolyzed whey protein (85987,86007,86048). However, these older publications had notable conflicts of interest and did not include small negative studies (105585). In 2011, the US Food and Drug Administration (FDA) allowed a qualified health claim in healthy infants with a family history of allergy who are not solely breastfed. It stated that feeding a formula of 100% partially hydrolyzed whey protein instead of formula containing intact cow's milk proteins from birth up to 4 months of age may reduce the risk of atopic dermatitis throughout 1-3 years of age. However, the FDA has concluded that there is very little scientific evidence to support this claim (102311).
• Atopic disease. It is unclear if consuming infant formula containing whey protein reduces the risk of developing atopic disease. Details: A high-quality meta-analysis of small clinical studies shows that use of infant formula containing hydrolyzed whey protein for 4-6 months is no different than standard milk formula for reducing the risk of atopic disease. However, there was a non-significant trend to reduced risk in the hydrolyzed whey protein group (105585). This finding conflicts with older meta-analyses which found benefit with hydrolyzed whey protein formula (85987,86007). However, these older publications had notable conflicts of interest and did not include small negative studies (105585).
• Cystic fibrosis. It is unclear if oral whey protein is beneficial for children or adults with cystic fibrosis. Details: A small clinical study in patients with cystic fibrosis shows that taking pressurized whey protein, 20 grams in children and 40 grams in adults, daily for 28 days, improves lung function in children, but not adults, when compared with baseline (85995). The validity of this finding is limited by the lack of a comparator group.
• Diabetes. It is unclear if oral whey protein is beneficial for improving glycemic control in people with type 2 diabetes. Details: A small clinical study in patients with well-controlled diabetes shows that consuming a 220 kcal drink containing whey protein concentrate 50 grams (Beit Haemek Advanced Technologies, Beit Haemek) before a meal lowers blood glucose levels by 28% and increases insulin levels in the first 3 hours after a meal when compared with drinking water (91795). However, whey protein does not seem to have long-term benefit on glycemic control when added to an exercise regimen. Another small clinical study in middle-aged males with type 2 diabetes shows that adding 20 grams of whey protein daily for 10 weeks to high-intensity mixed-mode interval training (MMIT) does not further improve glycemic control or body composition when compared to MMIT with placebo (98883).
• Exercise-induced asthma. It is unclear if oral whey protein is beneficial for exercise-induced asthma. Details: A small clinical study in patients with exercise-induced asthma shows that taking whey protein 30 grams daily for 10 days improves lung function when compared to baseline (85791). The validity of this finding is limited by the lack of a comparator group.
• Exercise-induced muscle damage. It is unclear if oral whey protein is beneficial for attenuating exercise-induced muscle damage; evidence is conflicting. Details: A meta-analysis of small heterogeneous clinical studies in trained and untrained adults shows that supplementation with a median dose of whey protein 25 grams (range 20-120 grams) given after and/or before exercise modestly improves muscle recovery measured over 3 days when compared with control (98881). Individual studies included in the analysis used whey protein 1.5 grams/kg daily for up to 2 weeks (86044), and whey protein isolate or whey protein hydrolysate (NatraPro or NatraBoost XR, MG Nutritionals) 25 grams three times in 24 hours (85915). Other small studies have not found benefit, but it is unclear if they were adequately powered. One small clinical study in healthy untrained males shows that taking whey protein 36.6 grams daily, starting 7 days before and continuing until 4 days after arm exercise, does not prevent muscle soreness over 5 days or attenuate reductions in strength (96024). Another small study in untrained healthy males shows that taking whey protein isolate (biPro, Eden Prairie) 0.3 grams/kg three times daily for 5 days does not reduce self-reported delayed onset muscle soreness, but may reduce creatine kinase, a biomarker of muscle damage, when compared with water (104758). Whey protein may not be beneficial for recovery from exercise in trained athletes. Small clinical studies show that consuming a whey protein beverage before or after exercise does not improve muscle recovery for trained adult and adolescent athletes when compared with a carbohydrate or non-caloric control (86303,91799,105592).
• Hepatitis. It is unclear if oral whey protein is beneficial for hepatitis. Details: A small clinical study in patients with chronic hepatitis B shows that taking a specific type of whey protein (Immunocal) 12 grams twice daily for 12 weeks can reduce liver transaminase levels and can increase glutathione (GSH) levels when compared with baseline. However, whey protein supplementation does not seem to improve liver function in patients with chronic hepatitis C (85687). The validity of these findings is limited by the lack of a comparator group.
• HIV/AIDS. It is unclear if oral whey protein is beneficial for improving immune function in children with HIV/AIDS. Details: One small clinical study in children with rapidly progressive HIV infection shows that taking whey protein at levels corresponding to 20% to 50% of total required protein for 4 months does not affect CD4 or CD8 cell count or the ratio of CD4+/CD8+ when compared with baseline. However, the occurrence of acute co-infections might be reduced with whey protein supplementation when compared with control (85781).
• HIV/AIDS-related wasting. Although oral whey is an adequate source of protein, it is unclear if it is better than other protein sources for reducing HIV/AIDs-related wasting. Details: A small open-label clinical study in malnourished patients with HIV shows that taking whey protein (dose unspecified) daily for 14 weeks increases muscle and fat mass when compared with baseline (85693). The validity of these findings is limited by the lack of a comparator group. Another small study in patients with HIV, stable weight, and a history of unintentional weight loss shows that taking whey protein 40 grams daily for 12 weeks does not affect weight or muscle mass when compared with taking an isocaloric control (85921). These study findings are limited because they cannot be generalized to patients with active weight loss or wasting. Another limitation is the higher dropout rate in the whey protein group due to gastrointestinal adverse events.
• Hyperlipidemia. It is unclear if oral whey protein is beneficial for lowering cholesterol levels. Details: A very small clinical study in overweight males with hyperlipidemia shows that taking whey protein 26.6 grams daily while participating in a resistance training program for 12 weeks reduces total cholesterol levels when compared with baseline but not when compared with placebo (85941). A meta-analysis of small heterogeneous clinical studies in healthy adults, as well as those with obesity and/or mild hypertension, shows that consuming whey protein alone or with other interventions seems to reduce lipid levels when compared with control (105586). However, most included studies were in patients without hyperlipidemia; it is unclear if whey protein is beneficial in patients with hyperlipidemia. Furthermore, these findings are limited by the variability in whey protein dosing, study duration, and patient population.
