Herbal supplements, sometimes called botanicals, aren’t new. As a matter of fact, the use of medicinal plants is the most common form of traditional medication worldwide. They have been used by human medicine for thousands of years. A considerable part of commercial pharmaceuticals currently on the market are derived from botanical sources. Examples include aspirin (from willow bark), quinine (from the quinine tree) and digoxin (from the foxglove plant). But pharmaceuticals have gone through extensive testing, herbal supplements have not.
The international trade in herbal supplements is a considerable part of the global economy and the demand is increasing in both developing and developed nations. There are currently more than 1,000 companies producing medicinal plant products with annual revenues in excess of US$60 billion. Echinacea to prevent colds. Ginkgo to improve memory. St. John’s wort to treat mild depression. Flaxseed to lower cholesterol. The list of herbal remedies goes on and on. There are now a bewildering 29,000 different products available on the market.
New research uncovered fraud
There is nothing inherently wrong in trusting herbal remedies, as long as you know what you’re getting. And do you? Maybe not according to new research.
Using a test called DNA barcoding, a kind of genetic fingerprinting that has also been used to help uncover labelling fraud in the commercial seafood industry, Canadian researchers tested 44 bottles of popular supplements sold by 12 companies. They found that pills labelled as popular herbs were often diluted — or replaced entirely — by cheap fillers like soybean, wheat and weeds. A bottle labelled as St. John’s wort was made of nothing but rice. They also found that many supplements were not what they claimed to be. For instance, the study found that one product advertised as the North American black cohosh, a popular remedy for hot flashes and other menopause symptoms, actually contained the related Asian baneberry plant that can be toxic to humans.
Some herbal supplements were discovered to be adulterated with ingredients not listed on the label. Such contamination could pose serious health risks to consumers. For example, they identified black walnut contamination in a gingko product and contamination of many products with Santa Maria feverfew. This latter plant can trigger respiratory and skin reactions in people. One of the bottles tested even contained Alexandrian senna, a powerful laxative made from an Egyptian yellow shrub.
Product substitution occurred in 30 of 44 of the products tested and only two of the 12 companies had products without any substitution, contamination or fillers. Many people assume that if their local pharmacy or health food store carries a particular herbal supplement, it can’t be harmful. But it certainly can since many contaminants will have significant medical effects.
How serious is it?
Some of the adulteration problems may be inadvertent. Cross-contamination can occur in fields where different plants are grown side by side and picked at the same time, or in factories where the herbs are packaged. Rice, starch and other compounds are sometimes added during processing to keep powdered herbs from clumping, just as kernels of rice are added to salt shakers.
But it is clear from the results that product adulteration and deliberate ingredient substitution is not uncommon as species of a lower market value are substituted for those of a higher value. This practice constitutes not only product fraud, but according to the World Health Organization, the adulteration of herbal products can be a threat to consumer safety. And as if this is not enough, pesticides and heavy metals are often found at high levels in herbal supplements, but that will be a topic of a further blog.
Consumer advocates and scientists say the research provides more evidence that the herbal supplement industry is riddled with questionable practices. But of course industry representatives argue that the problems are not widespread.
You make up your own mind.
- Study: Most Herbal Supplements Contain No Herbs (webpronews.com)
- Testing Reveals Weeds And Rice Fillers Where The Herbs Should Be In Herbal Supplements (consumerist.com)
- Tests Show Herbal Supplements Are Often Fake (aarp.org)
- Herbal Supplements Are Not What They Seem (uniquedaily.com)
- Herbal Supplements Are Often Not What They Seem (nytimes.com)
- Herbal Supplements Found to be Fake and Toxic, Reveals (biospace.com)