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PubMedDate not supplied

The Dietary Supplement and Health Education Act and supplements: dietary and nutritional supplements need no more regulations.

The Dietary Supplement and Health Education Act (DSHEA) of 1994 was intended to ensure consumer access to safe dietary supplements, e.g., herbs, minerals, and vitamins. It granted the Food and Drug Administration (FDA) considerable enforcement authority to regulate dietary supplement industry. This article discusses relevant components of the DSHEA, explains the division of regulatory responsibilities between the FDA and the Federal Trade Commission (FTC), and refutes the often cited allegation that the herb and dietary supplement industry are unregulated.

Chemistry, Pharmaceutical↗
PubMedDate not supplied

[Enteral supplements: dietary supplements or substitutes?].

OBJECTIVE: To assess the use of oral nutritional supplements analyzing the reason for prescription and its implication in caloric-protein intake. SETTING: study performed at a university hospital of 350 beds with medical and surgical specialties. SUBJECTS, PATIENTS: Patients inclusion was done by selecting all starting oral nutritional supplement prescription. Exclusion criteria were being younger than 18 years, being admitted to the Intensive Care Unit, having cognition or communication impairments, being on concomitant parenteral nutrition or requiring complete enteral diet, and/or using nasogastric tube for feeding. We also excluded special enteral diets, specifically designed for certain conditions. INTERVENTIONS: One-year long prospective study on prescription of oral nutritional supplements. Through clinical chart review and personal interview, we recorded demographic data, nutritional parameters, characteristics of the diet and supplement, and caloricprotein intake prescribed and ingested. The data were introduced in an Access97 database and processed by means of SPSS software for Windows. We performed a descriptive study of quantitative and qualitative variables, a chi2 analysis between qualitative variables, and a comparative analysis between means of all paired data by means of the student's t test, and variance analysis between quantitative variables. The significance level was set at p < 0.05. RESULTS: we were only able to analyze 77 out of 130 prescriptions for nutritional supplements since we could not adequately interview the remaining patients, mainly due to neurological impairments. Mean age was 74.8 years (SD = 12) and 50.6% were women. The departments prescribing the highest number of supplements were hematology (22.1%) and internal medicine (20.8%). GI neoplasm was the most frequent diagnosis at admission (27.3%). The most frequent indication was kwashiorkor (45.5%), with 15.6% of patients being well nourished. Mean therapy duration was 11 days (SD = 11.1), and the main reason for termination was hospital discharge (70.1%). The supplement was concomitantly prescribed with the meals in 70.6% of the cases, and more than half of the patients (70.1%) liked it, the most frequently prescribed was as a cream (61%) and the best accepted being as a liquid (78%). The average daily caloric load ingested with the foods of the hospital diet was similar between the first an third days of supplement prescription (p = 0.879) and the first and seventh days (p = 0.499). So happened when analyzing protein intake. With the supplement administration, there was a significant increase in patients' caloric intake from 310 Kcal at the third day to 337 Kcal at the seventh day (p < 0.0005) in both cases. Similar results were obtained when assessing total protein load ingested (p < 0.0005). CONCLUSIONS: Nutritional supplements are correctly used in most of the cases. They allow for a significant increase in the protein-caloric intake with no modification of hospital diet, becoming an appropriate nutritional source when the diet is insufficient.

Aged↗
PubMed2002

[Influence of bioactive dietary supplement--dietary unsaturated fats--on immune status of patients with myocardial ischemia and impaired glucose tolerance].

Immune status measured by the flow cytrometric analysis under the ischemic heart disease and IHD with impaired glucose tolerance has been found to be altered in B cells as well as in T lymphocytes in some cases. Having received the diet supplemented by PUFA "Eicolen", IHD patients present with the restored immune status. Patients with IHD and impaired glucose tolerance did not present with any significant modifications in immune status after PUFA "Eicolen" supplementation.

Aged↗
PubMed2004

[Doping and dietary supplements].