• Hypertension. It is unclear if oral whey protein reduces blood pressure. Details: Preliminary clinical research shows that drinking a beverage containing whey protein 2.6 grams daily for 12 weeks does not lower blood pressure in patients with mild hypertension when compared with placebo (85835). Also, taking whey protein 28 grams twice daily in water for 8 weeks reduces 24-hour systolic and diastolic blood pressure by 2.9 mm Hg and 2 mmHg, respectively, when compared with maltodextrin or casein in adults with mild hypertension and prehypertension. There were also improvements in endothelial function (96019).
• Mitochondrial myopathies. It is unclear if oral whey protein improves symptoms in patients with mitochondrial myopathies. Details: A small clinical study in individuals with mitochondrial diseases shows that taking a whey protein supplement 10 grams daily for one month does not improve muscle strength or quality of life when compared with placebo (85984).
• Nonalcoholic steatohepatitis (NASH). It is unclear if oral whey protein improves NASH. Details: A small clinical study in patients with untreated NASH shows that taking whey protein 20 grams daily for 12 weeks can reduce liver function tests, including alanine aminotransferase (ALT) and aspartate aminotransferase (AST), and reduce hepatic macrovesicular steatosis when compared with baseline (85961). The validity of these findings is limited by the lack of a comparator group.
• Obesity. It is unclear if oral whey protein is beneficial for weight loss when used without dietary modifications. Adding whey protein to a calorie-restricted diet or an exercise regimen does not seem to improve weight loss. Details: Most research in overweight and obese individuals shows that taking whey protein along with a low-calorie diet and/or in addition to an exercise program does not further increase weight loss when compared with the low-calorie diet or exercise alone (85897,86069,86130,91794,91798,91802,96027,102172). However, a small clinical study in patients who have regained weight after bariatric surgery shows that following a low-calorie diet and taking whey protein 0.5 grams/kg daily for 16 weeks reduces body weight by about 2 kg and fat mass by about 3 kg when compared with following a low-calorie diet alone (96022). When whey protein is taken without diet modifications, studies have yielded conflicting results. One small clinical study in overweight and obese adults shows that taking whey protein isolate 27 grams twice daily for 12 weeks does not reduce body weight when compared with a glucose control (86011). However, another small clinical study in overweight and obese adults shows that taking whey protein concentrate 52 grams daily for 23 weeks reduces weight by 1.8 kg and fat by 2.4 kg when compared with a carbohydrate control, but is no better than taking soy protein isolate 52 grams (86077). In contrast, a small clinical study in overweight males shows that taking whey protein concentrate 65 grams before lunch daily for 12 weeks decreases calorie intake and reduces weight by about 1 kg when compared with taking soy protein isolate 60 grams (91801). In contrast to adults, supplementation with whey protein might increase weight in adolescents. A clinical study in overweight adolescents shows that consuming 1 liter of a milk-based whey protein drink daily for 12 weeks increases weight and body mass index when compared with a water control (86144).
• Parkinson disease. It is unclear if oral whey protein improves symptoms of Parkinson disease. Details: Clinical research in a small group of patients shows that taking a specific type of whey protein isolate (HMS 90/Immunocal) 10 grams twice daily for 6 months does not improve symptoms of Parkinson disease when compared with placebo (96026). However, this study may have been inadequately powered to detect a difference between groups.
• Polycystic ovary syndrome (PCOS). It is unclear if oral whey protein improves symptoms and metabolic effects of PCOS. Details: One small clinical study in patients with PCOS shows that taking 240 kcal as a nutritional supplement containing pure whey protein 96% daily, in addition to a calorie-restricted diet for 2 months, reduces body weight, fat mass, and cholesterol and apolipoprotein B levels when compared with a simple sugar control supplement. However, the whey protein supplement does not improve glucose or insulin levels, and seems to decrease high-density lipoprotein (HDL) cholesterol levels (85912). The validity of this study is limited by its small size and a significant dropout rate.
• Polymyalgia rheumatica. It is unclear if oral whey protein improves muscle function in patients with polymyalgia rheumatica. Details: A small clinical study in patients with polymyalgia rheumatica shows that taking a whey protein-enriched dairy product twice daily for 8 weeks does not improve lower limb muscle function, walking speed, chair stand test performance, peak jump power, or peak jump force when compared with a regular dairy product (Play, Valio Ltd.) (86075).
• Psoriasis. It is unclear if oral whey protein improves psoriasis. Details: A small clinical study in patients with stable psoriasis shows that taking a specific whey protein extract product (Dermylex, Advitech, Inc.) 5 grams daily for 8 weeks modestly decreases symptom severity when compared with placebo (85885).
• Sarcopenia. Research on the use of oral whey protein in older adults with sarcopenia is conflicting. Details: Small clinical studies in trained older females show that consuming whey protein 35 grams three times weekly for 12 weeks, either before or after resistance training, modestly increases skeletal muscle mass, strength, and functional capacity when compared with resistance training and insufficient protein intake (98887,98890). Research on the use of whey supplementation without exercise is conflicting. A small clinical study in older adults with low muscle mass living in China shows that taking whey, or a whey-soy protein blend, 16 grams daily for 6 months slightly attenuates muscle loss when compared with no intervention (105603). However, a clinical study in healthy, active older adults living in Denmark shows that taking whey protein hydrolysate 20 grams twice daily does not increase muscle size or strength when compared with a carbohydrate control (105593). This finding may not be generalizable to frail adults or those with existing sarcopenia. Whey protein with or without exercise has shown benefit when used in combination with other nutrients. Specifically, whey protein 60 grams has been used with creatine 5 grams, calcium 800 mg, vitamin D 1000 IU, and omega-3 fatty acids 3 grams (Infinit Nutrition) for 6 weeks (96016). A beverage with leucine-enriched whey protein 20 grams has been used in combination with vitamin D 800 IU (Nutricia Advanced Medical Nutrition) daily for 6 weeks (96017). Another beverage containing whey protein 20 grams and vitamin D 800 IU has been used daily for 6 months (98882).
• Sepsis. It is unclear if oral whey protein is beneficial in children with sepsis. Details: A very small clinical study in long-term intensive care pediatric patients shows that taking a specific whey protein supplement (Beneprotein) 0.3 grams/kg daily for up to 28 days has a similar effect on the time to onset and the rate of hospital-acquired infection or sepsis when compared with taking a combination of zinc, selenium, glutamine, and metoclopramide. It is not clear how these results compare to patients receiving no supplementation (86095). More evidence is needed to rate whey protein for these uses.

