I have discussed the bizarre and ineffectual regulatory scheme for dietary supplements in detail previously. The stunningly misnamed Dietary Supplement Health and Education Act (DSHEA) basically exempts any product called a “supplement” from any meaningful regulation to ensure safety or truthfulness in advertising. Companies selling supplements aren’t supposed to make claims about their products without good scientific evidence, and they aren’t allowed to claim to treat any specific disease, only to support the body’s normal “structure and function.” And all such products are supposed to carry the Quack Miranda Warning, which basically says the FDA hasn’t evaluated the companies’ claims and can’t guarantee the product is safe or effective.
Unfortunately, compliance is totally voluntary with no oversight or enforcement mechanism. The FDA isn’t allowed to verify the truthfulness of any marketing claims before a product goes on the market, and the burden for showing a product is harmful after it available is so high it is almost impossible to stop the sale of anything marketed as a dietary supplement. The fox is the only one with a key to the henhouse.
The government has repeatedly found casual and widespread violation of even the very limited regulations that exist. The FDA has found serious safety and quality control lapses in dietary supplement manufacturing. The GAO has reported on deceptive marketing of herbal remedies. And now the Department of Health and Human Services Inspector General has issued a report confirming that the “structure and function” claims analyzed for 127 supplements failed to meet even the limited requirements of DSHEA. The report concluded:
Overall, substantiation documents for the sampled supplements were inconsistent with FDA guidance on competent and reliable scientific evidence. FDA could not readily determine whether manufacturers had submitted the required notification for their claims. Seven percent of the supplements lacked the required disclaimer, and 20 percent included prohibited disease claims on their labels. These results raise questions about the extent to which structure/function claims are truthful and not misleading.
The report illustrates both the toothlessness of the voluntary guidelines as well as the lack of real scientific evidence to support the kinds of claims supplement manufacturers routinely make. Only 66 out of 104 companies contacted even agreed to submit information to investigators supposedly substantiating the claims they made for their products. And the documents that were submitted did not justify any confidence in the claims these manufacturers make. A few telling details from the report:
In contrast to FDA guidance, most substantiation was not derived from human studies.
Of the 34 percent of substantiation documents that were human studies, none met all of FDA’s recommendations for competent and reliable evidence.
10 percent of the documents appeared to have no significance in supporting structure/function claims.
FDA guidance recommends that when determining whether a claim is substantiated, manufacturers should consider all available scientific evidence—both favorable and unfavorable—and present the evidence in context. Interviews with staff at the National Center for Complementary and Alternative Medicine at the National Institutes of Health indicated that a large body of science exists that contradicts existing structure/function claims. Yet, 96 percent of the human studies we received were favorable to the supplements’ claims, suggesting that manufacturers either have not considered the body of available scientific evidence, that there is a positive bias in the documents selected to substantiate their claims, or that no such contradictory evidence exists.
85 percent of the 557 human studies we reviewed were not randomized, double-blind, parallel group, placebo-controlled trials.
49 percent of the human studies were not based on populations similar to those that will be consuming the supplements.
Seven percent of supplements in our sample were missing the required disclaimer for structure/function claims
Overall, the evidence submitted to support claims made about the effect of these supplements were cherry-picked to appear more positive than the total body of evidence available, consisted largely of unreliable pre-clinical studies and a few poor-quality clinical trials, and often had nothing at all to do with the claims being made. And presuming that those companies willing to voluntarily submit their supporting evidence had, in fact, better evidence to offer than those companies who ignored the request, it is very likely that most structure and function claims are completely without any basis in science at all.
It never ceases to amaze me that people rail vociferously (and often with good reason) at the misdeeds of pharmaceutical companies and yet seem perfectly comfortable with allowing a multi-billion dollar herb and supplement industry monitor itself and make barely even token efforts to find out if their products are safe or do what they are being taken for. This report recommends that the FDA seek the statutory authority to verify structure/function claims, and that would be a good start, though it seems unlikely in the current political climate. What would make even more sense, and would be more likely to protect the public from unsafe and ineffective supplements and deceptive advertising, would be to scrap DSHEA and regulate all medical products by the same, science-based standards of evidence. Sadly, something that reasonable seems even less likely to be possible.