'I hope you get cancer and then look in the mirror." That is a pretty representative sample from the Bad Science mailbag last week, so I shan't be writing about mobile phone masts again until you all calm down. But it's in the backlash that you can find the truth. This week some fabulous elderly scientists came out loudly against homeopathy on the NHS.

A maelstrom ensued, and critics focused mainly on the failures of modern medicine: the side effects, and the failures, as if these problems could somehow be subtracted from medicine and given to alternative therapies as a benefit. In that backlash, you can see a whole century of medical history.

Before 1935 we were basically useless. Then suddenly, between about 1935 and 1975, science poured out a constant stream of miracle cures. Everything we associate with modern medicine happened: antibiotics which could save you at 21 and let you die at 70; dialysis; transplants; intensive care units; CT scanners; heart surgery; almost every drug you've ever heard of, and more.

As well as the miracle cures, we were finding those hidden killers that the media still desperately pine for in their headlines. Smoking, in the 1950s, to everybody's genuine surprise, turned out to cause 97% of lung cancers.

Then, rather suddenly, for the most part the breakthroughs stopped, and the subtle refinements began. We can shave percentages off here and there, but it's marginal. So you get dogged headlines like Is This the Cure For ME? in the Daily Mail, last week. This was apparently based on a conference presentation, not a published paper, reporting just 12 people treated for chronic fatigue syndrome with an antiviral drug, apparently without a control group. You can't read it, or critique and assess the methodology, because it's not published.

It feels pretty wet alongside, say, the invention of the coronary bypass: but the media still wants the miracle cures and the hidden threats. They try to convince you that one glass of wine a day can prevent a heart attack.

But we want perfect health, which is where homeopathy comes in. The World Health Organisation defines health as "a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity". That is a tall order and to pretend science and medicine can serve up your immaculate physical, mental and social well-being will create nothing but disenchantment.

We will have backache. We will get colds. We will be shy, and sad. And that is where homeopathy is valuable: often medicine can do little for these problems, which have become the focus of our health worries; and where medicine can do nothing, it should step aside. We may be tempted to offer drugs, as placebos at least, but drugs have side effects, and sometimes they're not worth it.

During the cholera outbreak of 1854, the London Homeopathic hospital had a death rate of 13%, rather better than the Middlesex hospital's death rate of 53%. Neither medicine nor homeopathy could do anything to treat cholera then, but medicine's attempts - bloodletting, for example - had dangerous side effects, and it's the same bargain today.

If you're treating the untreatable, if the NHS is there to serve up WHO's definition of immaculate well-being, then that's like trying to cure cholera in 1854: at least with homeopathy, the side effects only affect our intellect

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