by Marion Nestle
May 28 2010

Dismal reports on dietary supplements

Dietary supplements are in trouble these days.  For one thing, it’s really hard to demonstrate that they do any good.  For another, these products are poorly regulated.  Some recent examples:

  • Gingko biloba supplements don’t improve cognitive function in the elderly.
  • St. Johns Wort supplements don’t improve irritable bowel syndrome.
  • Most supplements do not improve mortality, except maybe glucosamine and chondroitin sulfate which are associated with a slight unexplained improvement in this particular review.
  • Most supplements are contaminated with toxic heavy metals says a GAO report with one of this agency’s typically inimitable titles: Herbal Dietary Supplements: Examples of Deceptive or Questionable Marketing Practices and Potentially Questionable Advice.

The New York Times account of the GAO report quotes Steve Mister, president of the Council for Responsible Nutrition, the supplement industry trade association, unsurprised by this finding.  Heavy metals, he said, are routinely found in soil and plants: “I don’t think this should be of concern to consumers.”

Oh great.  Glad he thinks so.  I’d be happier if we had a bit more regulation of these products.