title: Multivitamin and multimineral dietary supplements: definitions, characterization, bioavailability, and drug interactions.
abstract: Although multivitamins, multiminerals, and similar terms (eg, multis or multiples) are commonly used, they have no standard scientific, regulatory, or marketplace definitions. Thus, multivitamins-multiminerals refers to products with widely varied compositions and characteristics. Multivitamin-multimineral composition databases use label values as surrogates for analyzed values. However, actual vitamin and mineral amounts often deviate from label values. Vitamin and mineral bioavailability for dietary supplements also lacks a standard scientific and regulatory definition and validated in vitro and animal models that accurately reflect human bioavailabilities. Systematic information on the bioavailability and bioequivalence of vitamins and minerals in marketed products and on potential drug interactions is scarce. Because of limited information on product characteristics, our ability to directly compare results across studies, estimate changes in usage patterns or intakes over time, and generalize from published results to marketed products is problematic.
authors.affiliation: Office of Dietary Supplements, National Institutes of Health, Bethesda, MD 20892-7517, USA. yetleye@od.nih.gov
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Yetley
mesh_terms: D001682:Biological Availability; D002908:Chronic Disease / Q000517:prevention & control*; D003257:Consumer Product Safety; D019587:Dietary Supplements / Q000009:adverse effects / Q000706:statistics & numerical data; D004347:Drug Interactions; D019317:Evidence-Based Medicine; D006801:Humans; D007880:Legislation, Drug; D008903:Minerals / Q000008:administration & dosage* / Q000009:adverse effects / Q000493:pharmacokinetics; D011322:Primary Prevention; D012307:Risk Factors; D014481:United States; D014815:Vitamins / Q000008:administration & dosage* / Q000009:adverse effects / Q000493:pharmacokinetics
chemical_list: D008903:Minerals; D014815:Vitamins