A meta-analysis of 343 previously peer-reviewed studies from all over the world has found that organic crops contain more antioxidants and fewer pesticides than their non-organic counterparts, according to reporting in the Guardian.
The research, conducted by an international team of scientists led by UK professor of ecological agriculture Carlo Leifert, is published in the British Journal of Nutrition. It shows that the increased levels of antioxidants (between 18-69 percent) could have significant impact on human nutrition.
"If you buy, consistently, organic fruits and vegetables...you get one to even two extra servings of antioxidants from those organic foods compared to if you bought conventional brands," said Charles Benbrook, a Washington State University researcher and the lone American co-author of the paper.
The frequency of occurrence of pesticide residues was found to be four times higher in conventionally grown fruits, vegetables, and cereals, which also contained significantly higher concentrations of the toxic metal cadmium. Cadmium has been linked to kidney damage and cancer.
"Most importantly, the concentrations of a range of antioxidants such as polyphenolics were found to be substantially higher in organic crops/crop-based foods," the study found. "Many of these compounds have previously been linked to a reduced risk of chronic diseases, including [cardiovascular disease] and neurodegenerative diseases and certain cancers, in dietary intervention and epidemiological studies."
The study's findings run counter to those of the most recent comprehensive look at the same topic, which found, in 2012, "the published literature lacks strong evidence that organic foods are significantly more nutritious than conventional foods." That research synthesized the results of 223 studies.
The head of the UK-based Soil Association said in a statement:
"We know that people choose organic food because they believe it is better for them, as well as for wildlife, animal welfare and the environment, and this research backs up what people think about organic food. In other countries there has long been much higher levels of support and acceptance of the benefits of organic food and farming: we hope these findings will bring the UK in line with the rest of Europe, when it comes to both attitudes to organic food and support for organic farming.”
Sales of organic food are on the rise in the UK, after a years-long slump.