Organic produce is nutritionally superior to so-called “conventional” produce, according to a comprehensive review conducted by researchers from the University of Aix-Marseille for the French food agency (AFSSA) and published in the journal Agronomy for Sustainable Development.

“This critical literature review indicates that organic agriculture, as developed until now, has the potential to produce high-quality products with some relevant improvements in terms of anti-oxidant phytomicronutrients, nitrate accumulation in vegetables and toxic residue levels,” the researchers wrote.

To be recognized as “organic,” a food product must be produced without the use of genetic modification or chemical fertilizers or pesticides, and must promote sustainable cropping methods. In the United States, organically produced meat and dairy must be raised without the use of synthetic growth hormones or antibiotics. Hormones and antibiotics are banned in animal production across the board in the European Union.

Recently the United Kingdom’s Food Standards Agency (FSA) reviewed existing research on the nutritional content of organic produce concluded that there was no difference, nutritionally, between organic and non-organic produce. The FSA study did not examine the reasons most often given by consumers of organic produce, namely benefits to the environment, farm workers, and consumer health due to lower chemical use.

Yet the AFSSA review calls the FSA’s conclusions into question. After conducting an “up-to-date exhaustive and critical evaluation of the nutritional and sanitary quality of organic food,” French researchers concluded that organic produce is clearly nutritionally superior.

Organic produce contains more minerals, such as iron and magnesium, than non-organic produce, and higher levels of antioxidants such as phenols and salicylic acid.

“Organic plant food overall contain double the amount of phenolic compounds,” the researchers wrote.