September 30, 2014
It’s still National Organic Month! To celebrate, I thought it fitting to read a new research study comparing the nutritional quality of organic crops versus conventional crops. I like to keep current on this topic since the scientific community can confidently say that organic food has less of an impact on the environment and is safer for the health of farm workers and farm communities compared with conventional farming, but the nutritional difference is still up in the air. I wait eagerly for the verdict.
There have been a few review studies similar to this one in the past few years, most not finding a significant difference in the nutrients of the crops. This is most likely because measuring the nutrient content of crops is a very difficult task. It is influenced by a wide variety of factors including soil quality, weather, crop type, and growing practices, so it’s tough to compare apples to apples.
This new study summed up the results of 343 individual studies, many of them having never been including in a review before. It found some significant differences is nutrients.
Organic crops found to have more antioxidants
On average, organic crops had 18-69% higher amounts of certain antioxidants than conventional crops. Interestingly enough, organic crops had lower amounts of vitamin E. Organic crops had lower levels of protein and fiber. These differences are most likely due to the added nitrogen in conventionally grown crops.
Not surprisingly, this study found food grown organically to have 10-100 times lower amounts of pesticide residues. This fact may make you squirm, but amounts are still below the limits set by the Environmental Protection Agency. However, limited research suggests even low-level exposure to pesticides and herbicides may be linked to potentially negative health outcomes, especially in children and babies in utero, but I’m still waiting for stronger evidence of this.
Conventional or organic—eat your veggies!
And so our understanding of the nutritional differences of organic and conventional food continues to expand, currently in favor of organic. Still, the health benefits of eating 2 ½ cups of vegetables and 2 cups of fruit a day far outweighs the potential risks of any pesticide residues.
Barański, M. et al. Higher antioxidant and lower cadmium concentrations and lower incidence of pesticide residues in organically grown crops: a systematic literature review and meta-analyses. Br J Nutr. Sep 14, 2014; 112(5): 794–811. Published online Jul 15, 2014. doi: 10.1017/S0007114514001366
McCullum-Gomez C. Commentary: Role of organically produced foods in reducing exposure to synthetic pesticides in children’s diets. Diabetes Spectrum. 2010. 23(5): 254-256.
Bouchard et al. Attention-Deficit/Hyperactivity Disorder and Urinary Metabolites of Organophosphate Pesticides. Pediatrics, June 2010 : http://www.ncbi.nlm.nih.gov/pubmed/20478945