FDA Warnings Have Little Effect on Adulterated Nutritional Supplements

U.S. nutritional supplement sales total about US$30 billion annually and are largely unregulated. The FDA is prohibited by law from evaluating supplements for safety or efficacy prior to marketing but can issue postmarketing warnings if adulterants are found. Two studies demonstrate that these FDA warnings are ineffective.

In the first study, researchers used an FDA database to identify 776 supplements that were investigated and found to be adulterated based on adverse events or consumer complaints from 2007 to 2016. Nearly all supplements were marketed for sexual enhancement, weight loss, or muscle building. The most common adulterants in these three categories were sildenafil (or its analogs), sibutramine, and anabolic steroids or steroid-…