Over the last decade, the FDA has recalled hundreds of dietary supplements that have been linked to serious (and even fatal) side effects. Part of the reason these dangerous products continue to make it to market is that they aren't considered foods or drugs, meaning they come with their own set of rules. The agency can institute warnings, bans, and recalls after consumers report problems, but it must rely on manufacturers to operate aboveboard and report new ingredients. There are supplements that have been proven to be safe and effective. These are not those supplements.