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A few weeks ago, word got out that a review being published in September’s American Journal of Clinical Nutrition had concluded that organic foods are not healthier or more nutritious that conventional food.

Organic advocates were outraged. Mildly engaged consumers began to wonder if organics were really worth the higher price tag.

Momentarily leaving aside some the review’s conclusions, my first thought was: Is higher nutritional quality really what motivates consumers to buy organic food, anyway? Isn’t it more about what’s not in the food than what is?

Most people I know who make a point of buying organic do so to avoid ingesting antibiotics, pesticides and other toxins. Sure, if my organic tomato had a few more vitamins than a conventionally grown one, that would be a nice bonus, but it’s not the reason I’m buying it.

And according to the Organic Trade Association, there are plenty of other good reasons to buy organic food that don’t have anything to do with what goes in your body. The association provides information on how organic agriculture can improve soil fertility, prevent chemical fertilizers from polluting waterways and accommodate higher species diversity.

The environmental reach of conventionally grown food is longer than most of us can even imagine. I stopped buying non-organic bananas after a short visit to Costa Rica revealed something about the industry I never would have known about: the use of plastic bags.

During my visit, my colleague and I drove past millions of banana trees, but I never saw a single banana. Instead, I saw big, blue plastic bags covering each banana bunch on every single tree.

My colleague explained that these bags were filled with pesticides and placed over the bananas to protect them from insects that might cause brown spots on the fruit, making them aesthetically unappealing to American consumers.

According to FleetWatch, these bags are used three times before being recycled, but locals will tell you that these blue bags are everywhere, littering the forest floor and choking rivers and streams.

But back to the review.

The review of 55 studies from 1958 to 2008 found that conventionally produced crops had a higher content of nitrogen, while organically produced crops had higher phosphorous and acidity content. No differences were found between the two classes of crops for the other nutrient categories — including vitamin C, zinc, and calcium — that were analyzed.

The review, funded by the U.K. Food Standards Agency, didn’t look for differences in pesticide residues between organic and conventional growing methods.

Organic advocates had strong objections to the review for a number of reasons.

Michael Hansen, Ph.D., a senior scientist at Consumers Union, cited the use of older studies as a major flaw. He told WebMD that most studies done before 1980 probably had flawed methodologies, and newer studies show clear differences in nutrient content between the two growing methods.

Secondly, the study doesn’t look at differences in polyphenols and certain antioxidants, which chief scientist for The Organic Center Charles Benbrook, Ph.D., says are 25 percent higher in organically grown food.

So, what does this mean for your food purchases?

Benbrook actually has some really sound advice: If you want to maximize the nutrient content of your produce, choose the freshest and most colorful fruits and vegetables. And if you want to minimize pesticide residues and environmental pollution, choose organic.

For now, my habits — choosing organic and local produce when I can — aren’t changing.

— Text by Margaret Southern, Cool Green Science Blog