The Government Accountability Office (GAO) says the FDA should take actions to improve their regulation of dietary supplements. Although FDA has taken limited steps to identify and act on safety concerns, a number of factors may allow potentially dangerous products on the market. FDA dedicates relatively few resources to dietary supplement oversight, In addition, FDA ability to remove dietary supplements from the marketplace is hindered because the agency carries the burden proving significant or unreasonable risk. (With food additives and drugs, the manufacturer has the burden of proving safety before marketing).
Anyone who has read my book will find this report to be old news. However, the report offers a well written summary of the situation, and the appendices contain interesting information on FDA actions and a comparison chart on foreign country regulation of dietary supplements.