Dietary supplements are widely promoted and used all over the world as a means of losing weight, increasing energy and athletic performance, or for compensating for true or supposed deficits. Traditionally, dietary supplements have been defined as products composed of one or more essential nutrients such as vitamins, minerals, and protein. But, in 1994, the US Congress broadened the definition to include (albeit with some exceptions) any product intended for ingestion as a supplement to the diet. This includes vitamins, minerals, herbs, botanicals, and other plant-derived substances; amino acids and substances such as enzymes, hormones, and metabolites. Some dietary supplements contains substances prohibited by anti-doping rules or may pose a health risk to some persons. Positive cases of doping can be found in three cases: amphetamine-like compounds that have potentially powerful stimulant effects on the nervous system and heart; hormones and pro-hormones; and intentional contamination of dietary supplements with hormones (mainly anabolic steroids). French and EU laws protect French consumers from adverse events related to the use of these products. Nevertheless, lack of controls in some European countries, Internet sales, and poor knowledge among some health care professionals create a persistent risk of use of fake products.

Central Nervous System Stimulants↗
PubMed2004

Concentrations of ephedra alkaloids and caffeine in commercial dietary supplements.

Dietary supplements that contain Ma Huang (ephedra alkaloids) and guarana (caffeine) are widely marketed and used in the U.S. for weight loss and athletic performance enhancement, despite a lack of adequate research on the pharmacology of these botanical stimulants. We developed and applied a novel liquid chromatography-tandem mass spectrometry (LC-MS-MS) method to quantitate the various ephedra alkaloids found in dietary supplements that contain Ephedra species. The quantities of ephedrine, pseudoephedrine, norephedrine, norpseudoephedrine, methylephedine, methylpseudoephedrine, and caffeine were determined for 35 commercial dietary supplements and compared with the amounts listed on the product labels. The total ephedra alkaloid content ranged from 5.97 mg to 29.3 mg per serving. Two supplement brands did not list the quantity of ephedra alkaloids on the label, and four did not list the amount of caffeine per serving. Of the products tested, 31% contained > 110% of the total ephedra alkaloids listed on the label, and 6% of the supplements contained < 90% of the listed amount. For caffeine, 86% of the product lots that listed the caffeine amount contained less than 90% of the labeled quantity. No products contained > 110% of the declared caffeine content. The total ephedra alkaloid content varied significantly from lot to lot in 5 of 9 products. Three product brands contained proportions of alkaloids that exceeded amounts reported for E. sinica, including one that was 98% ephedrine, one that had 10% norpseudoephedrine, and one that contained an average of 13% methylephedrine. We conclude that product inconsistency is common among some commercially available dietary supplements that contain ephedra alkaloids and caffeine.

Alkaloids↗
PubMed2000

Regulatory and ethical issues with dietary supplements.

Dietary supplements are commonly used, and many are effective or hold promise for treating various conditions. However, they do not require Food and Drug Administration (FDA) approval. Impurities and adulterants have been found in the products, mostly due to the lack of requirements for good manufacturing practices. In addition, as no standardization is required, the active ingredient may be absent or highly variable among manufacturers. The FDA published its 10-year plan for dietary supplements that addresses safety, labeling, boundaries, enforcement, research, and outreach. This endeavor, if put into place, will be instrumental in providing consumers with more confidence in the safety, composition, and labeling of dietary supplements.

Advertising↗
PubMed1991

The bleeding time effects of a single dose of aspirin in subjects receiving omega-3 fatty acid dietary supplementation.

Dietary supplementation with omega-3 fatty acids reduces platelet aggregation in subjects who usually eat a diet low in these fatty acids. Aspirin also has an antiplatelet effect. The clinical effects of the concomitant administration of these agents were examined in this double-blind controlled crossover trial. Twelve healthy adults were randomized to supplement their diet for 21 days with 8 g of omega-3 fatty acids or identical-looking olive oil capsules. At the end of each treatment period, bleeding times were obtained before and after the administration of one 325-mg aspirin tablet. Overall, percent change in bleeding time after omega-3 fatty acid supplementation was significantly prolonged compared with olive oil supplementation before aspirin administration but not after. Bleeding times were influenced significantly by the order of randomization in the two treatment groups. Changes in post-aspirin bleeding time varied in subjects after they received olive oil. Post-aspirin bleeding times after omega-3 fatty acid supplementation were prolonged compared with baseline values but not significantly prolonged when compared with those after olive oil administration. The authors concluded that the concomitant administration of a single dose of aspirin does not prolong bleeding time in subjects who eat a diet enriched by omega-3 fatty acids versus a diet enriched by olive oil.

