Wednesday, October 19, 2011

A slight rant about organic agriculture

The scientific blogging community has largely become a voice not just for science, but also for skeptical inquiry. Legions of established scientists, scientists in training, citizen scientists, science enthusiasts, and everyone in between have made it a personal collective mission to evaluate claims about the world at large with an eye towards interpretations backed by evidence. Rightly so, this cadre of skeptics tears apart claims of the paranormal, faith healing, alternative medicine and other quackery in the name of evidence and reason.

There is a sort of "dark side" to all this, however, in that some things get a bad reputation due to their close proximity or endorsement by people who generally accept worldviews contrary to those of the skeptic army. One such field that has a tendency to get shit all over by skeptics is the organic foods movement. One would assume that a movement that largely aims to reduce pesticide use in farming, decrease the dependence on monocultured growing practices, and take a skeptical view on GMO crops wouldn't be too difficult of a sell for most anyone with a basic understanding of ecology. Unfortunately the tendency for proponents of organic agriculture to have a decidedly "anti-science" attitude tends to draw the skeptic community like flies, and they waste no time denouncing these "wackos" and criticizing the entire shebang. Now, it is fair to say that there are some legitimate criticisms of the organic movement, especially with the increasing desire to commercialize and oversell the claims made...but this doesn't mean we should throw the baby out with the pesticide-free bathwater!

A few months ago one of the shining stars of the science-blogging community, Christie Wilcox, published an article that aimed to "bust some of the myths about organic agriculture" that unfortunately came across as a denouncement of the movement as a whole. One Jason Mark, editor of an environmental quarterly and manager of an organic farm, took Christie's myths point-by-point with a very capable rebuttal. Now, I am not going to break down and meta-analyze an internet dust-up from a few months back, but I am going to say that the initial post was indicative of the claims I am making- that many skeptics tend to classify organic agriculture as something full of fanciful notions and anti-science. The tone is similar to what I have experienced; it comes across as a sort of backhanded compliment, or a subtle denouncement.

 "I'm not saying that organic agriculture is really stupid, but yeah organic agriculture is pretty stupid,"

I was reminded of this attitude when a colleague of mine gave a lecture about the impacts organic agriculture can have on biodiversity. Dave Crowder published a paper last year that demonstrated how increases in species evenness is encouraged by organic farming methods (1). Furthermore they also were able to link increases in evenness to lower levels of pest species outbreak, and thus to increases in overall plant biomass (which is a way to demonstrate pest damage. Higher plant biomass means that less plant tissue was damaged by pests). I was thrilled by his presentation, not just because it confirmed my own bias*, but also because the research was presented without the subtle undermining from the scientific community I had become accustomed to. Dave was not the only ecologist to mention the benefits to biodiversity that organic practices engender, although he was one of the first to look at species evenness(relative levels of all species present) instead of richness(number of different species present).

In fact as I began to dig into the literature I found an increasing amount of scientific backing for the organic movement, or at least for the practices. For example, Hunter et. al earlier this year released a review article examining studies of nutritional content in organic crops versus conventional, and found that there was a significant increase in the amount of available micronutrients in organic crops (2). Lester and Saftner also found, on average, an increase in nutritional quality for most metrics in organic crops. They caution, however, that their results are inconclusive and that accurate and definite comparisons are difficult to ascertain (3).

*My own bias is that I am a supporter of the movement, largely based on the ecological benefit of organic practices versus conventional farming.

To continue the spirit of full disclosure, I will admit that yes there ARE some serious problems with the organic movement, and many of its proponents ARE vehemently anti science. To give a personal example, I used to work at the health food chain Earth Fare, and one of their stores had a banner that proudly proclaimed "Our farmers wear overalls, not lab coats!". It is easy to see how this attitude can turn off the skeptical movement, who are largely driven by the scientific process and lead scientists to write off the entire organic movement, which is perhaps a bit unfair. There is some good science and some strong arguments that can be made based ON that science for the organic agriculture movement, and while we skeptics are within our rights to question the movement, there is enough data at present to speak for the legitimacy and benefits of organic agriculture.

  1. Crowder, D. W., Northfield, T. D., Strand, M. R. & Snyder, W. E. Nature 466, 109-112 (2010)
  2. Hunter et. al Evaluation of the Micronutrient Composition of Plant Foods Produced by Organic and Conventional Agricultural Methods. Critical Reviews in Food Science and Nutrition 51:571–582 (2011)
  3. Lester, G. E. and Safter, R. A. Organically versus Conventionally Grown Produce: Common Production Inputs, Nutritional Quality, and Nitrogen Delivery between the Two Systems. J. Agric. Food Chem. 59, 10401–10406 ( 2011)

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