It would have been hard to miss the headlines and discussion on organic food this week. Essentially a very large study said there is no difference in nutrition or safety between organic and non-organic food. Because consumers often pay more for organic it gave pundits a great opportunity to mock those who take organic food seriously, but organic supporters did fight back.
We used to talk/argue about this a lot when I worked at CBC. My position for what it's worth was that nutrition was probably a wash given that most organic produce sold in Canada is harvested early and travels long distances just like conventional, that no pesticide residues is probably better for you, but most importantly land use by organic farmers (longer rotations, cover crops, etc) makes it a more sustainable choice. I'm fortunate enough to grow a fair percentage of the produce we eat and yes I do it organically, but again it's at a scale that I can.
Here's a couple of pieces with different viewpoints. No one said this would be easy.
http://www.nytimes.com/2012/09/07/opinion/roger-cohen-the-organic-fable.html?adxnnl=1&ref=opinion&adxnnlx=1347008533-oGag6dq888k7YOQLp+iw2Q&pagewanted=print
September 6, 2012
The Organic Fable
By ROGER COHEN
LONDON — At some point — perhaps it was gazing at a Le Pain Quotidien menu offering an “organic baker’s basket served with organic butter, organic jam and organic spread” as well as seasonally organic orange juice — I found I just could not stomach the “O” word or what it stood for any longer.
Organic has long since become an ideology, the romantic back-to-nature obsession of an upper middle class able to afford it and oblivious, in their affluent narcissism, to the challenge of feeding a planet whose population will surge to 9 billion before the middle of the century and whose poor will get a lot more nutrients from the two regular carrots they can buy for the price of one organic carrot.
An effective form of premium branding rather than a science, a slogan rather than better nutrition, “organic” has oozed over the menus, markets and malls of the world’s upscale neighborhood at a remarkable pace. In 2010, according to the Organic Trade Association, organic food and drink sales totaled $26.7 billion in the United States, or about 4 percent of the overall market, having grown steadily since 2000. The British organic market is also large; menus like to mention that bacon comes from pampered pigs at the Happy Hog farm down the road.
In the midst of the fad few questions have been asked. But the fact is that buying organic baby food, a growing sector, is like paying to send your child to private school: It is a class-driven decision that demonstrates how much you love your offspring but whose overall impact on society is debatable.
So I cheered this week when Stanford University concluded, after examining four decades of research, that fruits and vegetables labeled organic are, on average, no more nutritious than their cheaper conventional counterparts. The study also found that organic meats offered no obvious health advantages. And it found that organic food was not less likely to be contaminated by dangerous bacteria like E.coli.
The takeaway from the study could be summed up in two words: Organic, schmorganic. That’s been my feeling for a while.
Now let me say three nice things about the organic phenomenon. The first is that it reflects a growing awareness about diet that has spurred quality, small-scale local farming that had been at risk of disappearance.
The second is that even if it’s not better for you, organic farming is probably better for the environment because less soil, flora and fauna are contaminated by chemicals (although of course, without fertilizers, you have to use more land to grow the same amount of produce or feed the same amount of livestock.) So this is food that is better ecologically even if it is not better nutritionally.
The third is that the word organic — unlike other feel-good descriptions of food like “natural” — actually means something. Certification procedures in both the United States and Britain are strict. In the United States, organic food must meet standards ensuring that genetic engineering, synthetic fertilizers, sewage and irradiation were not used in the food’s production. It must also be produced using methods that, according to the Department of Agriculture, “foster cycling of resources, promote ecological balance and conserve biodiversity.”
Still, the organic ideology is an elitist, pseudoscientific indulgence shot through with hype. There is a niche for it, if you can afford to shop at Whole Foods, but the future is nonorganic.
To feed a planet of 9 billion people, we are going to need high yields not low yields; we are going to need genetically modified crops; we are going to need pesticides and fertilizers and other elements of the industrialized food processes that have led mankind to be better fed and live longer than at any time in history.
Logically, the organic movement should favor genetically modified produce. If you cannot use pesticides or fertilizers, you might at least want to modify your crops so they are more resilient and plentiful. But that would go against the ideology and romance of a movement that says: We are for nature, everyone else is against nature.
I’d rather be against nature and have more people better fed. I’d rather be serious about the world’s needs. And I trust the monitoring agencies that ensure pesticides are used at safe levels — a trust the Stanford study found to be justified.
Martin Orbach, the co-founder and program director of the Abergavenny Food Festival in Britain, owns a company called Shepherds that produces a superb sheep’s milk ice-cream sold at a store in Hay-on-Wye. It has a cult following at the Hay literary festival and beyond. Journalists, Orbach told me, regularly report that they have eaten an “organic sheep’s milk ice cream.”
The only catch is this is not true. “We have never said it’s organic because it would be illegal for us to do so,” Orbach said. “But it fits with the story of a small sheep’s milk ice-cream maker.”
