There are many claims that eating “organic” food is healthier and better for you. Intuitively, this may seem obvious, but the claims are not really supported by the evidence.
A study out of Stanford University called Are Organic Foods Safer or Healthier Than Conventional Alternatives? was published in the Annals of Internal Medicine in 2012. To investigate, the Stanford researchers worked through thousands of studies to analyze the 237 that most rigorously compared organic and conventional foods.
Over the past dozen years, U.S. sales of organic-labelled foods increased seven-fold to $27 billion. Canadian results are likely proportional. Given the size of this business, there has only been limited good research about the relative benefits of organic versus conventional foods. And because consumers pay up to double for the organic label, the question becomes even more relevant.
The term ‘organic’ refers to a set of practices for farming and processing agricultural products from fruits and vegetables to dairy products and meat. At its core, organic farming is designed to encourage soil and water conservation and reduce pollution. Certification varies around the world but generally organic foods are grown without synthetic pesticides or fertilizers nor are antibiotics or growth hormones routinely used.
The Stanford study’s findings bring into question some of the claims promulgated by the ‘organic’ industry. Specifically, they explain that “despite the widespread perception that organically produced foods are more nutritious than conventional alternatives, we did not find robust evidence to support this perception.”
The study found that while conventional produce has a 30 per cent higher risk for pesticide contamination than organic produce, the clinical significance of this finding is not clear because the difference in risk of contamination with pesticide residue exceeding maximum allowed limits is small. The study could not find any difference in the risk for contamination of produce or animal products with pathogenic bacteria. Both organic and conventional animal products were commonly contaminated with Salmonella and Campylobacter species.
The researchers did find that conventional chicken and pork have a higher risk for contamination with bacteria resistant to three or more antibiotics than were organic alternatives. This higher rate of antibiotic resistance may be attributable to antibiotic use in livestock, but the inappropriate use of antibiotics in humans is still the major cause of antibiotic-resistant infections in humans.
Organic diets expose consumers to fewer pesticides, and organic farming has been shown to have less impact on the environment than conventional operations. But there is no evidence of meaningful nutritious benefits from an organic diet, and there are no good studies showing disease protections from one.
There are many reasons why someone might choose organic foods over conventional foods, from environmental concerns to taste preferences, but when it comes to individual health, there isn't much difference.
Editor’s note: Dr. Paul Martiquet is the Medical Health Officer for Rural Vancouver Coastal Health including Powell River, the Sunshine Coast, Sea-to-Sky, Bella Bella and Bella Coola.