Earlier this month NY State Attorney General Eric Schneiderman accused GNC, Target, Walgreen’s, and Walmart of selling supplements that contained little, if any, of the herb they purported to contain. This has caused tremendous uproar among consumers, providers, the dietary supplements industry, and retailers alike. The stores, in response, have pulled the products from their shelves. American consumers have been portrayed as stupid and gullible for using worthless and ineffective products. But what if the results of the tests aren't credible?
The attorney general used a relatively new method of testing for the presence of herbs called DNA bar coding, but DNA testing isn't particularly useful with herbal extracts, because little to no DNA remains after the commercial extraction process. Dr. Pieter Cohen, an assistant professor at Harvard and an expert on dietary supplements, told the New York Times that the test results were so extreme they were difficult to accept.
The World Health Organization and other government and non-profit organizations, such as US Pharmacopeia, European Pharmacopoeia, and American Herbal Pharmacopeia, have published extensively on which methods are best for ensuring the quality of botanical materials. They describe good agricultural and collection practices, methods for identifying contaminants and adulterants, and procedures for ensuring that the herbs contained within products are accurately identified. The American Botanical Council, a leading nonprofit herb education and research organization, criticized Schneiderman's actions in a press release as “premature,” and called out the use of DNA bar coding as a “useful but limited technology.”
As an integrative physician and teacher, I frequently prescribe supplements to my patients. Many dietary supplements are safer and more effective than their pharmaceutical alternatives. For example, I sometimes recommend DGL (deglycyrrhizinated licorice) for heartburn. It is a safe supplement with rare side effects, and it may eliminate the need for proton pump inhibitors (like Prilosec), which can cause iron deficiency anemia, community acquired pneumonia, and hip fractures. Another example is inositol for anxiety instead of benzodiazepines (like Xanax), which are addictive, hard to discontinue, and are associated with falls in the elderly.
Of course, if a dietary supplement doesn't contain the promised botanical, its purported benefit is moot. And it is true that the supplement industry has been fraught with poor products, especially those marketed for sexual enhancement, weight loss, and body building. At the same time, products have generally been improving. Since 2010 all companies are required by the FDA to follow good manufacturing practices, which identify the strength, quality, and purity of supplements.
Ideally, our government would set up a branch of the FDA that oversaw supplements. That's what Canada has done, and we could learn a lot from them: all supplement companies must apply and register their products; they don't allow grandfathering of products (which we do); products must be labeled with their use as opposed to our confusing structure/function claims (such as “supports bladder health.”)
Also in Canada, manufacturers can put a mandatory caution label on the products, which we do not allow. This would help when patients are on a medication like the blood thinner Coumadin, which interacts with some herbs and could cause harm. It would also be of great value to include the effective dose and education about popular uses – neither of which the U.S. currently allows.
At the University of Arizona Center for Integrative Medicine, where I serve as executive director, we teach thousands of residents and fellows each year how to recognize good supplement products. We recommend looking for the US Pharmacopeia or National Sanitation Foundation labels and use of third party evaluators such as consumerlab.com. But it’s not enough to educate the physicians. As long as these products are over the counter, we need to make sure they are safe and effective, and that the public knows how to use them.
Maizes is the executive director of the University of Arizona Center for Integrative Medicine and an OpEd Project Public Voices Fellow.