A multivitamin is any preparation containing more than a single vitamin. Tablets and injectable forms (for example Vitaped and Hospira) are available. In common usage, "multivitamin" refers to tablets that contain various vitamins usually along with dietary minerals and, occasionally, herbal extracts. more...
By supplementing the diet with additional vitamins and minerals, multivitamins can be a valuable tool for those with dietary imbalances or different nutritional needs . People with dietary imbalances may include those on restrictive diets and those who can't or won't eat a nutritious diet. Pregnant women and elderly adults have different nutritional needs, and a multivitamin may be indicated by their physician.
While multivitamins can be a valuable tool to correct dietary imbalances, it is worth exercising basic caution before taking multivitamins, especially if any medical conditions exist. Pregnant women should generally consult their doctor before taking any multivitamins. Severe vitamin and mineral deficiencies require medical treatment and cannot be treated with over-the-counter multivitamins.
Multivitamins may be toxic if large doses of various vitamins or minerals are taken. In particular, these include vitamin A, vitamin D, vitamin B6, iron, and potassium. This list is not exhaustive. Additionally, various medical conditions and medications may adversely interact with multivitamins. For normal adults taking a multivitamin for general health purposes, it is recommended that a multivitamin should contain 100% DRI or less for each ingredient.
Regulations by governmental agencies
Because of their categorization as a dietary supplement by the United States Department of Agriculture, most multivitamins sold in the U.S. are not required to undergo the same rigorous testing procedures typical of pharmaceutical drugs.
However, some multivitamins contain very high doses of one or several vitamins or minerals and therefore require a prescription in the U.S. Since such drugs contain no new substances, they do not require the same testing as would be required by a New Drug Application, but were allowed on the market as drugs due to the FDA's Drug Efficacy Study Implementation program. See 36 Fed. Reg. 6843 (Apr. 9, 1971).
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