Great news for farmers, consumers and our overfished seas, or so we are told. The biotechnology industry in America claims it has invented something that could finally live up to the promises of 20 years ago and benefit consumers and the environment as well as farmers. It is a soya bean genetically modified to produce the omega-3 fatty acids that reduce the risk of heart disease and confer a wide range of other health benefits.

The main source of omega-3 fatty acids has hitherto been fish oil. So Monsanto’s GM soya bean, which has just received a notice of safety from the US Food and Drug Administration, could, it is claimed, relieve pressure on the world’s fish stocks as well as improving the health of millions. In the process it could make people who loathe GM technology, such as the Prince of Wales, have to eat their organic Fairtrade cotton hats.

Or could it? When I first read these remarkable claims in New Scientist last week, I found myself plunged back into familiar territory, a kind of big sky country where nothing is ever undersold and where nothing is what it seems.

Don’t get me wrong, I have never been entirely at home with those who believe genetic manipulation goes against the will of God. We’ve been at it for centuries anyway. Nor am I one of those who would refuse a designer heart if it happened to have been grown in a pig. I believe we should at least listen to people such as our chief scientist, Professor John Beddington, and his colleagues at the Royal Society who think Britain must not rule itself out of the GM technology market and that GM technology could one day be needed to feed the world.

That is not a trivial task. The wobble in the world’s food supply that began two harvests ago, which set rice and grain prices soaring, made scientists think about how we can feed a society of 9 billion people in 40 years’ time. Since the green revolution in the 1960s, world food production has risen from 1.84 billion tons to 4.38 billion tons. Scientific development is clearly vital to the new agricultural revolution — as Professor Sir David Baulcombe, chairman of a Royal Society study, said last month. It is just that there are different views about which technology has the answers. Indeed the most immediate things that the society recommends — using ecology to manage pests in crops, for example — aren’t anything to do with whizzo GM science at all.

The green revolution succeeded but its ugly downside was that industrial agriculture did not do much for the countryside, the rural poor, or arguably the quality of our food. In the countries that used the first GM crops, the same features have persisted and pesticide use has soared — contrary to predictions. GM monocultures have grown at the expense of rainforest and the climate. The big biotech companies have made huge profits.

Which brings us to the question of whether the new GM soya is going to feed the world — or is it really designed to feed the American appetite for food additives? Certainly an omega-3 enhanced oil that doesn’t taste of fish and could be added to margarine and other processed foods has its attractions. The soya oil with omega-3s that Monsanto has engineered seems to be taken up by the body more efficiently than current linseed-based additives. The crop is more suited to temperate North America than Brazil, so it might not displace much rainforest.

Will it take pressure off the world’s fish? I’m not so sure. GM soya isn’t going to stop people catching small fish and grinding them up as fishmeal. Monsanto says its soya is primarily designed for feeding to humans, not fish, so the big problem of finding substitute foods for farmed fish remains unresolved.

The greatest fallacy would be to suggest that Monsanto’s new product might somehow tackle the problem of the 84,000 Americans who died of heart disease and might not have done if they had eaten a sufficient amount of fatty acid in their diets, according to a 2005 study. Those people who died of heart disease had poor diets. Eating a healthy balanced diet gives you enough omega 3s without any need for additives in processed food. For the same reasons, hunger, poverty and nutritional problems in the developing world can’t be fixed by growing commodity crops. What people need are better diets.

What nobody tells you about GM crops is how far off are those that are theoretically worthwhile. Compared with air travel, biotech is still building with wire, wood and paper. Remember golden rice, the crop that was going to address vitamin A deficiency? That’s still under development. The Royal Society says that developing crops that are resistant to disease, drought, salinity, heat and heavy metals will take eight to 16 years. It will take longer than that to develop wheat or rice capable of fixing nitrogen from the air, thus reducing the need for fertiliser.

Monsanto’s new soya is undoubtedly part of a new era. The agri-business giants have learnt from their failure to win general public approval, particularly in Europe. They have realised that to achieve that they must provide benefits to the public. I suspect that biotech companies will eventually invent something we need — and the opposition to GM, justified until now, will fall away. But does the world need Monsanto’s fishy soya? The jury is out.

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