Dietary supplements: how they are used and regulated.

Overall use of nutrient and botanical dietary supplements (DS) has increased for years across all major categories. Many DS are simply taken as part of a healthy lifestyle, but some are used to reduce risk of or modulate risk factors for specific chronic diseases, such as heart disease (vitamin E, folic acid, garlic), cancer (selenium, vitamin E, garlic) and certain birth defects (folic acid). Other DS are used for short-term benefits such as sleep management (valerian, melatonin) and enhanced physical performance (pyruvate, creatine). DS are regulated under food law, but with certain provisions that apply only to DS. Thus, DS are eligible for Food and Drug Administration (FDA)-authorized health claims under the Nutrition and Labeling Education Act (NLEA). Health claims have already been authorized for folic acid and calcium, but not for several others. In 1994, when the Dietary Supplement Health and Education Act (DSHEA) was passed, it expanded and clarified the definition of DS, specified additional requirements for safety and provided for four types of claims of nutritional support. These include prevention of classic nutritional deficiencies, structure or function (S/F) effects, mechanisms for S/F effects and general well-being. Although S/F effects result from both foods and drugs, representation that a product will treat, cure, mitigate or diagnose a disease is reserved for drugs. Therefore, the wording of S/F claims for DS has become a difficult issue in the proposed DS labeling regulations.