In the recently published study of organic versus conventional agriculture, Stanford researchers concluded that organic foods were no more nutritious than their conventionally-grown counterparts. There’s one catch – the study was a meta-analysis. It’s a term that puts the nerdy-numbers-loving part of my brain on high alert.
What’s a meta-analysis, you ask? Well, it’s a study that aggregates the results from numerous studies, compiling them into one big picture. Sometimes it’s a useful tool – if you’re trying to get a big picture from a bunch of different researchers’ attempts to answer the same question in different ways. The problem with meta-analyses is that they are a notoriously unreliable methodology for discovering anything statistically significant about well… anything. A meta-analysis can shore up and confirm a known correlation (for instance, that smoking is correlated with lung cancer) but what it can’t do is find a definitive conclusion from a bunch of inconclusive studies. What does this study mean for the nutritional value of organic produce? Well, to know that, you’d have to know how reliable, rigorously designed, and methodologically comparable the “source” studies are.
When you go to the source, many of the studies are painfully flawed, both in their methodology and execution. For a great analysis of the devilish details that make this study one big flaw from start to finish, read Chuck Benbrook’s analysis in Civil Eats. The old dictum “garbage in, garbage out” comes to mind.
That said, it makes me wonder… what would a well-designed study of farming methods and nutritional value look like? Would it just be the dichotomy of organic vs. conventional, or would it take into account the soil building practices of the beyond-organic movement? My suspicion is that farms that focus on building high quality soil (rather than the big organic farms that simply use only organically-approved pesticides and fertilizers) would indeed produce more nutrient dense food! If your soil has more nutrients present, it stands to reason that the vegetables grown in that soil do too. But that’s a layer of complication that no study to my knowledge has addressed.
But back to this hypothetical study – how would you define “healthier” and what would be statistically significant? Is it simply nutritional value per calorie consumed, or is there a bigger picture in the health of our planet, our communities? Isn’t planetary health a PART of our health? How is it that we still need to ask that question?
It seems to me there is a larger issue playing out in this study and in the media coverage of the so-called results – that we have a deep disconnect between the health of our own bodies and the health of our planet. We are unable to see that we are all tied together. The fertilizer applied to my strawberries runs off into your water supply. The the pesticides that kill the bugs on your lettuce disperse into the air we all breathe. The soil that gets stripped away year after year in conventionally-managed fields leaves the surrounding wildlife, water, and air contaminated, weakened, and frighteningly vulnerable to both natural and man-made disaster. It’s all connected – but we are disconnected, unable to see the intricate links when we walk down the produce aisle.
But really, when it comes down to it, would anyone outside of academia ever assume that “health benefits” are defined by the nutrient density of a single piece of fruit? Would anyone but the mainstream media tell us how to eat, based on such a frivolous conclusion?