The Alliance for Natural Health USA (ANH-USA) advised caution over the New York Attorney General’s claim that some large-retailer store-brand herbal supplements may not contain the herbal compounds they advertise. According to Gretchen DuBeau, ANH-USA’s legal and executive director, the kind of test performed on those supplements is widely known to yield dubious and unreliable results.
“The AG sent cease-and-desist orders on the basis of only one testing technology from only one laboratory, by a scientist who frankly lacks the requisite expertise. It should be obvious that the results are preliminary and require further substantiation before taking such a rash action,” DuBeau said. “More to the point, the tests used DNA barcoding, a technology that is rarely able to identify chemically complex herbal extracts, since in many commercial extraction processes, little or no DNA is extracted. At minimum, additional testing using microscopic analysis and time-honored chemical methods should have been conducted to confirm the initial results.”
According to DuBeau, a number of factors make this type of testing problematic as well: an incomplete library of DNA sequences was used for comparison; fillers such as rice powder can produce mixed signals during the DNA sequencing process; and herbal products contain plant metabolites that may prevent accurate analysis.
DuBeau was quick to point out that most of the news reports about this incident seem to paint all nutritional supplements in a negative light, when the vast majority of manufacturers subject their herbal products to rigorous and open scientific testing.
At the same time, DuBeau said, recognizing the limitations of the particular tests used by the AG’s office is critical. “As a colleague pointed out, a dermatologist wouldn’t use a urine test to check for basal cell carcinoma. A botanist recognizes the drawbacks to using DNA barcoding exclusively to check for botanical identification. It doesn't tell the whole story. We just don’t have enough information about the attorney general’s study. It is hypocritical for the AG to demand transparency from supplement companies, as current Good Manufacturing Practices require, while not being transparent in his own testing procedures.”
DuBeau’s comments echoed statements from the Council for Responsible Nutrition, the American Herbal Products Association, and the Natural Products Association.
ANH-USA recently published a list of nutritional supplement companies known for their extremely high manufacturing standards, careful testing, and nutrient potency. Many of the companies offer USDA Certified Organic source ingredients. The consumer advocacy group recommends the following ways to make sure your supplements are of the highest quality:
- Always read the label. One way to compare ingredients in different products is by using the Dietary Supplements Labels Database, maintained by the National Library of Medicine.
- Do your research or talk to a health professional. Some supplements interact with one another and with different medications—sometimes well, and sometimes not! Moreover, some supplements should be taken in combination with others; for example, calcium needs to be taken with vitamins D3 and K2, or the calcium may migrate to the heart or circulatory system where it does damage, rather than to the bones where it is needed. A trained health professional can offer important advice.
- Talk to your supplement manufacturer. A reputable supplement manufacturer will always have a phone number where they can answer your questions about their ingredients, including where they come from and what safety procedures are in place.
- Check the FDA’s supplement website. This database warns the public about tainted supplements—the “bad actors” of the industry—that contain illegal pharmaceuticals or deceptively labeled ingredients. These products may be promoted for weight loss, sexual enhancement, and bodybuilding. The FDA also offers an RSS feed so consumers can be kept up to date with late-breaking additions to the database.