With thanks to The Telegraph and Will Storr 20.11.11:

Over and over again, the doctor told her she was being silly. But Gemma knew there was something wrong. She’d fall asleep on the sofa and couldn’t be woken. She’d see strange shapes and colours. She was having difficulties remembering things in the office. And yet every time she saw the doctor, he would say the same thing: you’re just a young girl, panicking.

Eventually, they found tumours on her brain, and they grew and spread. They tried chemotherapy. She felt sick. She gained four stone in four weeks. Her hair fell out over one weekend. She had to lift her eyelids with her finger to see. She had a wheelchair, a stick. Her bowels stopped moving. Her sight was so bad she couldn’t watch television or read. So she just lay there.

Then, in October 1995, the oncologist visited her hospital bed. “These are your options,” he said. “You can stay here, you can go to a hospice or you can go home.” Gemma was groggy; confused. She thought, well, let me think: sick people go to hospital, dying people go to a hospice, fit people go home.

“I’ll take home.” “Well,” said the doctor. “You’ve got those little pills and you’ve got Him up there. Make sure you have a happy Christmas.” It took Gemma a while to realise that this was her doctor’s way of telling her the cancer was, in fact, terminal.

Despite her dark prognosis, she carried on taking the “little pills” her oncologist had mentioned with a gently patronising smile. They’d been given to her by a homeopath recommended by her sister-in-law – she went out of politeness, really. But the more she took, the better she felt. At Christmas, her eyelids opened up. Her sight returned. A year later, she saw her oncologist. He wrote in his notes: “Gemma has made a remarkable recovery. Her case will remain a mystery.” But it wasn’t a mystery to Gemma, who has been telling me her story in the front room of her modest Sutton Coldfield house over the past hour. Gemma Hoefkens believes those little homeopathic pills had not only saved her life but changed it. She’s now a practising homeopathist who claims not to have been to the doctor for years.

Available on the NHS and for sale in Boots, homeopathy is an industry worth £40 million a year in the UK alone (and $1.4billion in the United States). And yet Gemma’s doctor wasn’t alone in his reservations. Throughout its weird and defiant 230-year history, homeopathy has attracted the fury of doubters all the way from Charles Darwin to Richard Dawkins. Over the past decade, the campaign against homeopaths has accelerated to such a pitch that questions have been asked in Parliament. In February 2010, the House of Commons Science and Technology Committee recommended the NHS cease funding the discipline, calling the £4 million that’s spent annually a “waste”. Tony Blair has even got involved, saying “my advice to the scientific community would be [don’t] bother fighting a great battle over homeopathy”. But they do and they are.

That same February, Gemma told her story on BBC Radio Five Live. Someone posted the interview on YouTube. On the video, every time Gemma speaks, a yellow rubber duck appears with the word “Quack!” flashing out of its mouth. At the end of the video, a photograph of Gemma herself appears. It says, “DO NOT BE FOOLED. HOMEOPATHY IS A CROCK OF S—”.

I unfold a print out of Gemma with a yellow plastic duck over her face. She scowls towards the paper. “How professional are they?” she says. “Who are these people who are so unprofessional? You know, who are they?” I decided to find out.

In the bar of a Manchester hotel, a pale platoon of anti-homeopaths are getting politely drunk. These are members of the “sceptic” community, a large and swelling movement of activists and thinkers who campaign against people such as Gemma and on behalf of science and reason. They organise in loose “cells” up and down the country, in collectives known as “Sceptics in the Pub”, and gather online to compose irritable and unusually well-footnoted blogs.

This weekend, the sceptics are gathered for the “QED conference” that has been organised by the Merseyside branch of Sceptics in the Pub, led by a 27-year-old marketing executive named Michael “Marsh” Marshall. It will culminate in a mass international homeopathic overdose – a stunt that will seek to demonstrate that, as the campaign’s slogan has it, “there’s nothing in it”.

Invented in 1790 by German physician Samuel Hahnemann (who, like Gemma, had grown disillusioned with conventional medicine), the theory behind homeopathy says that illnesses can be cured by taking minute portions of substances which cause similar symptoms to those which ail you. So, if the bark of a toxic Peruvian tree causes symptoms similar to malaria, say, then a tiny dose of that can cure malaria. In Gemma’s case, her many maladies were, she believes, cured by causticum. When I inquired what causticum was, she said, “Er, you put it down drains”.

The amount of causticum in one of Gemma’s pills is unbelievably small. In fact, if you buy a standard “30C” dose, it means the active ingredient has been diluted 30 times, by a factor of 100. Your chance of getting even one molecule of the original substance in your pill is one in a billion billion billion billion. Imagine a sphere of water that stretches from the Earth to the Sun. That’s how much you’d have to drink to get just one solitary molecule of it.

This is why Marsh’s campaign’s slogan insists that “there’s nothing in it”. Homeopaths deny this, however, saying that when they dilute the substance, they first shake it (or “succuss” it) which “potentises” the water, causing it to somehow remember the active substance.

I accuse Marsh and his sceptics of being curmudgeons. Even if it is expensive water, so what? He responds with the case of an Australian baby, Gloria Thomas, who was diagnosed with eczema aged four months and died five months later after it became infected. Her father, a homeopathy lecturer, insisted on treating Gloria with his diluted remedies rather than conventional medication. When he was imprisoned in 2009, the judge blamed Gloria’s death, in part, on her father’s “arrogant approach” to homeopathy.

