Congress defined the term "dietary supplement" in the Dietary Supplement Health and Education Act (DSHEA). A dietary supplement is a product taken by mouth that contains a "dietary ingredient" intended to supplement the diet.
The "dietary ingredients" in these products may include: vitamins, minerals, herbs or other botanicals, amino acids, and substances such as enzymes, organ tissues, glandulars, and metabolites.
Dietary supplements can also be extracts or concentrates, and may be found in many forms such as tablets, capsules, softgels, gelcaps, liquids, or powders. They can also be in other forms, such as a bar. Whatever their form may be, DSHEA law places dietary supplements in a special category under the general umbrella of "foods," not drugs, and requires that every supplement be labeled a dietary supplement.
Under DSHEA, a firm is responsible for determining that the dietary supplements it manufactures or distributes are safe and that any representations or claims made about them are substantiated by adequate evidence to show that they are not false or misleading. This means that dietary supplements do not need approval from the Food and Drug Administration before they are marketed. Except in the case of a new dietary ingredient, where pre-market review for safety data and other information is required by law, a firm does not have to provide the FDA with the evidence it relies on to substantiate safety or effectiveness before or after it markets its products.
Manufacturers and distributors do not need FDA approval to sell their dietary supplements. This means that FDA does not keep a list of manufacturers, distributors or the dietary supplement products they sell. If you want more detailed information than the label tells you about a specific product, you may contact the manufacturer of that brand directly. The name and address of the manufacturer or distributor can be found on the label of the dietary supplement.
Some supplements may interact with prescription and over-the-counter (OTC) medicines. Taking a combination of supplements or using these products together with medications (whether prescription or OTC drugs) could under certain circumstances produce adverse effects, some of which could be life-threatening. Be alert to advisories about these products, whether taken alone or in combination.
For example: Coumadin (a prescription medicine), ginkgo biloba (an herbal supplement), aspirin (an OTC drug) and vitamin E (a vitamin supplement) can each thin the blood, and taking any of these products together can increase the potential for internal bleeding. Combining St. John's Wort with certain HIV drugs significantly reduces their effectiveness. St. John's Wort may also reduce the effectiveness of prescription drugs for heart disease, depression, seizures, certain cancers or oral contraceptives.