Dietary supplements are marketed for nutritional support and health promotion, as well as for a number of other uses, including weight loss and sports performance enhancement. These products come in pill, capsule, and liquid form, as well as in forms that may appear similar to conventional food or beverages. Dietary supplement use is common in the U.S. population; over one-half of U.S. adults over age 20 take dietary supplements. Surveys show that number has been increasing. Dietary supplement production has increased over time. The number of dietary supplements on the market rose from 4,000 in 1994 to approximately 55,000 in 2009. The industry recorded over $30 billion in sales in 2011. In 2010-2011, top-selling supplements included vitamins, herbs and botanicals, sports nutrition supplements, and "specialty" supplements which the industry defines as supplements such as glucosamine, probiotics, dehydroepiandrosterone (DHEA), and fish oil that do not fit into other supplement categories. This report outlines the authority of the Food and Drug Administration (FDA) to regulate dietary supplements and summarizes dietary supplement-specific regulations for new dietary ingredients (NDI), good manufacturing practices (GMP), labeling, and claims. The report also discusses adverse event reporting for dietary supplements and other means of ensuring consumer safety through enforcement of these authorities and regulations. Dietary supplement advertising, which is regulated by the Federal Trade Commission (FTC) in coordination with the FDA, is also discussed. Finally, the report concludes with a discussion of policy issues related to the manufacture, regulation, and use of dietary supplements, including the identification of dietary supplements, the role of dietary supplements in health and health care, and dietary supplement safety. The Food and Drug Administration, U.S. Department of Health and Human Services (HHS), regulates the processing, manufacture, and packaging of dietary supplements under the Federal Food, Drug, and Cosmetic Act (FFDCA) of 1938. Since passage of the FFDCA, the federal government has generally regulated dietary supplements as food. FDA's authority specifically in regard to dietary supplements has been amended by subsequent legislation; these authorities and their implementation and enforcement are discussed in this section. Under the FFDCA, the FDA regulates the processing, manufacture, and labeling of food products. The agency has the authority to deem food (and dietary supplements) misbranded (i.e., inaccurately labeled or presenting unapproved claims) and adulterated (i.e., containing ingredients that pose a significant or unreasonable risk of illness or injury). The law authorizes the FDA to recall food (and dietary supplements) under specified circumstances. Nutrition labeling requirements for food, including dietary supplements, were established under the Nutrition Labeling Education Act of 1990 (NLEA). However, the Dietary Supplement Act of 1992 instituted a one-year moratorium on the implementation of dietary supplement labeling under NLEA. Congress subsequently required the FDA to create dietary supplement-specific regulations for labeling under the Dietary Supplement Health and Education Act of 1994 (DSHEA). DSHEA made changes to FDA's authority that differentiated certain aspects of dietary supplement regulation from regulation of conventional foods, in regard to 1) new dietary ingredients (NDI), 2) good manufacturing practices (GMP), 3) labeling, and 4) certain health claims for dietary supplements. Additionally, DSHEA excluded dietary supplement ingredients from the definition of a food additive. The Public Health Security and Bioterrorism Preparedness and Response Act required registration of food (including dietary supplement) manufacturers, processors, and packers with the FDA. Subsequent legislation provided FDA with additional authorities. Under the Dietary Supplement and Non-Prescription Drug Consumer Protection Act, Congress added requirements for mandatory reporting of adverse events for dietary supplements. Most recently, the Food Safety Modernization Act (FSMA) provided the FDA with mandatory recall authority for adulterated food (including dietary supplements) and for food that does not provide adequate allergen labeling. Within the FDA, regulation of both food and dietary supplements falls within the purview of the Office of Foods, Center for Food Safety and Applied Nutrition (CFSAN). Information on CFSAN oversight of dietary supplements is summarized in the text box that follows. FDA has the authority to take enforcement action against misbranded (i.e., inaccurately labeled or presenting unapproved claims) and adulterated (i.e., containing ingredients that pose a significant or unreasonable risk of illness or injury) dietary supplements in the form of warning letters, product seizures, and mandatory recalls. It may also ban an ingredient through the rule-making process. Under the FFDCA, a dietary supplement is considered adulterated under specified circumstances related to the product's contents and manufacturing processes: if the dietary supplement or dietary ingredient presents a significant or unreasonable risk of illness or injury either (1) under