Organic is a fable of the pampered parts of the planet — romantic and comforting. Now, thanks to Stanford researchers, we know just how replete with myth the “O” fable is.
http://www.motherjones.com/tom-philpott/2012/09/five-ways-stanford-study-underestimates-organic-food
5 Ways the Stanford Study Sells Organics Short
by Tom Philpott
Indiana Public Media/Flickr
Is organic food little more than a trumped-up marketing scheme, another way for affluent consumers to waste money? A just-released paper by Stanford University researchers—and the reaction to it by the media—suggests as much. (Abstract here; I have a copy of the full study, but can't upload it for copyright reasons.)
"Stanford Scientists Cast Doubt on Advantages of Organic Meat and Produce," declared a New York Times headline. "Organic food hardly healthier, study suggests," announced CBS News. "Is organic healthier? Study says not so much, but it's key reason consumers buy," the Washington Post grumbled.
In reality, though, the study in some places makes a strong case for organic—though you'd barely know it from the language the authors use. And in places where it finds organic wanting, key information gets left out. To assess the state of science on organic food and its health benefits, the authors performed what's known among academics as a "meta-analysis"—they gathered all the research papers they could find on the topic dating back decades, eliminated ones that didn't meet their criteria for scientific rigor, and summarized the results.
In another post I'll get to the question of nutritional benefits—the idea, expressed by the Stanford authors, that organic and conventional foods are roughly equivalent in terms of vitamins and other nutrients. What I want to discuss now is the problem of pesticide exposure, and why I think the Stanford researchers are underestimating the risks.
In short, the authors' findings confirm what the Environmental Working Group, crunching USDA data, has been telling us for years: that organic fruits and vegetables harbor significantly fewer pesticide residues than their chemically grown peers. Summing up the evidence of the studies they looked at, the Stanford researchers find what they call a 30 percent "risk difference" between organic and conventional food—which to the mind not trained in statistics, sounds like organic foods carry 30 percent less risk of exposing you to pesticides. And they immediately undercut that finding by noting that the pesticide traces found in both organic and conventional food tend to be at levels lower than the Environmental Protection Agency's maximum allowed limits. Takeaway: Conventional produce carries trivially small levels of pesticides, and you might as well save your money and forget organic.
What's wrong with this comforting picture?
1. Conventional produce is much worse than organic on the pesticide-exposure question than the 30 percent number suggests. That's what Chuck Benbrook, research professor at Washington State University' Center for Sustaining Agriculture and Natural Resources, shows in a detailed critique of the study. To get the 30 percent number, the authors used an odd statistical construct they call "risk difference." By their method, if 5 percent of organic vegetables contain at least one pesticide trace and 35 percent of conventional vegetables contain at least one trace, then the "risk difference" is 30 percent (35 minus 5). But that's a silly way of thinking about it, because there's a much greater difference between those numbers than "30 percent" suggests. Crunching the authors' own raw data, Benbrook finds "an overall 81% lower risk or incidence of one or more pesticide residues in the organic samples compared to the conventional samples."
But even that doesn't get to the full extent of the study's underestimation, since:
2. To arrive at their "risk difference" metric, the authors didn't distinguish between a single pesticide trace and multiple traces; or between light traces and heavier traces. For their purposes, an organic apple carrying a tiny residue of a relatively innocuous pesticide is equivalent to a conventional apple containing a cocktail of several relatively toxic pesticides. Here's Benbrook on why that's silly:
a) most residues in organic food occur at much lower levels than in conventional food, b) residues are not as likely in organic foods, c) multiple residues in a single sample are rare in organic food but common in conventional produce, and d) high-risk pesticides rarely appear as residues in organic food, and when they do, the levels are usually much lower than those found in conventional food (especially the levels in imported produce).
Now, the authors might reply that all of this is trivial, because the traces that researchers find on produce, whether conventional or organic, almost always come in at levels below the EPA's safety threshold. But:
3. This ignores a growing body of research that pregnant women's fetuses can be harmed at low exposures of organophosphate pesticides, as can young children.
And what's more:
4. The authors—like the EPA itself—ignore the "cocktail effect" of exposure to several pesticides, say, from a single apple. As Environmental Working Group's analysis of USDA data shows, conventional produce like apples, blueberries, and bell peppers often carry traces of many pesticides. The EPA regulates pesticide traces only on an individual basis, disregarding possible synergistic effects. The European Commission is starting to take them more seriously. Here's a report commissioned by the European Commission in 2009:
There is a consensus in the field of mixture toxicology that the customary chemical-by-chemical approach to risk assessment might be too simplistic. It is in danger of underestimating the risk of chemicals to human health and to the environment.
Which brings us to the fifth point:
5. We probably know more about how exposure to low levels of multiple pesticides affect amphibians than we do about how they affect people—and what our amphibious friends are telling us isn't pretty.
In short, the Stanford study seriously underplays the benefit of going organic to avoid pesticide traces, especially for vulnerable populations like pregnant women and kids. In a future post, I'll show why it does the same for exposure to antibiotic-resistant pathogens in meat, and doesn't give organic its due with regard to nutritional benefits.
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