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pieter cohen

The ‘natural’ pill myth


Last month, the Food and Drug Administration warned 10 companies that they were inappropriately marketing dietary supplements containing a hazardous new ingredient: 1,3-dimethylamylamine, or DMAA. This might appear at first glance to be evidence of the FDA protecting the public from rogue elements in the supplement industry. In fact, this “new” ingredient has been heavily promoted since 2007 at major retail chains, including GNC and Vitamin Shoppe, as the FDA watched silently. Instead of reassuring us of the safety of supplements, the FDA’s action reveals that lax regulation, industry ingenuity, and FDA passivity have created a hazardous marketplace in which the distinction between supplements and medications has become hopelessly blurred.

Americans spend $28 billion a year on vitamins, minerals, herbals, probiotics, and other dietary supplements assuming they are safe. Herbal supplements are often sold with blossoming flowers and verdant leaves on the packaging implying that the ingredients in the pills and powders are natural extracts of the featured plant. They may not be. In fact, untested synthetic compounds — no different than medications — often masquerade as natural supplements.


The FDA’s recent warnings address only the most blatant example of a pharmaceutical compound posing as a natural supplement, and even this action likely would not have occurred had it not been for the work of astute military scientists and physicians. Two years ago, military toxicologists noticed an unexplained spike in the number of troops with positive amphetamine urine tests, and the toxicologists’ research led them to a surprising discovery: The positive tests were due to an amphetamine-like drug called DMAA. Withdrawn by Eli Lilly & Co. over 40 years ago, DMAA was now purchased by troops as supplements at GNC stores at military exchanges worldwide.

Shortly after the scientists’ discovery, two soldiers participating in military exercises died unexpectedly. The soldiers had been using supplements with DMAA, which is suspected to have caused strokes and heart failure at high dosages, and military physicians suspected DMAA had played a role in the soldiers’ deaths as well. The military promptly removed DMAA supplements from military exchanges, but two unsettling questions remain: How did the medication DMAA come to be sold in supplements in the first place; and, why is it still sold to civilians at countless stores throughout the United States?


The answer to why DMAA appeared in supplements is straightforward: Any botanical ingredient that has a documented history of use in food or supplements before 1994 is, according to the current law, assumed to be safe. Manufacturers claim that DMAA is found in rose-scented geranium, which has been used for decades to add subtle flavor to jams and teas. Therefore, DMAA is assumed to be safe, even though it is synthetically produced in a factory and concentrated at much higher levels than previously consumed in food.

The fact that such skimpy evidence qualifies high-dose DMAA as safe for over-the-counter sale may be worrisome to many consumers. Unfortunately, the problem may run deeper. It turns out that manufacturers have relied on just one study published in the now-defunct Chinese language Journal of the Guizhou Institute of Technology to support the claim that DMAA is found in geranium. The researchers performed no confirmatory tests in that study, and since its publication over a half-dozen independent scientific teams have been unable to confirm the finding.


Over the past six years, almost a half billion dosages of DMAA have been sold at GNC stores alone. GNC’s chief executive officer Joe Fortunato reported on a February conference call with investors that “from a perspective of sales, we’ve seen no impact whatsoever” from the military recall. From my clinical perspective I can say the same: Patients continue to arrive at my clinic consuming DMAA supplements and suffering the consequences.

The reasons for the FDA’s dithering on DMAA are unclear. Possibly, the agency was hoping to find a compromise with the supplement industry. Last year the FDA proposed a draft guidance on new supplement ingredients that explicitly permits synthetically produced botanical ingredients as long as evidence exists to support a “reasonable expectation of safety.” Far from embracing this compromise, industry advocates have assailed the proposal and have mounted a lobbying effort pressuring the FDA to withdraw it. However, even implementing this controversial draft guidance would have only modest impact.

The real policy fix requires Congress to revise the law such that synthetically produced botanical ingredients are not permitted in dietary supplements, effectively creating a clear distinction between supplements and medications. This would ensure unhindered access for American consumers to vitamins, minerals, and natural herbal extracts while eliminating untested synthetic substances. Without such a fix, consumers will continue to have a false sense of security every time they open a bottle of “natural” supplements.

Pieter Cohen is an assistant professor at Harvard Medical School and an internist at Cambridge Health Alliance.