Whether or not herbal supplements are of any benefit medically is an important question that can be investigated by well thought-out studies that are done honestly and with a scientific approach, but that issue is secondary to the question of the accuracy of product labelling of herbal supplements.
A recent study from Canada, employing DNA fingerprinting, has found that 60% of the herbal supplements contained unlisted components, with a large proportion not even containing the advertised herbal supplement as the major constituent. Given the lack of controls over the production of these products, and the unscrupulous nature of some herbal supplement purveyors, focused more on profits than on medical care for their clients.
Read more about my comments and criticisms of vitamin and herbal supplementation in THE GUIDE, pages 14-17