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A multivitamin is a preparation intended to be a dietary supplement with vitamins, dietary minerals, and other nutritional elements. Such preparations are available in the form of tablets, capsules, pastilles, powders, liquids, and injectable formulations. Other than injectable formulations, which are only available and administered under medical supervision, multivitamins are recognized by the Codex Alimentarius Commission (the United Nations' authority on food standards) as a category of food.〔(Codex Guidelines for Vitamin and Mineral Food Supplements ) Accessed 27 December 2007〕 Multivitamin supplements are commonly provided in combination with dietary minerals. A multivitamin/mineral supplement is defined in the United States as a supplement containing 3 or more vitamins and minerals that does not include herbs, hormones, or drugs, where each vitamin and mineral is included at a dose below the tolerable upper level, as determined by the Food and Drug Board, and does not present a risk of adverse health effects.〔National Institutes of Health State-of-the-Science Panel. National Institutes of Health State-of-the-Science Conference Statement: multivitamin/mineral supplements and chronic disease prevention" ''Am J Clin Nutr'' 2007;85:257S-64S〕 The terms multivitamin and multimineral are often used interchangeably. There is no scientific definition for either.〔() Accessed 21 July 2009〕 In otherwise healthy people, some scientific evidence indicates that multivitamin supplements do not prevent cancer, heart disease, or other ailments. However, there may be specific groups of people who may benefit from multivitamin supplements (for example, people with poor nutrition or at high risk of macular degeneration).〔〔 ==Products and components== Many multivitamins are formulated or labeled to differentiate consumer sectors, such as prenatal, children, mature or 50+, men's, women's, diabetic, or stress. Consumer multivitamin formulas are available as tablets, capsules, bulk powder, or liquid. Most multivitamins are intended to be taken once or twice per day, although some formulations are designed for consumption 3–7 or more times per day. Compositional variation amongst brands and lines allows substantial consumer choices. Modern multivitamin products roughly classify into RDA (recommended dietary allowance) centric multivitamins with or without iron, RDA centric multivitamin/multimineral formulas with or without iron, higher potency formulas with mostly above RDA components with or without iron, and more specialized formulas by condition, such as for diabetics or by less common components, such as diversified antioxidants, herbal extracts, or premium vitamin and mineral forms. Legally, the United States Food and Drug Administration allows a multivitamin to be called "high potency" if at least two-thirds of its nutrients have at least 100 percent of the DV. In practice, "high potency" usually means substantially increased vitamins C and B, with some other enhanced vitamin and mineral levels, though some minerals may still be much less than DV. Some components are typically much lower than RDA amounts, often for cost reasons. For example, biotin, usually the most expensive vitamin component, at over $4000 per active pound, is typically added in at only 5%-30% of RDA in many one per day formulations. Biotin is required to be present at 100% of the value of the B-vitamins for them to be absorbed by the body. Any B-vitamins that cannot be absorbed due to a lack of biotin are eliminated by the body. Likewise, boron and magnesium are considered essential for the bioavailability and absorption of Vitamin D and calcium. Sometimes low content composition is for population subgroups, where the RDA would be inappropriate. Iron is needed in larger amounts by menstruating women, but some percentage of HFE variant gene bearing males are at risk for hemochromatosis. Normal dietary intakes also vary by population, indicating different levels of supplementation. Basic commercial multivitamin supplement products often contain the following ingredients: vitamin C, B1, B2, B3, B6, folic acid (B9), B12, B5 (pantothenate), H (biotin), A, E, D3, K1, potassium iodide, cupric (sulfate anhydrous, picolinate, sulfate monohydrate, trioxide), selenomethionine, borate(s), zinc, calcium, magnesium, chromium, manganese, molybdenum, betacarotene, and iron. Other formulas may include additional ingredients such as other carotenes (''e.g.'' lutein, lycopene), higher than RDA amounts of B, C or E vitamins including gamma-tocopherol, "near" B vitamins (inositol, choline, PABA), trimethylglycine (anhydrous betaine), betaine hydrochloride, vitamin K2 as menaquinone-7, lecithin, citrus bioflavinoids or nutrient forms variously described as more easily absorbed. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Multivitamin」の詳細全文を読む スポンサード リンク
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