02/05/2015 04:30 EST | Updated 02/05/2015 05:59 EST

Health Canada Investigating Claim Many Herbal Supplements Are Fake

Health Canada is investigating claims from the U.S. that some herbal supplements don’t contain the ingredients advertised on their labels, and are instead packed with cheap filler materials.

New York Attorney General Eric Schneiderman sent cease-and-desist letters to four chains — Target, Walmart, GNC and Walgreens — earlier this week demanding they stop selling products that were DNA tested and found to be mislabelled.

Most of the chains have removed the offending products from shelves. GNC’s Canadian web store is temporarily closed. The company and Target Canada could not immediately be reached for comment.

The attorney-general found that four out of five of the store-brand herbal supplements tested did not contain any of the herbs on the label.

For instance, Walmart-brand echinacea actually contained none of the herb often used to ward off colds, while GNC bottles of St. John’s wort contained rice and garlic but not a trace of the root used to treat depression.

Walmart says it does not carry Spring Valley, the brand in question, in Canada.

Natural health products have been regulated in Canada since 2004. Health Canada said it is reviewing the information and if it is determined that “non-compliant” products are being sold in Canada, it “will take appropriate action based on the risk posed to the general public,” which could include on-site visits, public advisories or product seizures.

The department said all natural health products sold in Canada must comply with the Food and Drugs Act and Natural Health Products Regulations and quality is ensured through Health Canada’s licensing requirements for those products. But it's up to companies to ensure they are in compliance.

“Health Canada provides oversight of natural health products to help assure that they are safe, effective and of high quality,” spokesman Eric Morrissette said.

“The primary objective of Health Canada’s compliance and enforcement approach is to manage the risks to Canadians using the most appropriate level of intervention.”

The DNA tests were conducted on three or four samples of each product and each sample was tested five times.

New York’s investigation into the supplements was prompted by a New York Times story on a University of Guelph study published in the journal BMC Medicine in 2013, which found one-third of the supplements tested contained no trace of the plant listed on the bottle. The study used different brands of supplements bought in both Canada and the U.S.

“Most of the herbal products tested were of poor quality, including considerable product substitution, contamination and use of fillers. These activities dilute the effectiveness of otherwise useful remedies, lowering the perceived value of all related products because of a lack of consumer confidence in them,” the researchers concluded.

An earlier study conducted by the university found that the DNA barcoding testing technique is 88 per cent effective in determining the content of herbal supplements.

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