Aspirin↗
PubMed2005

Computer access to research on dietary supplements: a database of federally funded dietary supplement research.

Dietary supplement use is prevalent in the United States, but support for supplement research has been relatively modest and only recently emphasized at the NIH. The Dietary Supplement Health and Education Act of 1994 led to the creation of the Office of Dietary Supplements (ODS) at the NIH to promote research on dietary supplements. In order to track federally funded dietary supplement research, the ODS developed a database known as Computer Access to Research on Dietary Supplements (CARDS). This article provides an overview of the development and potential uses of the CARDS database. In addition, we report that NIH-funded dietary supplement research steadily increased from fiscal year (FY) 1999 through 2002. The majority of NIH institutes or centers (ICs) funded research relevant to dietary supplements during this time, led by the National Cancer Institute and one of the newest NIH ICs, the National Center for Complementary and Alternative Medicine. CARDS data indicate that NIH-funded dietary supplement research from FY 1999 through 2002 involved primarily vitamins, minerals, botanicals and phytochemicals. Cancer and cardiovascular disease, two of the leading causes of morbidity and mortality in the United States, collectively accounted for almost 45% of the research related to dietary supplements. A variety of types of research studies were funded, with the majority consisting of human intervention studies. This information is useful to evaluate trends in federally funded dietary supplement research, identify research gaps, and help research scientists identify potential sources of NIH funding.

Complementary Therapies↗
PubMed1984

Australian dietary supplementation practices. Health and dietary supplements.

A random mail survey of 726 adults living in the Adelaide metropolitan area was carried out to determine the prevalence of dietary supplementation and its relationship to health. In the month before the survey, 37% of men and 53% of women had taken some form of supplement. The most popular supplements were bran, multivitamins, B-complex vitamins, vitamin C and wheatgerm. Most supplementation was used regularly (daily or almost daily) and over a prolonged period. Although the subjects who took supplements did not use medical facilities more often than those who took none, they reported having more bouts of minor illness in the preceding year. They also reported the more frequent occurrence of minor symptoms, and took more unprescribed medications than did those who did not use dietary supplements.

Australia↗
PubMed2006

Proposed rule: current good manufacturing practice in manufacturing, packing, or holding dietary ingredients and dietary supplements.

The Dietary Supplement Health and Education Act (DSHEA) was enacted in October 1994 to promote the health of Americans by ensuring easier access to safe dietary supplements. Many supplements such as vitamins, minerals, herbs and amino acids have been reported to be helpful in chronic conditions (i.e., heart disease, cancer and osteoporosis). Under DSHEA, dietary supplements can be marketed without prior FDA approval; the burden is on this agency to show that a marketed dietary supplement is unsafe. However, DSHEA retained the FDA's authority to issue regulations that require the manufacture of dietary supplements be in compliance with current good manufacturing practice (cGMP) standards, which are needed to ensure their quality. Several quality-related concerns of marketed dietary supplements that came to light since the passage of DSHEA prompted the FDA in 2003 to propose rules for cGMP for the manufacture, packaging and holding (storage) of dietary supplements. This review will present the highlights of these proposed rules, focusing on the legislative history of DSHEA, rationale for proposing cGMPs along with a general discussion of the specific requirements. Given the voluminous nature of the specific details, the reader is directed to the pertinent FDA publications for details. In this analysis, selected scientific and legal issues are also discussed to promote a better understanding and implications of these rules.

Dietary Supplements↗
PubMed2006

Dietary supplement use among health care professionals enrolled in an online curriculum on herbs and dietary supplements.

