Field of Science

Deceptive marketing of dietary supplements

Without any fanfare, Congress held a hearing recently on how supplements are marketed to the elderly. The Government Accountability Office (GAO) conducted a study of 40 different herbal supplements, looking at what the supplements actually contained as well as how they were being sold, both in stores and online. Not surprisingly, the GAO found that companies have been making deceptive, inaccurate claims about many of the most popular supplements sold in the U.S. (I’m shocked, shocked!)

As reported in last week’s Journal of the American Medical Association, the report was requested by Senator Herb Kohl. The report states that some of the companies involved have been referred to the FDA and FTC for appropriate action. But for some mysterious reason, it fails to provide any specific information about who these snake-oil purveyors are. That’s right: not a single company or website is named. Why not?

Well, thanks to the Internet, I can name a few of them - keep reading.

1. Ginkgo biloba. The GAO report says:
"Product labeling states it `Effectively treats Alzheimer’s Disease, depression, impotence, memory … and more.'" Not true: “Several NIH studies have shown ginkgo to be ineffective at reducing the risk of Alzheimer’s, or otherwise enhancing memory.”
Who made this claim? Supplement marketer Zooscape, that's who. You can find their ginkgo biloba claim (which matches the GAO report verbatim) here. Not surprisingly, Mercola makes some of the same claims, and throws in a claim that ginkgo biloba treats breast cancer.

2. Ginseng. The GAO report says:
"Product labeling states that it possesses a `Powerful Anti-cancer Function' and can prevent diabetes, among other questionable claims."
Nope. The NIH states that there is no clear evidence to support the claim that ginseng can prevent cancer or cardiovascular diseases. As far as diabetes claims, the NIH recommends that patients should instead use more proven therapies.

Who made this claim? Several supplement sellers, including Green Cross, and, both selling the same product.

3. Garlic. The GAO report says:
"Product labeling states that `Hundreds of scientific studies have proven [this product] to be number one, working to enhance the body’s immune function, protect cells from free radical damage, and reduce cardiovascular risk factors, including issues with blood pressure, cholesterol …' "
Wrong again. According to the GAO report,
“While this herb may help with certain conditions, enhancement of the body’s immune function is not a recognized benefit…. Further, the seller does not disclose details about the `hundreds of scientific studies' cited in the product labeling.”
Who makes this claim? I found it reproduced verbatim at several natural foods stores, such as here and here. The product itself - called only "this product" by the GAO - is Kyolic Aged Garlic Extract, manufactured by Wakanaga Nutritional Supplements.

The GAO report describes many other cases of deceptive marketing, including bogus claims to treat Alzheimer’s disease. This is especially disturbing claim in light of the fact that the GAO study specifically looked at marketing to elderly customers, who might be desperate for any such treatment.

The GAO also found some highly toxic contaminents in most of the supplements, including lead, mercury, arsenic, and cadmium. Out of 40 supplements, 37 tested positive for trace amounts of lead, 32 contained mercury, 28 contained cadmium, 21 contained arsenic, and 18 contained residues from at least one pesticide. For example, ginseng extracts contained hexachlorobenzene, metalaxyl, pyrimethanil, azoxystrobin, and other pesticides. The FDA stated that 16 of the 40 supplements would be considered in violation of U.S. pesticide tolerances.

Nice! So what are these doing on the market? Well, unfortunately, the FDA cannot regulate dietary supplements, thanks to a bill passed in 1994 as a big sloppy wet kiss to the supplements industry. As the GAO report says: “Under DSHEA [Dietary Supplement Health and Education Act of 1994], dietary supplements are broadly presumed safe, and FDA does not have the authority to require them to be approved for safety and efficacy before they enter the market. But the FDA can step in if supplement retailers claim that their products can treat, prevent, or cure disease.

DSHEA is a disaster, as this latest report illustrates, and as Orac has discussed at length over at Respectful Insolence. It's time for some oversight of this snake-oil industry.


  1. Are supplements sold in europe unregulated too?

  2. Europe has tougher regulations on supplements than the U.S., and it has different rules for herbal supplements versus vitamins and minerals. However, I don't know if enforcement is any tougher there. One of the main regulatory laws is called the European Food Supplements Directive, but the supplements makers have been fighting it. For example, see

  3. Any comments about about Avandia?

  4. This is very useful information and certainly raises concerns but exactly how does DSHEA stop the FDA from enforcing pesticide standards, good manufacturing protocols and the DSHEA labeling guidelines? You are right that these findings are an issue but really i don't see DSHEA as the reason for it, instead a lax or underfunded regulatory agency. Could you better detail how it's not just the FDA doing a crappy job?

  5. Anon: two quick responses; first, the GAO said they have notified the FDA about the pesticides so that FDA could take "appropriate action". Presumably the FDA will now do something (but maybe not). Second, DSHEA prevents the FDA from regulating supplements for safety or efficacy, so it is not the FDA's fault - they are prevented by statute from doing anything. The FDA is far from perfect, but this is one case where we can't blame them.

  6. Not all supplements do what they say and some may even be dangerous. So I would say do research, ask questions, and read labels before considering a supplement.

  7. I have cured myself of three different kinds of cancer without medical advice. I can tell you for a fact that all scientific studies including double blind studies are very questionable. I used substances and procedures that were proven to have no medicinal value whatsoever. I am glad to be alive with zero medical bills and taking no medications or supplements. I am 57 years old and am very active. I have recently became a father this year. Keep an open mind.


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