(Read more about WHEY PROTEIN)

LIKELY SAFE ...when used orally and appropriately. Casein peptides have been safely used in clinical trials lasting up to 5 months (85648,103763,103764,103765,103770,103772).

CHILDREN: LIKELY SAFE
when used orally and appropriately. Casein peptide formulas have been safely used in healthy, premature, and very low birth weight infants (91262,91264,91643,91673,91675).

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

(Read more about CASEIN PEPTIDES)

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

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

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

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

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

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

(Read more about COCOA)

LIKELY SAFE ...when used rectally and appropriately. Glycerol rectal suppositories and enemas are approved by the US Food and Drug Administration (FDA) for over-the-counter use to treat occasional constipation (15,272). ...when used topically and appropriately as a lotion, emulsion, or humectant (15,272,93754,93758,93759,99164).

POSSIBLY SAFE ...when used orally, short-term. Glycerol has been used with apparent safety in clinical trials at doses of up to 1.5 grams/kg (2474,2475,99162).

POSSIBLY UNSAFE ...when used intravenously. While some research suggests that intravenous glycerol can be safely administered for two consecutive days twice monthly for up to 6 months (106649), in another study, hemolysis was reported in 98% of patients treated with intravenous glycerol for acute ischemic stroke (2482).

CHILDREN: LIKELY SAFE
when used rectally and appropriately. Glycerol rectal suppositories and enemas are approved by the US FDA for over-the-counter use to treat occasional constipation in children 2 years of age and older (15,272). ...when used topically and appropriately as an emulsion or humectant in children 1 month of age and older (15,272,93756).

CHILDREN: POSSIBLY SAFE
when used orally, short-term. Glycerol has been used with apparent safety in clinical trials in children 2 months to 16 years of age at doses of 1.5 gram/kg, up to a maximum dose of 25 grams, taken every 6 hours (93762,93763).

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

(Read more about GLYCEROL)

LIKELY SAFE ...when used orally and appropriately in amounts commonly found in foods. Gum arabic has Generally Recognized As Safe (GRAS) status for use in foods in the US. It is also considered to be safe for use as a food additive by the European Food Safety Authority (4912,105040).

