Edzard Ernst, the world's first professor of alternative medicine, is stepping down.

In 1993, Edzard Ernst became the first person to hold a chair in complementary medicine. As he prepares for his retirement as head of the Complementary Medicine unit at the Peninsula College of Medicine & Dentistry, part of the universities of Plymouth and Exeter, UK, he tells Nature about his frustrations and successes in trying to force this field on the fringes of medicine into line with science.

How did you come to be involved in the area of complementary medicine?

I grew up in Germany, and in Germany, alternative medicine is quite mainstream, much more so than in Britain. By total chance, my first post as a junior doctor was in a homeopathic hospital, where I learned homeopathy, of course, but also acupuncture and other things. I was quite impressed by the fact that people improved and there were good clinical outcomes.

Then I changed career several times. Among other things I did a PhD in hemorheology, the study of the flow properties of blood, which changed my outlook a bit. I learned how to think critically. As doctors you don't necessarily learn how to think critically, unfortunately. I then went back into clinical medicine, became a specialist in rehabilitation medicine, a professor in Hannover, then a professor in Vienna.

Then one day I saw the ad for the first professorship in complementary medicine. I was fed up with Vienna because there was far too much administration and not enough research for my tastes. I applied, and I became a full-time researcher of alternative and complementary medicine.

What did you hope to achieve in setting up the complementary-medicine unit at Peninsula College?

I always felt very strongly that I would focus on subjects that are important in the United Kingdom. Therefore we focus on homeopathy, herbal medicine, acupuncture and spinal manipulation. I was also convinced that scientists need to be critical and sceptical, and that if you apply science to any field you don't want to prove that your ideas are correct, you want to test whether they are correct.

That seems like a tiny difference to most people, but in my field it's a very big difference. I think we're the only ones [in our field] who have understood that. Everyone else in alternative-medicine research uses 'science' to prove that their notions are correct and I think that is a very bad starting point.

Let's say that someone has been an acupuncturist, then decides to research the technique. That person, in my experience, [generally] wants to prove the value of acupuncture. This is a misuse of science, perhaps even an abuse of science. In my field, critical [evaluation] is seen as something negative. If somebody tells me 'you're so critical', to me it's a compliment; to them it's an insult.

There are a lot of people who are professors of alternative or complementary medicine now. Are you disappointed that they are not continuing your legacy of critical thinking?

I have to admit that it irritates me when people get academic titles who are in my view not up to the job. I hope my most lasting achievement will be to plant the seedling of critical assessment into the field.

We have had many more tangible achievements – we have published books that are generally seen as important both for laypeople as well as for healthcare professionals; we have started a series of conferences; we've published well over 1,000 papers. But I would hope that the idea of critical assessment is our most lasting legacy.

The good news is Exeter [has decided] to not close the unit. I'm very optimistic that whoever follows will build on this notion of critical assessment and thinking.

Do we spend enough on research into complementary and alternative medicine?

We actually pay in this country such a tiny amount that it is almost disgraceful. It is less than 1% of the National Health Service's research budget, and that clearly isn't enough if you consider that 20% of the population is using these things. If you look at specific populations, such as people with cancer, the percentage is even higher.

There needs to be more research, but it is more important to have good research. Misguided research is actually worse than no research.

Have you found that any alternative medicines are useful?

I found that homeopathy is pretty useless. I would have liked the evidence to go the other way because I trained as a homeopath. It would have been quite nice to win a Nobel prize by showing that 'no molecule' can have an effect, but the evidence is clearly against it.

In other areas, the evidence is much more positive. Acupuncture we have shown is useful to reduce pain for certain conditions, and that is generally accepted now.

There are lots of herbal medicines that are backed by very good evidence. The prime example has to be St John's Wort for depression. There we have around 50 clinical trials and the totality of this evidence clearly shows that it is at least as effective as mainstream treatments for mild to moderate depression.

Some people say that if alternative medicine works, it's not alternative, it's just medicine. Does it need separate scrutiny?

In a way, as an alternative-medicine researcher you're sitting on a branch and you're trying to saw off the branch on which you're sitting. In an ideal world if something demonstratively works it should be just medicine, not alternative medicine or any other label. But we do not live in the ideal world. Again St John's Wort is a very good example. We know it is effective, yet it is not a standard treatment for mild to moderate depression. It does take a while [for these ideas] to sink in. In this interim period I think the label is quite useful.

What will you do now?

The university will continue to employ me for another year and I'm approaching normal pension age anyway. But I fully intend to remain active, if not more active, and perhaps more outspoken than I was before. If you have no worries about upsetting your vice-chancellor, your dean and your colleagues then you tend to be more outspoken. I think you'll probably hear more rather than less from me