Edzard Ernst: We need less opinion and more scientific research

There is no good evidence to show that the prescriptions of herbalists do more good than harm

About three decades ago, the then-minister, Baroness Trumpington, promised that "over the next few years we expect to review some 700 herbal products" and stated "it is right that full proof of efficacy should be demonstrated before a licence is granted". Since then, much lip service has been paid to the regulation of herbalism, but anyone who goes into a health-food shop tomorrow can still buy a herbal remedy that has no proof of efficacy and is subject only to scant quality and safety control.

In April 2011, this will change. A new EU directive will legislate that a licence for a herbal medicine will be given only if it has been available for a long enough time, if its safety has been established scientifically and if it is of sufficiently high quality.This must be a good thing, because it should reduce the risk to consumers.

But what about the promised "full proof of efficacy"? It will still not be a requirement, which is lamentable, not least because treating a disease with an ineffective medicine can, of course, do much harm, too. It seems as though manufacturers' interests were put above those of consumers.

And what about regulating the herbalists? The Department of Health gave about £1m of our tax money to Prince Charles's Foundation for Integrated Health to facilitate such regulation. Shortly before the foundation had to close amid a fraud and money laundering investigation, a draft document finally emerged. It turned out to be so useless that it prompted protests.

Crucially, it failed to commit herbalists to practice according to best evidence, which, I think, puts the interests of herbalists above those of the public.

There is no good evidence to show that the prescriptions of herbalists do more good than harm. True, some herbal medicines are supported by sound evidence. For instance, St John's wort is scientifically proven as a treatment for depression. But, if you are depressed and consult a herbalist, she is unlikely to give you St John's wort. Herbalists usually prescribe adventurous mixtures of several herbs based on assumptions of health and disease.

Herbalists had years to get their act together and do their homework. Yet, instead of submitting their practice to proper scientific tests, they spent their funds on lobbying. We need more research.

Edzard Ernst is professor of complementary medicine at Exeter University