POSSIBLY SAFE ...when used orally and appropriately in medicinal amounts (8072). Up to 30 grams daily of powdered gum arabic has been used with apparent safety for 3 months (18237,99098,105040).

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using in amounts greater than those found in foods (4912,105040).

(Read more about GUM ARABIC)

LIKELY SAFE ...when used orally in amounts commonly found in foods. Lecithin has Generally Recognized As Safe (GRAS) status in the US (2619,105544). ...when used orally and appropriately in medicinal amounts. Lecithin has been used safely in doses of up to 30 grams daily for up to 6 weeks (5140,5149,5152,5156,14817,14822,14838,19212). ...when used topically (4914).

PREGNANCY AND LACTATION: LIKELY SAFE
when used orally in food amounts. Lecithin has Generally Recognized As Safe (GRAS) status in the US (105544). There is insufficient reliable information available about the safety of medicinal amounts of lecithin during pregnancy or lactation; avoid using.

(Read more about LECITHIN)

LIKELY SAFE ...when soy protein is used orally and appropriately. Soy protein products in doses up to 60 grams, providing up to 185 mg isoflavones, daily have been safely used in studies lasting up to 16 weeks (842,2293,2294,2296,3025,3402,3977,4755,6412,8530)(10372,11805).

POSSIBLY SAFE ...when soy extracts are used orally and appropriately, short-term. Soy extracts containing concentrated isoflavones in doses of 35-120 mg daily have been used with apparent safety for up to 6 months (4751,6455,7802,12040,12048,13209,95994,95999).

CHILDREN: LIKELY SAFE
when consumed in amounts commonly found in foods or as a component of infant formula (3400,4912,7331). Soy milk that's not designed for infants should not be used as a substitute for infant formula. Regular soy milk can lead to nutrient deficiencies (12045). Most evidence shows that exposure to soy formula or other soy products in infancy does not cause early onset of puberty or health or reproductive problems later in life (7331,11080,108245). However, some small cohort studies have suggested that higher soy intake during childhood may be associated with an increased risk of precocious puberty (108240) and may be weakly correlated with the development of breasts in children less than 2 years of age (75520). This is in contrast to an observational study in Chinese children ages 7-9 years which suggests that higher soy intake is associated with delayed puberty (108252). One small cohort study has also found that use of soy infant formula may be associated with an increased risk of endometriosis in adulthood, although endometriosis was also correlated with prematurity, which may have confounded the findings (101803).

CHILDREN: POSSIBLY UNSAFE
when used orally as an alternative to cow's milk in children with severe milk allergy (75359). Although soy protein-based infant formulas are often promoted for children with milk allergy, children with a severe allergy to cow's milk are also frequently sensitive to soy protein (9883). There is insufficient reliable information available about the safety of soy products when used in amounts higher than typical food quantities for children.

PREGNANCY: LIKELY SAFE
when used orally in amounts commonly found in foods (4912).

PREGNANCY: POSSIBLY UNSAFE
when used orally in medicinal amounts. Soy contains mildly estrogenic constituents (3373,3988,3989,3990,3994,6029,75303). Theoretically, therapeutic use of soy might adversely affect fetal development; avoid using.

LACTATION: LIKELY SAFE
when used orally in amounts commonly found in foods (4912). A single 20-gram dose of roasted soybeans, containing 37 mg isoflavones, produces four to six times less isoflavones in breast milk than provided in a soy-based infant formula (2290). There is insufficient reliable information available about the safety of long-term use of therapeutic amounts of soy during lactation.

(Read more about SOY)

LIKELY SAFE ...when used orally and appropriately. Whey protein up to 30 grams has been safely used in clinical trials for up to 6 months (4930,16728,16729,105587).

CHILDREN: LIKELY SAFE
when used orally and appropriately as a dietary protein in food or infant formula. Hydrolyzed whey protein-based formula has been safely used in infants for up to 6 months in clinical trials (4927,105585,105594).

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

(Read more about WHEY PROTEIN)

ANTIHYPERTENSIVE DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = B Theoretically, combining these casein peptides with antihypertensive drugs might increase the risk of hypotension.  Details Clinical research shows that some casein peptides, including the lactotripeptides isoleucine-proline-proline (IPP) and valine-proline-proline (VPP), can modestly reduce blood pressure in patients with hypertension (103763,103765,103770,103772).

(Read more about CASEIN PEPTIDES)

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

(Read more about COCOA)

(Read more about GLYCEROL)

AMOXICILLIN (Amoxil, Trimox) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Gum arabic can reduce the absorption of amoxicillin.  Details A small study in healthy volunteers shows that taking amoxicillin and gum arabic concurrently significantly reduces the absorption of amoxicillin. Separate doses of amoxicillin from gum arabic by at least 2 hours (12654).

