The FDA is the federal agency that oversees dietary supplements in the United States. Unlike prescription and over-the-counter medications, which must be approved by the FDA before they can be placed on the market, dietary supplements do not require review or authorization by the FDA prior to going to market. In addition, manufacturers do not have to provide evidence to the FDA that their products are safe or effective before selling them.
When the FDA finds a dietary supplement that is not safe, you can take it out of the market or ask the supplement manufacturer to remove it. The FDA and the Federal Trade Commission can also take action against companies that make false claims in supplements about weight loss; that add drugs to supplements; or that indicate that supplements can diagnose, treat, cure or prevent a disease.