Using DNA analysis, the researchers first developed a DNA “barcode” library of over 100 different species of plants commonly used in herbal remedies. Then they compared the DNA barcodes of the herbal plant ingredients in 44 different herbal supplement products from 12 manufacturers against the barcode library. All of the tested products are currently available in the U.S. and Canada.
The results were, in a word, shocking. Only about half of the supplement products tested were “authentic”, meaning that the plant species listed on the product label was present in the product. However, that did not mean that the product was pure; a third of these authentic products contained contaminants and/or fillers such as rice, wheat or alfalfa. Of the 44 products tested, fully a third were complete fakes; they contained none of the herb listed on the label.
How about the quality of the different supplement manufacturers? The number of samples tested was small (only 44 products tested from 12 companies) so statistical analysis isn’t possible. Nevertheless, the researchers report that only two companies’ products were all authentic and free of contaminants or fillers. At the other end of the scale, the tested products of three companies were all complete fakes. The researchers did not provide the names of the companies, but wouldn’t we like to know?!
It’s “buyer’s beware” when it comes to herbal supplements. Take them at your own risk.