BACKGROUND: Although many health care professionals (HCPs) in the United States have been educated about and recommend dietary supplements, little is known about their personal use of dietary supplements and factors associated with their use. METHODS: We surveyed HCPs at the point of their enrollment in an on-line course about dietary supplements between September, 2004 and May, 2005. We used multivariable logistic regression to analyze demographic and practice factors associated with use of dietary supplements. RESULTS: Of the 1249 health care professionals surveyed, 81 % reported having used a vitamin, mineral, or other non-herbal dietary supplements in the last week. Use varied by profession with highest rates among nurses (88%), physician assistants or nurse practitioners (84 %) and the lowest rates among pharmacists (66%) and trainees (72%). The most frequently used supplements were multivitamins (60%), calcium (40%), vitamin B (31%), vitamin C (30%), and fish oil (24%). Factors associated with higher supplement use were older age, female, high knowledge of dietary supplements, and discussing dietary supplements with patients. In our adjusted model, nurses were more likely than other professionals to use a multivitamin and students were more likely to use calcium. CONCLUSION: Among HCPs enrolled in an on-line course about dietary supplements, women, older clinicians, those with higher knowledge and those who talk with patients about dietary supplements had higher use of dietary supplements. Additional research is necessary to understand the impact of professionals' personal use of dietary supplements on communication with patients about them.

Adult↗
PubMed2000

Effects of sesamin-supplemented dietary fat emulsions on the ex vivo production of lipopolysaccharide-induced prostanoids and tumor necrosis factor alpha in rats.

BACKGROUND: Sesamin, a nonfat constituent of sesame oil, inhibits Delta(5)-desaturase activity, resulting in accumulation of dihomo-gamma-linolenic acid (DGLA), which displaces arachidonic acid (AA) and consequently decreases the formation of proinflammatory 2-series prostaglandins. OBJECTIVE: We sought to determine whether dietary supplementation with sesamin augments the antiinflammatory effects of dietary linseed oil in rats. DESIGN: We investigated the effects of continuous tube feedings of emulsions containing safflower oil or linseed oil with sesamin (SO+ and LO+) or without sesamin (SO and LO) on liver fatty acid composition and on endotoxin-induced production of prostaglandin E(2), 6-keto-prostaglandin F(1alpha), and tumor necrosis factor alpha (TNF-alpha) by whole blood from rats (n = 6 per diet group). RESULTS: We found a significant accumulation of DGLA only in the liver phospholipids of animals fed SO+ and LO+ (1.8 +/- 0.2 and 1.4 +/- 0.3 mol%, respectively), which suggests that sesamin inhibited Delta(5)-desaturation of n-6 fatty acids. These changes were associated with significant reductions in plasma prostaglandin E(2) concentrations in animals fed SO+ compared with those fed SO (P: < 0. 05). Despite a significant reduction in tissue AA content in the LO group, the prostaglandin E(2) concentrations did not differ significantly from those of the SO group. Plasma concentrations of TNF-alpha were significantly lower (P: < 0.05) in the animals fed LO+ than in those fed SO (199 +/- 48 and 488 +/- 121 ng/L, respectively). CONCLUSION: These data indicate that in rats, tube feedings of diets containing sesamin exerted antiinflammatory effects that were augmented by concurrent consumption of linseed oil.

6-Ketoprostaglandin F1 alpha↗
PubMed1991

K-ras mutations in 1,2-dimethylhydrazine-induced colonic tumors: effects of supplemental dietary calcium and vitamin D deficiency.

Recent studies from our laboratory have demonstrated that dietary supplemental calcium had no significant effect on the incidence of 1,2-dimethylhydrazine-induced colonic tumors, but did decrease the number of rats with multiple tumors and reduced tumor size. Moreover, concomitant vitamin D deficiency appeared to abolish these protective effects of calcium on colonic tumors in this experimental model. To date, however, the mechanism(s) involved in these phenomena remain unclear. In order to address these important issues, 1,2-dimethylhydrazine-induced colonic tumors from animals on control, Ca(2+)-supplemented, vitamin D-sufficient, and Ca(2+)-supplemented, vitamin D-deficient diets were examined for the presence of ras oncogene mutations. DNA was extracted from each of these tumors. Targeted areas of K-ras and H-ras genes were amplified by the polymerase chain reaction and analyzed for point mutations using allele-specific oligonucleotide hybridization and subsequent DNA sequencing. The results of these studies demonstrated that: (a) approximately one-third of 1,2-dimethylhydrazine-induced colonic carcinomas in the control group had K-ras G to A mutations; (b) no mutations, however, were detected in the cancers of the calcium-supplemented group; (c) concomitant vitamin D deficiency abolished the antimutagenic effect of dietary calcium supplementation (e.g., approximately one-third of cancers in this group again had detectable K-ras mutations); and (d) no H-ras point mutations were detected in colonic tumors from any group. These findings suggest that alterations in K-ras mutations may be one possible mechanism by which calcium and vitamin D status influence colonic carcinogenesis in this experimental model.

