You may have heard pundits discussing the findings of a British review of studies (source link below) that debates the nutritional value of organic foods versus those that are conventionally grown. After reviewing 162 studies published over a 50-year period (1958-2008), researchers found "no evidence of a difference in nutrient content between organically and conventionally produced foodstuffs," according to the report.
The main differences that were mentioned: Conventionally produced crops contained significantly higher amounts of nitrogen while organic crops had much more phosphorus and higher volumes of acidity. Those results only explain part of the story...
Unfortunately, the study sidestepped the presence of pesticides in foods, a point driven home by a 2006 Environmental Health Perspectives study that concluded organic diets reduced such exposures dramatically -- particularly malathion and chlorpyrifos -- among children.
Moreover, a trio of experts came to radically different conclusions about the superior nutritional value of organic foods, using another methodology and narrowing the span of their review of studies to the 1980s.
American Journal of Clinical Nutrition July 29, 2009
Seattle Times August 5, 2009
healthfinder.gov July 29, 2009