Organic foods are almost invariably more expensive than their conventionally produced counterparts but they aren't necessarily healthier or more nutritious, new research suggests.
Scientists found no consistent differences in vitamin content between organic and conventional foods and few significant differences in health benefits. They did note, however, that organic produce is 30 percent less likely to be contaminated with pesticides than conventional fruits and vegetables — though the pesticide levels of all foods fell within allowable limits — and that organic chicken and pork appeared to lessen exposure to antibiotic-resistant bacteria.
"I think different people will make different decisions based on our findings," said study author Dr. Crystal Smith-Spangler, an instructor at Stanford University School of Medicine and a physician-investigator at the VA Palo Alto Health Care System, in California. "We thought we'd find more significant differences, but there are many reasons why someone might consume organic foods. Health is one, but they may be concerned about the environment, animal welfare practices or taste, and we weren't evaluating that."
The study was published on the 4th of September in the Annals of Internal Medicine.
Organic products are generally grown without synthetic pesticides, fertilisers, irradiation or chemical food additives and without routine use of antibiotics or growth hormones. Organic livestock are offered freedom of movement and access to the outdoors and are fed pesticide- and animal byproduct-free organic feed.
Only one nutrient, phosphorous, was found to be significantly more abundant in organic produce, but researchers felt this had little clinical significance since few people are deficient in phosphorous. Also, no difference in protein or fat content was observed between organic and conventional milk, though limited previous studies did suggest organic milk contains markedly higher levels of omega-3 fatty acids, which may lower the risk of conditions such as heart disease, cancer and arthritis.