Defined by law as a vitamin, mineral, herb, botanical, an amino acid, a dietary substance added to supplement the diet to increase the total dietary intake, or concentrate, metabolite, constituent, extract or combination of any ingredients described above. Supplements cannot be represented for use as a conventional food or sole item of a meal or the diet; and they must be labeled as dietary supplements. Regulatory authority rests with the Food and Drug Administration. There are concerns about the degree of regulation by FDA for safety and claims made for the products by manufacturers.