In a highly followed litigation (CRN and NPA filed a number of amicus briefs), United States v. Bayer Corp (US District Court for New Jersey) the Department of Justice and the Federal Trade Commission sought an Order holding Bayer in contempt of Court alleging that Bayer had violated the terms of a consent decree that required that the company posses "competent and reliable scientific evidence to substantiate its dietary supplement claims". This is the general standard that FTC requires for substantiation of all dietary supplement claims (see FTC Dietary Supplement Business Guide).
Despite the popular mythology surrounding the “unregulated dietary supplement industry,” the reality is that both the U.S. Food and Drug Administration (FDA) and the Federal Trade Commission (FTC) have significant regulatory authority over the marketing of supplements. FDA’s primary jurisdiction covers product labels and labeling while FTC is focused on product advertising. There can be significant overlap between “labeling” and advertising, as the Federal Food Drug and Cosmetic Act considers labeling to be any material directly connected to the sale of any regulated product—including dietary supplements.