ORAL DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, gum arabic can alter the absorption of oral drugs due to its fiber content.  Details Gum arabic has been used as a suspending osmotic agent in drug formulations. It might improve bioavailability of water-insoluble drugs like naproxen, but reduce absorption of polar drugs like amoxicillin (12654,104058). To avoid changes in absorption, take gum arabic 30-60 minutes after oral medications.

(Read more about GUM ARABIC)

(Read more about LECITHIN)

ANTIBIOTIC DRUGS Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, antibiotics may decrease the activity of soy isoflavones.  Details Intestinal bacteria are responsible in part for converting soy isoflavones into their active forms. Antibiotics may decrease the amount of intestinal bacteria and decrease its ability to convert isoflavones (7657).

ANTIDIABETES DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = A Soy can lower blood glucose and have additive effects with antidiabetes drugs.  Details Clinical research shows that whole soy diets and soy-based meals reduce fasting glucose levels in diabetic and non-diabetic individuals (75268,75296,75378,75493,96001). Also, individuals following a soy-based meal replacement plan seem to require lower doses of sulfonylureas and metformin to manage blood glucose levels when compared with individuals following a diet plan recommended by the American Diabetes Association (75268).

ANTIHYPERTENSIVE DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = A Theoretically soy protein may have additive effects with antihypertensive drugs and increase the risk of hypotension.  Details Although some contradictory research exists (14254), most clinical evidence suggests that consuming soy protein modestly reduces systolic and diastolic blood pressure in individuals with prehypertension or hypertension (13139,75482).

CAFFEINE Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, soy might reduce the clearance of caffeine.  Details Soy contains genistein. Taking genistein 1 gram daily for 14 days seems to inhibit caffeine clearance and metabolism in healthy females (23582). This effect has been attributed to inhibition of the cytochrome P450 1A2 (CYP1A2) enzyme, which is involved in caffeine metabolism. It is unclear if this effect occurs with the lower amounts of genistein found in soy.

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES Interaction Rating = Minor Be watchful with this combination. Severity = Moderate •  Occurrence = Unlikely •  Level of Evidence = D Soy might modestly induce CYP2C9 enzymes. However, this effect does not seem to be clinically significant.  Details In vitro research suggests that an unhydrolyzed soy extract might induce CYP2C9. However, the significance of this interaction is likely minimal. In healthy females taking a specific extract of soy (Genistein Soy Complex, Source Naturals), blood levels of losartan, a CYP2C9 substrate, were not significantly affected (16825).

DIURETIC DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, soy might have additive effects when used with diuretic drugs.  Details Animal research suggests that genistein, a soy isoflavone, increases diuresis within 6 hours of subcutaneous administration in rats. The effects seem to be similar to those of furosemide (75604). This effect has not been reported in humans.

ESTROGENS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, soy might competitively inhibit the effects of estrogen replacement therapy.  Details Soy contains phytoestrogens and has been shown to have estrogenic activity in some patients (3860). Although this has not been demonstrated in humans, theoretically, concomitant use of soy with estrogen replacement therapy might reduce the effects of the estrogen replacement therapy.

LEVOTHYROXINE (Synthroid, others) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Soy products might reduce the absorption of levothyroxine in some patients.  Details Preliminary clinical research and a case report suggest that soy-based formulas inhibit the absorption of levothyroxine in infants with congenital hypothyroidism (20636,20637,75548,90959). A levothyroxine dosage increase may be needed for infants with congenital hypothyroidism while using soy-based formulas, and the dose may need to be reduced when soy-based formulas are no longer administered. However, in postmenopausal adults, clinical research shows that taking a single dose of soy extract containing isoflavones 60 mg along with levothyroxine does not affect the oral bioavailability of levothyroxine (95996).

MONOAMINE OXIDASE INHIBITORS (MAOIs) Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Likely •  Level of Evidence = C Taking soy products containing high amounts of tyramine along with MAOIs can increase the risk of hypertensive crisis.  Details Fermented soy products such as tofu and soy sauce contain tyramine, a naturally occurring chemical that affects blood pressure regulation. The metabolism of tyramine is decreased by MAOIs. Consuming more than 6 mg of tyramine while taking an MAOI can increase the risk of hypertensive crisis (15649). The amount of tyramine in fermented soy products is usually less than 0.6 mg per serving; however, there can be significant variation depending on the specific product used, storage conditions, and length of storage. Storing one brand of tofu for a week can increase tyramine content from 0.23 mg to 4.8 mg per serving (15649,15701,15702). Advise patients taking MAOIs to avoid fermented soy products that contain high amounts of tyramine.

PROGESTERONE Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = A Theoretically, combining soy isoflavones with transdermal progesterone may worsen bone density.  Details Clinical research suggests that significant bone loss may occur in females with osteoporosis who receive a combination of transdermal progesterone with soy milk containing isoflavones when compared with placebo, soy milk alone, or progesterone alone (69859).

