Organic food is like anything else on a grocery store shelves promoted by heavy marketing; buy it if you want but don't bug people how you are smarter than they are for doing so.
There is generally no difference in nutritional value or risk for bacterial contamination between organic and conventional foods, according to a new study published in Annals of Internal Medicine. While the consumption of organic fruits and vegetables reduced exposure to any detectable pesticide residues by 30 percent, pesticide levels were generally within the allowable limits for safety.
Researchers conducted a systematic review of 17 human studies and 223 studies of nutrient and contaminant levels in unprocessed foods such as fruits, vegetables, grains, milk, eggs, chicken, pork, and meat to compare the health, nutritional, and safety characteristics of organic and conventional foods. They found that the published literature lacks strong evidence that organic foods are significantly more nutritious than conventional foods.
"Some believe that organic food is always healthier and more nutritious," said Crystal Smith-Spangler, MD MS, a VA Physician Fellow at CHP/PCOR, and lead author of the paper. "My colleagues and I were a little surprised that we didn't find that."
The researchers did find weak evidence of the nutritional superiority of organic foods in that organic produce contained significantly higher levels of total phenols, a compound that may have antioxidant properties, and that organic milk and chicken contained significantly higher levels of omega-3 fatty acids. However, the researchers concluded that since few people have phosphorous deficiency, the finding has little clinical significance.
Sales of organic foods have increased dramatically is the US. Between 1997 and 2010 organic food sales have risen from $3.6 billion to over $26 billion annually. Prices vary, but consumers my pay up to twice as much for organic foods versus conventional. In general, to be certified "organic," produce must be grown without synthetic pesticides or fertilizers or routine use of antibiotics or growth hormones. Organic livestock are fed organically produced feed and are free to roam outdoors. In addition, organic regulations typically require that organic foods are processed without irradiation or chemical food additives and are not grown from genetically modified organisms.
"There are many reasons why consumers may choose to purchase organic food," said Smith-Spangler. "We examined published literature to assess the evidence for significant differences in nutrition, food safety, and health outcomes between organic and conventional foods and populations consuming these foods. However, consumers may choose to purchase organic foods for other reasons besides nutrition and food safety, such as concern for animal welfare, the environment, or preferences in taste."
Citation: Are Organic Foods Safer or Healthier Than Conventional Alternatives?: A Systematic Review, Crystal Smith-Spangler, MD, MS; Margaret L. Brandeau, PhD; Grace E. Hunter, BA; J. Clay Bavinger, BA; Maren Pearson, BS; Paul J. Eschbach; Vandana Sundaram, MPH; Hau Liu, MD, MS, MBA, MPH; Patricia Schirmer, MD; Christopher Stave, MLS; Ingram Olkin, PhD; and Dena M. Bravata, MD, MS, Ann Intern Med. 4 September 2012;157(5):348-366 http://annals.org/article.aspx?articleid=1355685