When you buy an herbal supplement that says “echinacea” or “ginko boloba” on the label, you may expect that it contains some additional ingredients beyond the advertised herbs, but you should be confident that those herbs are present. However, DNA tests commissioned by the New York state Attorney General found evidence that many herbal products may not contain what they advertise.

New York AG Eric T. Schneiderman has dispatched letters to Walgreens, Walmart, Target and GNC, calling on these retailers to immediately halt the sale of certain store-brand herbal products found to not contain the ingredients touted on their labels. The letters also ask these companies to provide detailed information relating to the production, processing and testing of herbal supplements sold at their stores.

Of all the store-brand herbal products tested from these stores, only 21% turned up DNA from the plants listed on the products’ labels, while 79% of the results showed either no DNA related to the labeled content or turned up contamination from other plant material, including rice, beans, pine, citrus, asparagus, primrose, wheat, houseplant, wild carrot, and others.

At Walmart, only 4% of the tested products showed DNA from the plants listed on the labels, making it the worst of the bunch.

For the testing, researchers obtained multiple samples of each of the six supplement types — Gingko Biloba, St. John’s Wort, Ginseng, Garlic, Echinacea, and Saw Palmetto — and tested each sample five times. In all 78 samples were tested 390 times.

GNC:
Of the “Herbal Plus” brand supplements purchased and analyzed, only the Garlic supplement consistently turned up as containing what was advertised. One bottle of Saw Palmetto tested positive for containing DNA from the saw palmetto plant, while three others did not. The remaining four supplement types yielded mixed results, but none revealed DNA from the labeled herb, according to Schneiderman. In all, DNA results matched the labels only 22% of the time.

TARGET:
The retailer’s “Up & Up” fared the best of the four retailers, with DNA tests confirming 41% of the labels, but that still means that over half the products tested failed to contain what was advertised. The most consistent supplements were Garlic and Saw Palmetto. Echinacea was also somewhat consistent, says Schneiderman, though one sample apparently turned up rice DNA.

WALGREENS:
Subpar results here, with tests finding that only 18% of the tested Walgreens’ “Finest Nutrition” brand supplements lived up to their labels. Once again, Saw Palmetto was the most consistently accurate label, while Schneiderman says the others generally failed to show DNA of the advertised plant matter.

WALMART:
Which brings us to the worst-performing of the store-brand supplements. As mentioned above, only 4% of the tested “Spring Valley” brand herbal supplements showed DNA of the advertised herbs. None were consistently accurate, says Schneiderman, though tests showed some garlic in one Garlic supplement sample, and some saw palmetto in one Saw Palmetto sample.

Unlike medications, which are heavily scrutinized by the FDA, herbal supplements are not subject to a rigorous evaluation process. But you still can’t advertise that you’re selling one thing and sell consumers something completely different. That’s why Schneiderman’s office is looking at potential violations of New York’s General Business Law and Executive Law.

“This investigation makes one thing abundantly clear: the old adage ‘buyer beware’ may be especially true for consumers of herbal supplements,” said Schneiderman in a statement. “The DNA test results seem to confirm long-standing questions about the herbal supplement industry. Mislabeling, contamination, and false advertising are illegal. They also pose unacceptable risks to New York families—especially those with allergies to hidden ingredients. At the end of the day, American corporations must step up to the plate and ensure that their customers are getting what they pay for, especially when it involves promises of good health.”

“The evidence for these herbs’ effectiveness is sketchy to begin with,” said David Schardt, Senior Nutritionist of the Center for Science in the Public Interest. “But when the advertised herbs aren’t even in many of the products, it’s a sign that this loosely regulated industry is urgently in need of reform. Until then, and perhaps even after then, consumers should stop wasting their money. Attorney General Schneiderman has done what federal regulators should have done a long time ago.”

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