TAMOXIFEN (Nolvadex) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = B Theoretically, estrogenic soy isoflavones might alter the effects of tamoxifen.  Details Laboratory research suggests that genistein and daidzen, isoflavones from soy, can antagonize the antitumor effects of tamoxifen under some circumstances (7072,14362,8966); however, soy isoflavones might have different effects when used at different doses. A relatively low in vitro concentration of soy isoflavones such as 1 microM/L seems to interfere with tamoxifen, whereas high in vitro concentrations such as those >10 microM/L might actually enhance tamoxifen effects. People on a high-soy diet have soy isoflavones levels ranging from 0.1-6 microM/L. Until more is known, advise patients taking tamoxifen to avoid therapeutic use of soy products.

WARFARIN (Coumadin) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, soy might interfere with the effects of warfarin.  Details Soy milk has been reported to decrease the international normalized ratio (INR) in a patient taking warfarin. The mechanism of this interaction is not known (9672). However, animal and in vitro research suggests that soy may also inhibit platelet aggregation (3992). Dosing adjustments for warfarin may be necessary.

(Read more about SOY)

BISPHOSPHONATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D Theoretically, whey protein might reduce the absorption of bisphosphonates.  Details Whey protein contains minerals such as calcium that bind bisphosphonates in the gut (9,12937). Advise patients to take bisphosphonates at least 30 minutes before whey protein, but preferably at a different time of day.

LEVODOPA Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = D Theoretically, whey protein might decrease levodopa absorption.  Details Small clinical studies show that concomitant ingestion of protein or high doses of leucine or isoleucine (100 mg/kg) and levodopa can exacerbate tremor, rigidity, and the "on-off" syndrome in patients with Parkinson disease (3291,3292,3293,3294,4944).

QUINOLONE ANTIBIOTICS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D Theoretically, whey protein might decrease quinolone absorption.  Details Whey protein contains minerals, such as calcium, that can bind to quinolones in the gut (9,10339). To avoid this interaction, advise patients to take oral quinolones at least 2 hours before or 4-6 hours after whey protein.

TETRACYCLINE ANTIBIOTICS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D Theoretically, whey protein might decrease tetracycline absorption.  Details Whey protein contains minerals, such as calcium, that bind to tetracyclines in the gut (9,1843). To avoid this interaction, advise patients to take oral tetracyclines at least 2 hours before or 4-6 hours after whey protein.

(Read more about WHEY PROTEIN)

General ...Orally, casein peptides are well tolerated in infants and adults. Adverse effects reported in clinical trials did not occur more frequently than with placebo.

(Read more about CASEIN PEPTIDES)

General ...Orally and topically, cocoa is generally well tolerated.
Most Common Adverse Effects:
Orally: Borborygmi, constipation, diuresis, gastrointestinal discomfort, headaches, and nausea.
Serious Adverse Effects (Rare):
Orally: Tachycardia.

Cardiovascular ...Some cases of increased heart rate have been reported with oral cocoa use (13161,42132).

Dermatologic ...In some cases, when taken orally, cocoa can cause allergic skin reactions (13161). Topically, cocoa butter has occasionally caused a rash. In animals, it has been shown to block pores and cause acne; however, this has not been found in humans (11).

Gastrointestinal ...In human trials, chocolate consumption was associated with a higher incidence of flatulence, irritable bowel syndrome, upset stomach, gastric upset, borborygmi (a gurgling noise made by fluid or gas in the intestines), bloating, nausea, vomiting, and constipation or obstipation (41986,42221,41921,1374,42220,1373,42099,42097,42156,42123,18229,42169,42111). Chocolate consumption has been implicated as a provoking factor in gastroesophageal reflux disease (GERD) (41974,42005,41946,1374). Unpalatability has been reported (42079,42169). Consumption of chocolate and other sweet foods may lead to increased dental caries (42129,42030).

Genitourinary ...In some cases, when taken orally, cocoa can cause increased urination (13161).

Neurologic/CNS ...In some cases, when taken orally, cocoa can cause shakiness and might trigger migraine and other headaches (13161,42169,92271).

Other ...Due to the high sugar and caloric content of chocolate, there is concern about weight gain in people who consume large amounts of chocolate (17187).

(Read more about COCOA)

General ...Orally, rectally, and topically, glycerol seems to be well tolerated. Intravenously, glycerol may be unsafe.
Most Common Adverse Effects:
Orally: Bloating, diarrhea, nausea, vomiting, dizziness, and headache.
Topically: Burning, irritation, and pruritus.
Intravenously: Hemolysis in patients with acute ischemic stroke.

Dermatologic ...Topically, glycerol has been reported to cause burning, irritation, and pruritus (93754,93756). Rectally, the regular administration of glycerol 50% enemas has been reported to cause generalized urticaria in at least two patients; in both patients, symptoms resolved after discontinuation (110019,110025).

Gastrointestinal ...Orally, glycerol can cause bloating, nausea, vomiting, thirst, and diarrhea (15,2475).

Hematologic ...Intravenously, glycerol has been reported to caused hemolysis in people treated for acute ischemic stroke (2480,2482).

Neurologic/CNS ...Orally, glycerol can cause mild headache and dizziness (15,2475).

