Does homeopathy work?

By Nathan Williams
Producer of Horizon: Homeopathy - the Test

I remember the first time I read an article about homeopathy and realised an astonishing fact - that most homeopathic remedies don't contain any remedy at all.

I had always thought, like many people, that homeopathy was similar to herbalism - but the article described how homeopaths take a substance and dilute it over and over again, until there isn't a single molecule left.

It seemed extraordinary that a chemist could sell a bottle of homeopathic arnica that didn't actually have any arnica in it. The most basic laws of science said that such a medicine would be worthless.

Yet homeopathy is incredibly popular and growing; it is available on the NHS and is used across the world.

This was a paradox I found fascinating: either science was fundamentally wrong, or millions of people were being fooled.

The idea for doing the programme came when we heard about some intriguing new results coming from Belfast.

Scepticism

A pan-European team claimed to have diluted a substance until there was nothing left and yet found it could still have an effect on human cells in a test tube.

If true, the results would turn much of science on its head and provide scientific backing for the principles of homeopathy.

Most people in the scientific community were sceptical. On the face of it, it was very difficult to know which side had the stronger case.

That was when we hit on the idea of organising our own experiment.

The sceptics complained that most researchers into homeopathy were themselves supporters of homeopathy.

The homeopathic side complained that most independent scientists dismissed their claims out of hand and refused to test them.

We wanted to organise an experiment that would be rigorous and impartial.

Extraordinary controversy

What was particularly fascinating about the new work was that it reopened one of the most extraordinary controversies in modern science, the Benveniste affair.

Jacques Benveniste was a successful and respected biologist working in a French government-funded institute.

Then in the 1980s, his team stumbled on what appeared to be a revolutionary discovery.

They had been working on a test involving human blood cells called basophils - immune cells that react to substances we're allergic to.

Normally they have a granulated look under the microscope and can be stained blue using a particular dye.

Truly astonishing result

He had discovered that when he added a substance that provokes an allergic response it caused the basophils to lose their granules.

But the truly astonishing result came when his team tried diluting the allergen and then adding it to the cells.

Normal science would predict that as the concentration got lower the reaction would get smaller until the cells didn't react at all.

But his team found that even at astronomical levels of dilution - similar to those used in homeopathy - the allergen still had a strong effect on the cells.

After years of wrangling, Benveniste succeeded in getting his results published in the prestigious journal Nature. It seemed to be a major victory for homeopathy.

But things soon turned sour when the editor of Nature visited Benveniste's lab along with the magician and paranormal investigator James Randi.

After a week of investigation, the Nature team decided that the results were nothing more than a delusion - the product of sloppy scientific methods. Benveniste believes to this day that he was the victim of a deliberate plot to discredit him.

Benveniste found himself ostracised by the scientific community, his research largely forgotten. And James Randi publicly bet a million dollars that no one could prove Benveniste had been right.

But now the new results in Belfast seemed to imply that he had. All that was needed was for the experiments to be replicated in an independent laboratory.

So Horizon decided to do its own basophil experiments and enlisted the help of the Royal Society, the Royal London Hospital, University College London and Guy's Hospital.

If we could show that ultra-high dilutions could still have a biological effect, then James Randi would have to pay up the million dollars.

If we found no effect it would call into question, once more, the very basis of homeopathy.

The results were unveiled in Horizon: Homeopathy - The Test, broadcast in England and Wales on Tuesday 26 November at 9pm on BBC Two. Viewers in Scotland can see the programme on Thursday 28 November at the same time on BBC Two.