Is organic food healthier?
After publishing a study showing organic milk has higher levels of omega-3 fatty acids than ordinarily farmed products, Professor Chris Seal braced himself for the backlash. There is nothing like a study highlighting the benefits, or lack thereof, of organic food, to cause a spat. And Seal’s study in the British Journal of Nutrition last week (alongside another by him on meat that also shows higher levels of omega-3 fatty acids) certainly has its detractors.
The fact that the study was funded by the Sheepdrove Trust, a British charity that supports organic farming, hasn’t helped. Seal says the money paid for analysis only, and that the charity didn’t have any input into the research. The study, a meta-analysis of 196 papers on milk (the other looked at 36 studies on meat), found that organic-grass-fed cows produced milk with 50% more omega-3 fatty acids than that from ordinary dairy cows. These fatty acids are linked to reductions in heart disease. But, while 50% sounds like a lot, full-fat milk is only 4% fat (semi skimmed is 2%) so this translates to an tiny amount more fatty acid in organic milk. Seal argues that if you added in organic cheese and butter, this would increase. But others point out you could get more nutritional benefit buying fruit and vegetables than hoovering up organic dairy produce.
There is no evidence that eating organic food makes a significant difference to your health. Seal’s paper has different findings to two meta-analyses in 2009 and 2012 that did not find a link between organic food and better health. Seal says his research has more studies that now make this link statistically significant – which is not the same as clinically significant. To link organic food with better health, a study would need two groups of people randomly divided into those eating organic and those eating non-organic food – but they would have to eat the same foods as each other for months. Even then, you could only measure levels of markers of disease such as cholesterol levels or weight.
So don’t hold your breath. People say they buy organic food because it has fewer pesticides, antibiotics and additives. They also think organic production is kinder to animals and the soil. A 2012 meta-analysis from Stanford did find pesticides residues in non-organic food – but in safe amounts. It boils down to whether you believe in safe amounts or not – and if you can afford to avoid them. But so far the research says that conventional healthy food has the same benefits as organic healthy food.