(Read more about GLYCEROL)

General ...Orally, gum arabic seems to be generally well tolerated.
Most Common Adverse Effects:
Orally: Abdominal bloating, flatulence, mild diarrhea, nausea, and vomiting.

Gastrointestinal ...Orally, gum arabic can cause minor gastrointestinal disturbances such as abdominal bloating, flatulence, nausea, vomiting, cramping, and mild diarrhea (8072,18237,99098,105038,105040,108051). These effects occurred in 15%, 82%, and 90% of subjects respectively in one study (18237). They may subside with continued use within 2 weeks (8072,18237,99098,105038).

Immunologic ...Gum arabic might cause allergic reactions. In one case report, a patient had an immunoglobulin E response after exposure to gum arabic. However, there have been no identified case reports of allergic reactions after oral exposure to gum arabic (19636,105040).

(Read more about GUM ARABIC)

General ...Orally, lecithin is well tolerated.
Most Common Adverse Effects:
Orally: Abdominal pain, diarrhea, fullness, and nausea.

Dermatologic ...Orally, lecithin can cause allergic skin reactions in people with egg or soy allergies (15705).

Gastrointestinal ...Orally, lecithin may cause abdominal pain, diarrhea, fullness, and nausea (5140,6243,14817,14822,14838,19204,59281).

Neurologic/CNS ...Orally, lecithin caused CNS complaints and agitation in one patient in a clinical trial (59261).

(Read more about LECITHIN)

General ...Orally, soy is well tolerated.
Most Common Adverse Effects:
Orally: Bloating, constipation, diarrhea, and nausea.
All ROAs: Allergic reactions.

Endocrine ...In the 1950s and 1960s, cases of altered thyroid function, particularly goiter, were reported in children taking soy formula. However, adding iodine to soy formula or replacing soy flour in formula with soy protein isolate has nearly eliminated the risk of altered thyroid function in most infants (75353,75651).
In adults, there is some evidence that soy intake can alter thyroid function. Results from one clinical trial suggests that consuming soybeans 30 grams daily for as little as one month can increase thyroid-stimulating hormone (TSH) and decrease thyroxine, causing diffuse goiters, constipation, fatigue, and lethargy in some Japanese men. Recovery was achieved by discontinuing soybean intake (75206,75353). There is also some evidence that soy inhibits thyroid hormone synthesis resulting in increased secretion of TSH in some postmenopausal patients (7806). However, this seems to only occur in people with iodine deficiency (6466,75311). In postmenopausal patients with normal levels of iodine, taking a soy extract for 6 months does not seem to significantly affect thyroid hormone levels (13010).
Evidence from a single case-control study suggests that consumption of soy-based formulas may be associated with an observed three-fold increase in the risk of breast development in Puerto Rican children less than 2 years-old (75520). The correlation has been attributed to the estrogenic activity of soy. However, other risk factors, including a maternal history of ovarian cysts and consumption of meat products were also associated with the increased risk of breast development prior to 2 years of age. Also, the investigators noted that in over half of the cases, the child had not been exposed to soy or any of the other risk factors. Therefore, factors other than soy consumption may be more strongly associated with the increased risk of breast development prior to 2 years of age.

Gastrointestinal ...Gastrointestinal upset, such as constipation, diarrhea, bloating, and nausea are the most common side effects of soy (2297,11033,11082,15851,75491,95999). Reports of "bad taste" and taste intolerance have also been documented in clinical research (15851,39007,75491). Firmer stools, diarrhea, colitis, and intestinal mucosal damage has been reported in infants fed soy protein formula (75161,75448,75516,75525).

Genitourinary ...Orally, soy might increase discomfort during menstrual periods. Evidence from a small, retrospective cohort study has found that consuming soy formula as an infant may slightly increase the duration and discomfort of menstrual periods later in life. However, the investigators noted that these differences may not be clinically significant (7331).
Orally, frequent soy consumption might be a risk factor for uterine leiomyoma, an estrogen-dependent benign tumor located on the uterus. Observational research found that consumption of soy milk or soybean at least four times weekly is associated with a 7-fold increased odds of uterine leiomyoma (98869).
There is some concern that use of soy-based formulas in infants might result in long-term health complications. However, results from a retrospective cohort study has found that intake of soy-based formula as an infant does not affect height, weight, body mass index, pubertal maturation, menstrual history, or pregnancy history, nor does it increase the risk of reproductive organ disorders, hormonal disorders, libido dysfunction, or birth defects in the offspring of adults who received soy formula as infants (7331,11080). Additionally, research in adults shows that urinary phytoestrogens are not associated with endometriosis risk (101804). However, some population research has found that regular exposure to soy-based formulas during infancy is associated with an increased risk for endometriosis (101803).

Immunologic ...Orally, soy can cause allergic reactions such as skin rash and itching in some people (6412). In an 11-year-old female, allergy to soy protein resulting in a delayed itching papular rash was thought to be responsible for the reaction to injected benzathine benzylpenicillin containing possible soy protein-contaminated soy lecithin (96422).
Topically, soy-based ingredients were responsible for the development of hand atopic dermatitis in a young female using cosmetic lotions in the workplace. Percutaneous sensitization resulted in the development of anaphylaxis to oral soy (96000).