conditions of use recommended or suggested in the product's labeling, or (2) under normal conditions of use, if none are set forth in the product's labeling; if the dietary supplement contains a NDI for which there is inadequate information as to whether or not it presents a significant or unreasonable risk of illness or injury; if the Secretary declares the dietary supplement or a dietary ingredient therein to pose an imminent hazard to public health or safety; or if the dietary supplement contains a dietary ingredient that renders it adulterated because it is a poisonous or deleterious substance rendering the product injurious to one's health. A dietary supplement is considered misbranded if it is inaccurately labeled or presents unapproved claims. Under current law, the burden of proof of misbranding or adulteration is on the agency, and this is specific to dietary supplements. Prior to DSHEA, there was no statutory definition of dietary supplements. As amended by DSHEA, the FFDCA defines a dietary supplement as a product (other than tobacco) that is not represented as a conventional food and is intended to supplement the diet; contains one or more of the following dietary ingredients: vitamins, minerals, herbs or other botanicals, amino acids, and other substances or their constituents; is intended to be taken by mouth as a pill, capsule, powder, tablet, or liquid; and is labeled on the front panel as being a dietary supplement. Dietary supplements are generally regulated as food under the FFDCA. As such, they are subject to fewer premarket regulations than other items within the FDA's regulatory purview, such as drugs and medical devices. Similar to food manufacturers, dietary supplement manufacturers must register with the FDA, follow current good manufacturing practices, and must abide by nutrition labeling and claims regulations. However, by law, some of these regulations are dietary supplement-specific. Unlike food manufacturers, dietary supplement manufacturers are required to report serious adverse events to the FDA. In contrast to drugs, dietary supplements and their ingredients are generally presumed safe; also unlike with drugs, the FDA does not have the authority to require safety and efficacy testing for dietary supplements before they enter the market. Although processors, manufacturers, and packers of dietary supplements are expected to adhere to FDA regulations when bringing a new product to market, there is no pre-market approval process for dietary supplements. However, prior to entering the market, the FDA must be notified of dietary supplements containing New Dietary Ingredients, and of dietary supplements containing certain claims. After a supplement is on the market, FDA has the authority to deem dietary supplements misbranded or adulterated if they are inaccurately labeled, contain unapproved NDI, or contain harmful ingredients, and may issue warnings or order a mandatory recall in certain circumstances. The following sections provide details on FDA's dietary supplement-specific authorities, regulations, and guidance on NDI, GMP, labeling (including packaging, inserts, and information at the point of sale), claims, and serious adverse event reporting. A NDI is defined as a dietary ingredient that was not marketed in the United States in a dietary supplement before October 15, 1994. Supplement ingredients sold in the United States before October 15, 1994 are presumed safe based on their history of use by humans and do not need to be reviewed for safety by the FDA. For these grandfathered dietary supplement ingredients, manufacturers are required to maintain records that document their use prior to October 15, 1994. As long as documentation of grandfathered status exists, a product may be marketed without any evidence of efficacy or safety of its ingredients. The manufacturer of a NDI marketed after that date must give 75 days' premarket notification to the FDA, and must provide a history of use or other evidence of safety when used under recommended conditions. Prior to enactment of DSHEA in 1994, manufacturers were not required by law to notify the FDA of dietary supplement ingredients. Congress created a requirement for manufacturers to notify the FDA of NDI in DSHEA. There is, however, no list of dietary supplement ingredients that were on the market prior to that date. FSMA, enacted in December 2010, contained a provision requiring the FDA to clarify the definition of a NDI and to explain the requirements for safety evaluation of a NDI within 180 days of enactment. The FDA published draft NDI guidance on July 5, 2011. The draft guidance generated controversy, with some manufacturers expressing concerns that the proposed guidance was burdensome and not in keeping with DSHEA. In response to those concerns, the FDA agreed in June 2012 to revise the guidance. FDA has not proposed a timeline for the revised guidance. For each NDI, manufacturers are required to submit notifications to the FDA, and the ingredient must either (1) have been present in the food supply as an article used for food in a form in which the food has not been chemically altered, or (2) be accompanied by evidence supporting a "reasonable expectation of safety" under the recommended conditions of use.