Dietary supplements’ safety regulation: too much or not enough?

A new proposal to toughen the Food and Drug Administration’s power to regulate dietary supplements has the makers of vitamins, minerals and botanical extracts up in arms. But an editorial in the New England Journal of Medicine says the drug-safety agency’s proposed new powers do not go nearly far enough.

To expand its current $28-billion-a-year market, the dietary supplements industry is widely devising and selling formulations that use “novel” products -- minerals, plants, or amino acids that appear newly promising, which have not circulated widely in the United States before, or which are offered in “mega-doses” much higher than have been customarily used in supplements. An industry that produced and marketed 4,000 distinct products in 1994, when the regulatory framework for dietary supplements was written into law, now markets about 55,000 products to Americans who believe them to be safe to take.

Since 1994, those selling “novel” products have been required to provide federal regulators with evidence supporting a product’s “reasonable expectation of safety.” In a New England Journal of Medicine “Perspective” article published this week, Dr. Pieter Cohen, assistant professor of Medicine at Harvard University, suggests that even that vague standard has gone unenforced by the FDA and likely ignored by manufacturers eager to bring their supplements to market.


But in an effort to keep up, the FDA last July laid out a new raft of rules for those marketing “novel” dietary supplements in the United States. The new rules aim to spell out how a “reasonable expectation of safety” should be established. In some cases, the agency would accept documentation of a supplement’s “historical use” outside the United States. For “mega-doses” that exceed commonly used levels of a given supplement, the agency wants to see evidence of safety from animal studies and from test-tube studies. (While trials using human subjects in testing a supplement’s long-term use are allowed, they’re not required).

These new requirements, writes Dr. Cohen, aren’t enough. The “historical use” of a product where no one is looking for possible ill effects is a standard too low to assure safety, he writes. He adds that supplement manufacturers are under no obligation to share unfavorable safety data on a product with the FDA, so long as they offer studies that show the product is safe. And for products with no history of common use -- or marketed at super-high doses, “not even single-dose tolerability studies in humans would be required” by the new rules.

“If the FDA succumbs to industry pressure, the public health consequences will be significant,” writes Cohen.