Neurologic/CNS ...Orally, one clinical study showed that insomnia was more common in postmenopausal adults taking soy isoflavone supplements when compared with those receiving placebo (9917). Some research suggests that dietary consumption of tofu during midlife might decrease cognitive function in later years. Evidence from one retrospective cohort study suggests that males who consume at least two servings of tofu weekly during midlife have increased risk of cognitive impairment in late life (19% vs. 4%) compared to those who consume tofu less frequently. Although the effect of tofu was considered to be marginal compared to other factors such as age, education, or history of stroke, results from the study suggest that the effect of significant midlife consumption of tofu is comparable to the effect of an age difference of 4 years or an education difference of 3 years. However, numerous other factors, such as lifestyle and health, could be involved (6415,6416). Therefore, these findings are too preliminary to be used as a basis for clinical recommendations.

Oncologic ...There is controversy about the role of soy in breast cancer. Population studies suggest that soy is protective against breast cancer. Asian females who eat a traditional diet high in soy seem to have a lower risk of developing breast cancer (4590,5939,9674). Early exploratory studies have suggested that soy stimulates proliferation of normal human breast tissue (3980,3981). However, taking a soy tablet containing 50 mg soy isoflavones daily for 12 months does not alter mammographic or breast MRI tissue density in adults at high risk of breast cancer, with non-endocrine treated breast cancer, or previously treated for breast cancer and without evidence of recurrence (95999).
There is some concern that soy supplements, but not soy foods, might increase the risk of endometrial hyperplasia due to its estrogenic effects. Population and clinical research suggests that soy foods do not have a proliferative effect on endometrial cells (7358,2429,7654,9676,9917), and increased dietary soy and phytoestrogens are associated with reduced endometrial cancer risk (7338,10372). However, the effects seem to be different with concentrated soy isoflavone extract. While taking products providing isoflavones 120 mg daily for 6 months does not increase endometrial thickening (13209), taking higher doses such as isoflavones 150 mg daily for 5 years might increase the risk of simple endometrial hyperplasia (12105). However, there is no evidence that soy isoflavones increase the risk of atypical hyperplasia which has a much higher risk of developing into endometrial cancer than simple endometrial hyperplasia (12105,90973).
There is also concern that increased soy intake increases the risk for other types of cancer. Some observational research has found that higher dietary intake of soy is associated with a higher risk for bladder cancer and pancreatic cancer (9677,105609).
A meta-analysis of results from cohort and case-control studies evaluating the risk of stomach cancer related to consumption of fermented soy products is unclear and inconclusive. The highest quality data from cohort studies suggests that these products have no significant effect on stomach cancer (7340,7341). More research is required to determine if soy products have any correlation with stomach cancer.

Pulmonary/Respiratory ...Inhaled soy dust and soy hull aeroallergen can trigger symptoms of asthma and allergic rhinitis (5084,5085,5086).

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General ...Orally, whey protein is generally well tolerated.
Most Common Adverse Effects:
Orally: Acne, bloating, cramps, diarrhea, fatigue, headache, nausea, reflux, reduced appetite, and thirst. Most adverse effects are dose-related.

Cardiovascular ...In one case report, use of an unclear quantity of whey protein over one month was thought to be probably responsible for the development of coronary embolism in three coronary arteries in a 33-year-old male with no history of atherosclerosis risk factors. The patient required treatment with intravenous glycoprotein IIb/IIIa inhibitor and heparin (96023).

Dermatologic ...Orally, whey protein has been reported to trigger the onset or worsening of acne. Multiple case reports in teenagers and young adults have associated intake of whey protein with the development of acne or the worsening of existing acneiform lesions. In these reports, the discontinuation of whey protein was typically associated with the clearance of acne lesions. In some cases, patients who were unresponsive to acne treatments while using whey protein became responsive after whey protein discontinuation (103965,103970,103971). Cow's milk, which is comprised of 20% whey protein, is also thought to exacerbate acne. It is theorized that this effect may be due to the growth factor and alpha-lactalbumin content of whey protein (103971,103982).

Gastrointestinal ...Orally, whey protein, especially in higher doses of 2. 3-6.5 grams/kg daily, may cause increased bowel movements, nausea, thirst, bloating, esophageal reflux, cramps, and reduced appetite (2640,85961,85702,86043,86074,86075,86084,86089,86095).

Hepatic ...In two case reports, acute cholestatic liver injury occurred after consumption of the combination of whey protein and creatine supplements (46701,90319).

Musculoskeletal ...In one case report, a 26-year-old male experienced fasciitis, or swelling of the forearms, hands, and legs, after consuming the supplement Pure Whey (85895).

Neurologic/CNS ...Orally, high doses of whey protein may cause tiredness or fatigue and headache (2640). Mild drowsiness has also been reported (86089,86092,86124).

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