What I found disappointing about the Stanford study was the weakness of its analysis of differences in pesticide residues.
I was delighted to find that Steve Savage had posted a well-researched critique Do You Really Need to Buy Organic Foods To Avoid Pesticide Residues? of the meta-analysis “Are Organic Foods Safer or Healthier Than Conventional Alternatives?” The main-stream media didn’t get much further than the “Conclusion” paragraph of the press release
Conclusion: The published literature lacks strong evidence that organic foods are significantly more nutritious than conventional foods. Consumption of organic foods may reduce exposure to pesticide residues and antibiotic-resistant bacteria.
Every media reference I’ve encountered emphasizes the “…may reduce exposure to pesticide residues”. Does that mean “reduce exposure” from safe-and-totally-insignificant to…? Perhaps – but that really isn’t the focus of the Stanford paper – which is the nutritional vector. Steve’s introduction gets right to the implied pesticide risk that concerns me:
Last week, a meta-analysis from a highly credible, academic source (Stanford University, its medical school and nearby institutions), raised serious questions about the often-touted, nutritional advantage of organic food. They digested the contents of 237 peer reviewed articles comparing organic and conventional foods and diets. They concluded that “the published literature lacks strong evidence that organic foods are significantly more nutritious than conventional foods.” This drew a great deal of attention and organic advocate defense. Because even though Stanford is affectionately known by alums such as me as “the farm,” it is certainly no ag-school promoting the status quo. Instead, it enjoys a very strong reputation for research excellence. It isn’t easy to dismiss these findings.
Many commentators, confronted with the highly credible de-mythification of the nutritional advantage of organic, jumped to the paper’s slight evidence supporting a 30% reduction in exposure to pesticide residues as a way to justify paying extra for organic. Does the science really support that claim? No.
Please read Steve’s commentary with an open mind. If you are not completely persuaded, then for further reading may I suggest the B N Ames, M Profet, and L S Gold paper Dietary pesticides, which is an edited version of a chapter titled ‘Cancer Prevention and the Environmental Chemical Distraction‘, in the 2003 book Politicizing Science: the Alchemy of Policymaking. The Kindle edition is only $9.99, and a very good investment it is.