If the answer is “for my health” the answer, again, is probably—but not automatically. I happen to believe the organic dinner I served my family is healthier than a meal of the same foods conventionally produced, but I’d be hard-pressed to prove it scientifically. What I could prove, with the help of a mass spectrometer, is that it contained little or no pesticide residue—the traces of the carcinogens, neurotoxins, and endocrine disruptors now routinely found in conventional produce and meat. What I probably can’t prove is that the low levels of these toxins present in these foods will make us sick—give us cancer, say, or interfere with my son’s neurological or sexual development. But that does not mean those poisons are not making us sick: Remarkably little research has been done to assess the effects of regular exposure to the levels of organophosphate pesticide or growth hormone that the government deems “tolerable” in our foods. (One problem with these official tolerances is that they don’t adequately account for children’s exposure to pesticides, which, because of children’s size and eating habits, is much greater than adults’.) Given what we do know about exposure to endocrine disruptors, the biological impact of which depends less on dose than timing, minimizing a child’s exposure to these chemicals seems like a prudent idea. I very much like the fact that the milk in the ice cream I served came from cows that did not receive injections of growth hormone to boost their productivity, or that the corn those cows are fed, like the corn that feeds Rosie, contains no residues of atrazine, the herbicide commonly sprayed on American cornfields. Exposure to vanishingly small amounts (0.1 part per billion) of this herbicide has been shown to turn normal male frogs into hermaphrodites. Frogs are not boys, of course. So I can wait for that science to be done, or for our government to ban atrazine (as European governments have done), or I can act now on the presumption that food from which this chemical is absent is better for my son’s health than food that contains it.
Of course, the healthfulness of a food is not simply a question of its toxicity; we have also to consider its nutritional quality. Is there any reason to think my Whole Foods meal is any more nutritious than the same meal prepared with conventionally grown ingredients?
Over the years there have been sporadic efforts to demonstrate the nutritional superiority of organic produce, but most have foundered on the difficulty of isolating the great many variables that can affect the nutritional quality of a carrot or a potato—climate, soils, geography, freshness, farming practices, genetics, and so on. Back in the fifties, when the USDA routinely compared the nutritional quality of produce from region to region, it found striking differences: carrots grown in the deep soils of Michigan, for example, commonly had more vitamins than carrots grown in the thin, sandy soils of Florida. Naturally this information discomfited the carrot growers of Florida, which probably explains why the USDA no longer conducts this sort of research. Nowadays U.S. agricultural policy, like the Declaration of Independence, is founded on the principle that all carrots are created equal, even though there’s good reason to believe this isn’t really true. But in an agricultural system dedicated to quantity rather than quality, the fiction that all foods are created equal is essential. This is why, in inaugurating the federal organic program in 2000, the secretary of agriculture went out of his way to say that organic food is no better than conventional food. “The organic label is a marketing tool,” Secretary Glickman said. “It is not a statement about food safety. Nor is ‘organic’ a value judgment about nutrition or quality.”
Some intriguing recent research suggests otherwise. A study by University of California–Davis researchers published in the Journal of Agriculture and Food Chemistry in 2003 described an experiment in which identical varieties of corn, strawberries, and blackberries grown