“I find cases like that genuinely distressing,” says Marsh. “Homeopathy is magic. It’s 18th-century magic. That’s what we’re trying to get across with the overdose. To the people who might wander into Boots with a headache and say ‘Homeopathy – I’ll try that’, we want to say ‘there is no evidence for homeopathy. The science has been done. It simply doesn’t work’.” The day’s final act is sceptic singer George Hrab. I leave the convention hall for bed as he attempts to lead the reluctant sceptics in a sing-a-long: “You won’t believe what a sceptic I am/I can’t believe you believe in that sham…”

Sceptic after sceptic at the QED conference told me the same thing: “There is no evidence for homeopathy”. But this isn’t absolutely true. Dr Alexander Tournier of the Homeopathy Research Institute tells me, “This is very spurious. If you talk to sceptics they will acknowledge, for example, a paper that was published in The Lancet in 2005, which is known as ‘Shang et al’. That included 110 respectable studies of homeopathy [that showed some positive effects]. One-hundred and ten trials! You can’t say that’s nothing.”

Tournier himself became an adherent when he was studying quantum physics at Cambridge University and he became ill with the Epstein Barr virus, a form of chronic fatigue. Homeopathy, he says, cured him. He explains that homeopathy has been available on the NHS since 1948, and that a 2007 study found that six million Britons were users and it was increasing at a rate of around 20 per cent a year. “There’s also a big tradition of homeopathic hospitals, like the one in London.” He means the Royal Homeopathic Hospital, founded in 1849 and renamed “The Royal London Hospital for Integrated Medicine”. It offers complementary treatments, including homeopathy, alongside conventional medicine.

One GP I speak to admits to an “establishment bias” around homeopathy, but approves of its undeniably powerful placebo effect – “even prescription by a doctor has one,” he says. Ultimately, though, he believes “the balance of evidence isn’t overwhelming enough yet” for him to use it.

I contacted Dana Ullman, a homeopath who has become the industry’s chief defender in the US, to find out what he makes of the sceptics. (One had described him to me as “despicable”.) “Some of them are big pharma shills [stooges], others are just misinformed,” says Ullman, on the phone from Berkeley, California.

I ask Ullman about the Lancet paper mentioned by Tournier. A team from the University of Berne in Switzerland, led by one Professor Aijing Shang, sought to finally answer the question of whether or not homeopathy works by doing a meta analysis, which essentially blends the results of lots of studies in an attempt to find The Ultimate Answer. The resulting paper has since become iconic.

The team started by looking for studies of homeopathy that took into account the placebo effect – which is acknowledged by all as being remarkably powerful and can skew the results of any medical trial. Shang’s team ended up with 110 studies that looked at homeopathy’s effect on an array of medical conditions. They matched these with studies, looking at the same conditions, except using conventional medication. First, they analysed both sets of papers separately. They found that both conventional medicine and homeopathy showed a positive effect above placebo. Simply put, they both worked. Next, they looked at the quality of the studies. They found that the better the study was, the worse the result for homeopathy. Finally, they isolated eight studies which were of the very highest quality.

They concluded that evidence for homeopathy was “weak” and “compatible with the notion that the clinical effects of homoeopathy are placebo effects”. Shang et al essentially found that the better the study was, the more likely it was to show that homeopathy is no better than a placebo. It was published alongside an editorial headlined: “The End of Homeopathy”.

“Ha, ha, ha!” says Ullman, down the phone. “I laugh at sceptics who use Shang as their firmest body of evidence.” Ullman says that several studies showing strong effects for homeopathy were ignored by Shang et al for mysterious reasons. He says that a subsequent study of Shang accused them of “post hoc analysis” – gathering evidence and then deviously working out a way to prove homeopathy wrong.

He says that some of the studies included were not intended to show if homeopathy worked in the first place. Rather, they were exploratory “pilot studies”, carried out to test the design of a proposed full study. And yet negative results for pilot studies were taken by Shang to be conclusive.

Finally, Ullman disputes Shang’s assertion that a larger study will be of higher quality. He says that this ignores the basic principles of homeopathy. When you visit a homeopath, they talk for an hour and consider all sorts of apparently unrelated facts before deciding what to dispense. Ullman says this process of “individuation” means that small studies are more accurate, because these are more likely to be the ones in which the homeopath took the time to dispense an appropriate remedy.

When I list these complaints to Andy Lewis, author of the popular sceptical blog The Quackometer, he gives an amused yet sorrowful sigh. But of Ullman’s complaint that exploratory “pilot” studies were included, Andy admits: “Yes, the vast majority of homeopathy studies would be pilot studies. I don’t think the inclusion criteria took that into account.” Would he go so far as to say Ullman has a point? “Dana’s always wrong. So, no. I wouldn’t go that far.”

It took me a while to understand what I now hold to be the truth about homeopathy. I was in the thicket of Shang, trying to carefully understand everything Ullman was telling me, when I suddenly thought: if homeopathy worked, shouldn’t it be more obvious? If it really did have the power to cure a cancer as advanced as Gemma’s then wouldn’t we see, in study after study, significant wins for the homeopaths? Science moves forward by consensus. Unlikely claims backed up by marginal results cannot and should not lead to a change in establishment opinions.

And yet the sceptics are wrong when they say there’s “no evidence” for homeopathy. There is evidence. But there’s much better evidence that says it doesn’t work.

For me, it seems clear that Gemma’s recovery is a mystery. But her story does show that, for us fallible humans, personal experience will always trump the dry analyses of science. Indeed, as Gemma walked me to her door at the end of that afternoon, I asked her one final question.

If God sat you down and said, “homeopathy is nonsense”, would she believe him?

She answered in an instant. “No.”