Stanford University researchers made the curious announcement this month that there is little difference between organic and conventionally grown foods. Their analysis of 237 relevant studies led to the conclusion that “the published literature lacks strong evidence that organic foods are significantly more nutritious than conventional foods.”
Still, they did note several nutritional advantages from eating organic foods. And proponents of organic eating quickly pointed out that reduced exposure to pesticides far outweighs the possibility of the foods’ greater nutritional value.
“There isn’t much difference between organic and conventional foods, if you’re an adult making a decision based solely on your health,” said Dena Bravata, MD, the senior author of the paper, which was published in the Sept. 4 edition of Annals of Internal Medicine. Dr. Bravata said she became interested in the topic because patients repeatedly asked her about the benefits of organic products.
The Stanford researchers did conclude that eating organic foods can reduce the risk of pesticide exposure. They also noted that there was a paucity of studies that directly compared the health benefits of eating an organic diet to a conventional one (just 17 of the 237 studies did so). The researchers found that organic fruits and vegetables had a 30 percent lower risk of pesticide contamination than conventional produce, but they downplayed the significance of that exposure.
Reacting to the Stanford news, Organic Trade Association executive director Christine Bushway said, “Organic foods have the least chemicals applied in their production and the least residues in the final products. And, because organic livestock practices forbid the use of antibiotics, including the routine use of low level antibiotics for growth, organic meat contains less antibiotic-resistant bacteria.”
The Stanford researchers noted that conventional chicken and pork has a 33 percent higher risk of contamination with bacteria that are resistant to three or more antibiotics compared to organic products. They also cited higher levels of beneficial phenols in organic produce, omega 3 fatty acids in organic milk and chicken, and vaccenic acid in organic chicken.
“The Natural Products Association is pleased that the Annals of Internal Medicine confirmed organic foods lower your exposure to pesticides and drug-resistant bacteria,” said NPA executive director John Shaw. “I think most Americans would agree these are extremely positive qualities of organic foods.”
Proponents of organic agriculture also cite its environmental benefits, which include more diverse insect life and far less runoff of fertilizers and chemicals into the water supply.
“5 Ways the Stanford Study Sells Organic Short” by Tom Philpott, Mother Jones, www.motherjones.com, 9/5/12
“Are Organic Foods Safer or Healthier than Conventional Alternatives?” by C. Smith-Spangler et al., Ann Intern Med, 9/4/12