Sunday, April 01, 2007

scientific evidence is growing that organic food is better for you

Peter Melchett

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is policy director of the Soil Association, a UK organic food and farming organisation.

Bearing fruit

The scientific evidence is growing that organic food is better for you. But our politicians are still too wedded to the food industry to admit it.

March 30, 2007 2:00 PM | Printable version

organicveg.jpg
Eat yourself fitter: organic veg at a farmers' market. Photograph: Frank Baron.


The newspaper headline this week that stated "Proof at last that organic apples can be better for you" was perhaps slightly more tentative ("can be" not "are") than first appeared. Several scientific studies published in the last few days have indeed confirmed earlier research findings that organic milk, meat, fruit and vegetables generally have more beneficial nutrients, and less harmful or potentially harmful substances, than non-organic. Will this be enough to convince die-hard opponents of organic food and farming that it really is better for you? No it won't - those who have a fanatical belief in pesticides and GM crops will go on opposing organic with an unnatural fervour whatever the facts. At least they will until the oil and natural gas runs out - and with it the feedstocks for the pesticides and artificial fertilisers that intensive and GM farming relies on. Before that happens, will this new research change David Miliband's opinion, expressed earlier this year, that there is no proof of health benefits from eating organic?

First, what did researchers actually find? American research on organic and non-organic kiwi fruit was carried out by scientists at the University of California Davis, a university known for agricultural research that has generally focused on the benefits of intensive farming and GM crops. The researchers said: "All the main mineral constituents were more concentrated in the organic kiwi fruit, which also had higher ascorbic acid (vitamin C) and total polyphenol content, resulting in higher antioxidant activity. It is possible that conventional growing practices utilise levels of pesticides that can result in a disruption to phenolic metabolites in the plant that have a protective role in plant defence mechanisms". They found organic kiwis had 17% more polyphenols - antioxidants that reduce the production in the body of harmful chemicals called free radicals. The organic produce was also found to have 14% more vitamin C and greater concentrations of several important minerals such as potassium and calcium.

European researchers found that organic tomatoes "contained more dry matter, total and reducing sugars, vitamin C, B-carotene and flavonoids in comparison to the conventional ones", while conventional tomatoes in this study were richer in lycopene and organic acids. Showing that these comparisons can throw up some variation in how beneficial organic is, previous research has found that organic tomatoes not only have higher levels of vitamin C and vitamin A, but also of lycopene. In the latest research, the scientists conclude "organic cherry and standard tomatoes can be recommended as part of a healthy diet including plant products which have shown to be of value in cancer prevention".

A French study has found that organic peaches "have a higher polyphenol content at harvest" and concludes that organic production has "positive effects ... on nutritional quality and taste". In the study of apples, organic apple puree was found to contain "more bio-active substances - total phenols, flavonoids and vitamin C - in comparison to conventional apple preserves" and the researchers conclude "organic apple preserves can be recommended as valuable fruit products, which can contribute to a healthy diet".

All this confirms a list of officially accepted, beneficial nutritional differences (or lower risk) between organic and non-organic food. These include the Food Standards Agency's (FSA) advice to consumers that eating organic food is one way to reduce consumption of pesticide residues and additives and the Agency's agreement that recent research at Liverpool University shows organically produced milk can contain higher levels of types of fats called short-chain omega-3 fatty acids, and higher levels of alpha-linolenic acid (ALA) than conventionally produced milk. Beef produced from animals fed a diet high in forage (organic standards require that cattle be fed predominantly on forage-based diets) rather than grain, has reduced saturated fatty acid concentrations and enhanced content of omega-3 polyunsaturated fatty acids. No hydrogenated fats are allowed in organic food, and the FSA say that "the trans fats found in food containing hydrogenated vegetable oil are harmful and have no known nutritional benefits".

So someone buying organic food to reduce their intake of saturated fats, or avoid hydrogenated fats, where evidence of harm is widely accepted, is making a rational choice on health grounds. Equally, an organic shopper, who, in the absence of definitive scientific evidence either way, reasonably believes that the accepted nutritional differences or absence of pesticides and artificial additives in organic food will benefit them or their children, is also making a rational, health-based choice about their food. Those determined not to acknowledge the benefits of organic sometimes try and change the question - of course some non-organic food also avoids trans fats, cows don't have to be organic to be fed all-grass diets, and what affects our health most is eating a balanced diet containing plenty of fruit and vegetables whether organic or not.

So what of Miliband's "there is no proof of health benefits from eating organic"? In some respects he is clearly wrong. If generally agreed nutritional advice about the dangers of trans fats or the benefits of ALA are right, eating organic is the way to be sure you are making the healthier choice. And of course, even if in some areas of human health and diet there is still "no proof of health benefits from eating organic", there is equally absolutely no scientific proof that eating organic is not healthier.

the Bertrand Russell 'Teapot circling the sun' arguement; doesn't mean the teapot exists or that organic food is healthier!

It will always be difficult, maybe impossible, for scientists to do controlled studies on large numbers of human beings over long periods, to show the impact of an organic diet versus a non-organic diet. Controlling diets, and the huge number of other variables that affect our health, make identifying subtle impacts hard or impossible. Science cannot answer all questions. So other factors come into play.

People generally use their experience and their common sense. They may well know someone whose allergies cleared up when they switched to an organic diet, or they may feel better themselves when they eat organic food. They may know that organic farming and food is scientifically proven to be better for wildlife and farm animals, that it builds healthy soils, that it causes less pollution and that organic farming generally caused much less global warming. They may also know that it causes less stress to animals and plants, and that it is a simpler system, relying on few or no artificial chemicals. It is a sure way of avoiding GMOs.

And with the latest research, they may hear that there is now plenty of scientific evidence that many organic foods contain higher levels of beneficial nutrients compared to non-organic. It is certainly clear that our planet will be healthier if all farming was organic. All this may not prove people will be healthier if they eat organic, but it does seem a pretty reasonable conclusion to draw.

Reasonable, that is, until you factor in the politics. Miliband's problem, as others in government, the National Farmers' Union and elsewhere have said, is that they simply cannot announce that over 90% of the food we all buy or eat, the non-organic food, is less healthy, or even unhealthy, compared to organic. Ultimately, this is a political not a scientific issue. Once a third or a half of UK farming is organic, such an admission will be politically possible. Until then, we rely on the common sense of citizens. In what is still my favourite comment on all this, a member of the public told the BBC: "I take my vegetables seriously, but I take my politicians with a pinch of salt."

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