Some reasons to buy organics are well known: The French Agency for Food Safety recently confirmed that they contain more antioxidants, heart-healthy polyunsaturated fatty acids, iron, and magnesium than nonorganic foods. Even the UK review presented data showing more magnesium and zinc and more antioxidant phytochemicals, such as phenols and flavonoids, in organic crops. And a five-year study by 33 universities, research centers, and companies funded by the European Commission—believed to be the largest study of its kind—determined that organic produce such as cabbage and potatoes contained more vitamin C (another antioxidant); that organic tomatoes contained more nutrients overall; and that organic dairy foods contained more omega-3 fatty acids and cancerfighting conjugated linoleic acid (CLA). This study, which will be published spring 2010, also uncovered lower levels of such contaminants as heavy metals, mycotoxins (by-products of fungal infections), and pesticide residues in organic foods. Several studies have linked pesticides used on conventionally grown produce to the neurological diseases Alzheimer's and Parkinson's.

A lack of pesticide exposure is an important reason organic produce has higher levels of beneficial antioxidants like vitamin C, which fight the free radicals implicated in aging, cancer, and heart disease. Antioxidants are actually part of a plant's own defenses. In fruits and vegetables, these bitter elements help fend off attacks by bugs and fungi. Organic crops contain more of these compounds because they have to work harder to protect themselves—no man-made pesticides to the rescue, says Holden.

In addition, organic produce is free of synthetic nitrogen fertilizer, which can also weaken plants' health. "Nitrogen produces a watery, sugary cell sap that compromises the plant's ability to build its immune system," says Holden. Plants that come to rely on the chemical can no longer fend off pests naturally. Crops that are treated with the synthetic fertilizer also have overly leafy growth and poor flavor, as farmers have long known. That's because the plants' natural immune system of antioxidants is what makes produce aromatic and savory. In other words, a healthy plant makes a healthy meal—and a tastier one.

The same could be said about animals. You are what they eat. In 2006 the Journal of Dairy Science published the results of a British study showing a direct link between organic farming and higher levels of omega-3 fats in cow's milk. According to the research, the average pint of (British) organic milk contains 68.2 percent more omega-3 fats than nonorganic milk. That makes sense: Grass (rather than corn and soybeans) is what cows will eat when left to their own devices, and it's loaded with these essential fatty acids. In one of the unfortunate oversights in U.S. organic regulations, cows on some large-scale organic farms rarely graze on fresh grass, and instead are largely confined to feed lots. But this year a new USDA rule should close the loophole. To find dairy products that are produced from pasture-grazed cows, check the Dairy Scorecard at

While studies have shown that organic food can contain more nutrients, recent data highlights specific benefits to those who eat it. A 2007 Dutch study published in the British Journal of Nutrition found that babies who ate organic dairy (and whose nursing mothers did, too) had a 36 percent lower incidence of eczema. A separate 2007 Dutch study found that women who drink organic milk have breast milk with much higher levels of CLA, a fatty acid with significant antioxidant properties.

In the end it's clear that organic food is worth the premium it commands at the grocery store. As the authors of the UK review put it themselves: "The differences in...nutrients and other substances between organically and conventionally produced crops and livestock products are biologically plausible and most likely relate to differences in crop or animal management, and soil quality." That's sciencespeak for precisely what organic farmers have said all along. Organic farming is not merely about eliminating bad things, like weed killer. It's about raising soil fertility with proven methods, both modern and traditional, such as mulch and compost. So it shouldn't come as a surprise that the healthier the soil, the healthier the plants and animals that depend on its nutrients—us included.

Nina Planck is the author of Real Food (Bloomsbury USA) and Real Food for Mother and Baby (Bloomsbury USA).

More O: Celia Barbour on the sustainable food movement


Next Story