The Soil Association called yesterday for schools to provide organic meals. If you think this sounds wholesome, you are conning yourself. Every TV chef and lifestyle magazine tells us that organic food tastes better and is safer than other food. Supermarkets promote it and the Government subsidises farmers to grow it. Britain would, we are told, be healthier and our countryside would once again prosper if only we all went organic.

In fact the craze for organic food is built on myth. It starts with a scientific howler, has rules with neither rhyme nor reason, none of the claims made for it have ever been substantiated and if it grows, it will damage the nation’s health.

To start with, the high priests of the organic movement tell us that natural chemicals are good and synthetic chemicals bad. This is utter nonsense. A molecule is a molecule, whether it is made by a synthetic process or a natural one. Many synthetic drugs that kill bacteria are highly beneficial; many natural chemicals are highly poisonous. Arsenic, ricin, aflotoxin are all highly poisonous chemicals found in nature. Yet the supposed superiority of “natural” over synthetic is the rock on which the organic movement is built.

Next, the rules that organic farmers have to follow are a marvel of inconsistency. They allow the use of some pesticides, for example spraying with the toxic Bacillus thuringiensis (Bt), but the Soil Association, which makes the rules, bitterly opposes using part of the Bt gene in GM crops, although this avoids the need to spray. In fact, Bt spraying kills useful insects that are not pests and so is worse for the environment, whereas a GM crop uses Bt to target specific insects. Again, the use of an inorganic fungicide, copper sulphate, is allowed; more effective, safer fungicides are banned.

But is not organic food safer because it contains fewer pesticide residues? Scares about residues are another myth. As Sir John Krebs, the head of the Food Standards Agency, wrote: “A single cup of coffee contains natural carcinogens equal to at least a year’s worth of carcinogenic synthetic pesticides in the diet.”

Does it taste better? Many people swear it does; but blind tests show no one can tell the difference: the belief is sheer hype. As to biodiversity, a study at Boarded Farms in Essex, comparing like with like, namely the same farmer’s organic and non-organic fields, showed that what matters is management. Well-managed conventional farming was no worse for wildlife; indeed a system of integrated farm management was better than organic farming for biodiversity and used less energy and labour.

Every time organic farming claims are objectively examined, they are rejected. When a complaint was made to the Advertising Standards Authority about Soil Association leaflets claiming that organic food is tastier, healthier and better for the environment, it was upheld and the leaflets had to be withdrawn.

Some argue that it does not matter if such claims are false and organic food costs more, since consumers are willing to pay and organic farmers profit. But it does matter. Since organic fruit and vegetables are more expensive, if organic products take a bigger market share, low-income families — and children at less well-funded schools — will eat less fruit and fewer vegetables. They will lose the protection against cancer that a healthy diet provides and more of them will die younger. Cheap food may be a luxury to the prosperous (and vocal) middle classes, but not to the lower paid.

But perhaps the most extraordinary thing about organic farming is that the Government wants it to expand. We the taxpayers have to pay.

Lord Taverne is chairman of Sense About Science

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