1,2-Dimethylhydrazine↗
PubMed2005

Effects of different levels of dietary supplemental selenium on performance, lipid oxidation, and color stability of broiler chicks.

This study examined the effects of supplemental dietary selenium on growth performance, lipid oxidation, and color stability of broiler chicks. Male broiler chicks (Arbor Acres, 1 d old, total 900 chicks) were randomly assigned to 6 pens containing 30 chicks each, corresponding to each of 6 dietary treatments. Six different diets were supplied to the chicks from 3 to 6 wk of age. After 42 d of feeding, all the broilers were slaughtered conventionally at a slaughtering plant. The carcasses were packed in polyethylene bags in a manner similar to that used for retail trade and stored for 12 d at 4 degrees C. Body weight and feed efficiency were not affected by dietary selenium levels, and no adverse effect on growth was observed during the experimental period. The dietary selenium and alpha-tocopherol levels did not affect surface meat color or level of metmyoglobin accumulation. Lipid stability was improved by supplementation with 100 IU of alpha-tocopherol (P < 0.05). Dietary selenium supplementation at 8 ppm in combination with 100 IU of alpha-tocopherol, however, was more effective in reducing lipid oxidation compared with 100 IU of alpha-tocopherol/kg feed only (P < 0.05). Supplementation with 100 IU of alpha-tocopherol affected cholesterol oxidation product levels on d 7 and 12, but selenium supplementation did not have an additional effect on the reduction of cholesterol oxidation products. Therefore, an increase in the dietary selenium from 1 to 8 ppm revealed only minor improvements in the oxidative stability of chicken meat during refrigerated storage.

Animals↗
PubMed2001

Digoxin toxicity in a 26-year-old woman taking a herbal dietary supplement.

Herbal dietary supplements are often considered by patients to be safe and free from side effects. The case described here shows digoxin toxicity in a patient taking a dietary supplement not normally considered to contain digoxin. In addition to highlighting the risks of herbal supplements, this case also demonstrates the concept that digoxin equivalents are not picked up by the standard digoxin assay.

Adult↗
PubMed2005

Simultaneous determination of synthetic phosphodiesterase-5 inhibitors found in a dietary supplement and pre-mixed bulk powders for dietary supplements using high-performance liquid chromatography with diode array detection and liquid chromatography-electrospray ionization tandem mass spectrometry.

A high-performance liquid chromatography-diode array detection (HPLC-DAD) method and a liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) method were developed to screen for the presence of synthetic phosphodiesterase-5 (PDE-5) inhibitors and their analogues, namely sildenafil, vardenafil, tadalafil, homosildenafil, acetildenafil and hydroxyhomosildenafil. The methods were applied to pre-market samples submitted to the Health Sciences Authority of Singapore (HSA) for testing. One sample was in the form of capsules while six other samples were pre-mixed bulk powder samples for dietary supplements to be repackaged or formulated into the final dosage forms (usually capsules). Identification of PDE-5 inhibitors and their analogues was achieved by comparing individual peak retention times, UV spectra and mass spectra with those of reference standards. The seven samples were found to contain at least one of the following compounds: sildenafil, vardenafil, hydroxyhomosildenafil, homosildenafil and acetildenafil. The five compounds were simultaneously determined by LC-ESI-MS/MS in multiple reactions monitoring (MRM) scan mode. The method has been validated for accuracy, precision, linearity and sensitivity.

3',5'-Cyclic-GMP Phosphodiesterases↗