A systematic review published in JAMA assessing evidence quality for 84 commonly used dietary supplements found that only 14 had strong evidence from multiple randomized controlled trials supporting their specific claimed health benefits. The evidence-supported group includes folate for neural tube defect prevention, vitamin D for bone health in deficient individuals, and omega-3 fatty acids for hypertriglyceridemia management.
The regulatory framework governing supplements has not changed materially since 1994 despite substantial growth in industry size and a significant expansion in the boldness of implied health claims. The FTC pursues egregiously deceptive advertising cases but lacks resources to systematically evaluate the thousands of structure-function claims that companies can legally make without pre-market proof of efficacy. Consumer financial losses from supplements without meaningful benefit are estimated at 40 billion dollars annually.
