We ve said repeatedly that the Dietary Supplements Health Education Act (DSHEA) passed in 1994 put consumers at risk from unregulated or under-regulated supplements. The latest study confirming that opinion was just published in BMC Medicine.
Dr. Steven G. Newmaster and colleagues from the University of Guelph, Ontario Canada, and Bharathia University, India examined 44 herbal products with 30 herbal species from 12 companies. They also examined 50 leaf samples from 42 herbal species. Using DNA barcoding technology, they conducted blind tests of the authenticity of the samples. All the products tested are available in North America.
The results were disheartening. Over half of the products were found to contain DNA from plant species that weren t listed on the labels. One-third of the products also had unlisted contaminants and fillers. Only 2 of the 12 companies sold products with no substitutions, contaminants or fillers.
Most concerning, the authors found contamination in several products with plants that have known toxicity, side effects and/or negatively interact with other herbs, supplements, or medications. One example they noted was a supplement labeled as St. John s Wort that actually contained senna, a laxative, but no St. John s Wort at all. Senna, they state, can have adverse effects such as chronic diarrhea, liver damage, and abdominal pain and should not be used long-term.
Yet another contaminant was feverfew, an herb that shouldn t be used by pregnant women, and which reacts with several medications. Some Ginkgo products were contaminated with black walnut, as were some Echinacea products an obviously dangerous situation for consumers with nut allergies.
DSHEA allows dietary supplement manufacturers to market products without first affirming their safety to the FDA as pharmaceutical products are required to do. This leaves consumers unprotected against the kinds of errors or perhaps fraud documented in this study.
ACSH s Dr. Josh Bloom, who has been regularly writing about the deficiencies in the regulation (the lack, really) of supplements wonders why anyone should be surprised. He says, Last week there was a story of people in Hawaii developing severe liver disease from an absurd supplement called OxyElite Pro, which, even if the label is correct (and if you believe this I wish you all the luck in the world, because you re going to need it) contained (among other things) a synthetic stimulant called DMAA primarily used for weight loss and sports performance enhancement. Why DMAA, which has been implicated in a number of deaths, is sold as part of a dietary supplement, defies logic.