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BOOK REVIEW

The Wisdom of "Mom"

Steve Shapin

In Defense of Food: An Eater's Manifesto. Michael Pollan. xii + 244 pp. The Penguin Press, 2008. $21.95.

Some sciences have points of contact with common sense and lay concerns; others don't. Expert opinions on the existence of the Higgs boson or the dating of the Cretaceous period don't have much effect on everyday life, for example, nor are people likely to imagine that common sense qualifies them to speak out on those subjects. With other sorts of scientific claims, though, laypeople feel competent to weigh in. The so-called "soft sciences" are soft not because their methodologies aren't rigorous enough but because they cannot effectively discipline their objects of inquiry. They cannot control the range of people able and willing to say their piece. Such fields are expected to make good their claims in the messy arena of everyday practice, where essentially everyone can see whether the claims are valid. Michael Pollan's compact and eloquent new book In Defense of Food-much of which overlaps with his enormously popular 2006 release, The Omnivore's Dilemma-is both an argument about the state of play in nutrition science and a concrete instance of the problem of expert authority within one of the more attention-grabbing contemporary soft sciences.

Pollan does not think much of the current state of nutrition science. He is not himself a nutrition scientist, but then he does not think that he has to be one to have an opinion on the subject. Pollan is a science journalist and a distinguished professor of journalism. More important, he is a reflective eater. That is to say, he possesses—as we all do—a great deal of experience with eating and its consequences, and he has inherited—as nearly all of us have—a body of "tradition" and "common sense" that often sits uneasily alongside the findings of nutrition experts. "Cultures have had a great deal to say about what and how and why and when and how much we eat," Pollan notes, adding—daringly—that "when it comes to food, culture is another word for mom, the figure who typically passes on the food ways of the group."

"Mom"—and certainly "dad" too—may be in the dark when it comes to high-energy physics and paleontology, but "mom" is usually right when it comes to practical nutrition. That's not because "mom" has read and mastered the academic literature, but because what counts as nutritional expertise is pretty poor stuff, Pollan thinks, and because "mom" already knows as much as can be securely known in the area.

What's gone wrong with scientific expertise about food goes by the name nutritionism-a term Pollan takes over from the Australian sociologist Gyorgy Scrinis. Basically, nutritionism is a form of the better-known category scientific reductionism. It's a pathological form of science in which the virtues of foods, and of a human diet, are reduced to the measures of specific constituent nutrients.

It all started in the 19th century with the work of the English chemist William Prout, who identified the macronutrients protein, fat and carbohydrates, and the German chemist Justus von Liebig, who declared that three macronutrients in soil—nitrogen, phosphorus and potassium—were all that plants need to live and grow. Then it developed through early 20th-century research discovering such necessary micronutrients as vitamins and trace elements. Food was complicated, but scientific nutrition aimed to simplify dietary knowledge: Find out the chemicals that are good for you and make sure your food contains them; find out those that make for ill health and make sure your food has as little of them as possible.

The paradigmatic instance of nutritionism gone mad, Pollan suggests, is what he calls lipophobia. Those who have fallen prey to its extreme forms maintain that animal fat—in practically any amount—is bad for you. At one time, lipophobes suggested that the trans fats in oleomargarine were preferable to the saturated fat in butter. Today the dangers of trans fats are also officially recognized. In any case, lipophobia is still with us.

Pollan doesn't think that nutritionism is good science or that eaters should follow its dictates. He offers two main reasons for this assessment: One is that modern nutrition science is corrupt, and the other is that it grossly underestimates the complexity of its object. Nutritionism, Pollan argues, is sustained by the profit motives of the Big Food Industry. There's a lot more profit in highly processed than in "natural" foods. And if that processing results in the noticeable loss of some nutrient, then it can be put back in and health claims can be made for the product, as they have been for sliced white bread fortified with vitamins.

Yet even if so many nutrition scientists were not in the thrall of industry, nutritionism would still be bad science. It's a complicated stew down there in your stomach. The claims of anyone who purports to know what defined list of nutrients, in what quantity, makes for health, or what complex interactions take place between foods in your gut, should be viewed with skepticism. Scientific neatness may be intellectually desirable, but that neatness does not necessarily yield an adequate account of real-life eating and its practical consequences for your well-being.

Nutritionism is hubris—misplaced scientific confidence—and people who follow its recommendations are doing themselves a disservice. The "Western diet" as a whole, with its preponderance of highly processed foods (supplemented or not) and calorie-rich but nutritionally empty snacks, with everything eaten in immoderate amounts and in a rush, has led to the current epidemics of obesity, type 2 diabetes, heart disease and certain kinds of cancer. The problem is not cholesterol, or saturated fats, or a lack of fiber or zinc; it's the whole way we eat and live. (That, after all, was the original sense of the word diet.) If they are uncontaminated and consumed in traditional ways, individual foods and their naturally occurring constituents are almost never toxic.

The cures for false expertise are tradition, common sense and the wisdom of "mom": comfort food for the soul. The anxiety of keeping up with and rigorously following the dictates of academic expertise has to be balanced against any conceivable good this expertise might actually do you. And so Pollan dishes out what he calls some "algorithms" (rules of thumb) of healthy eating to put in place of nutritionism.

First, "eat food"—that is, "don't eat anything your great grandmother wouldn't recognize as food." Do not eat anything with ingredients you've never heard of (all those preservatives, colorings and emulsifying agents in highly processed edibles). And view any radical departures from tradition—Twinkies, say, or eating fast food on the run—with suspicion, even if solid epidemiological evidence is not yet in hand.

Second, "not too much." It's scarcely news that contemporary Americans are eating more than before—more calories, larger portion sizes, more often—and that this must have something to do with the obesity epidemic and its supposed consequences. The food industry may, as Pollan suggests, conspire against our ability to push back from the groaning board, but we do have free will, don't we?

Third, eat "mostly plants." Pollan isn't a vegetarian, and he's a great fan of grass-fed beef and wild game. Endearingly, he recommends "foraging for edible greens and wild mushrooms in the park." He's pretty sure that eating lower on the food chain and eating locally and seasonally are good for you (and, incidentally, the planet).

So Pollan speaks for robust common sense against academic expertise. This is one of many areas in our highly scientized culture where common sense has not yet been rendered mute. There's nothing at all wrong with that, and, indeed, the popularity of writing by informed nonscientists like Pollan is a reliable sign of just how vulnerable the authority of nutritional expertise may now be. What Pollan refers to as the "cacophony" of expert voices—saying "fiber is good for you" one day, "fiber makes little difference" the next—has called forth the humane skepticism that makes In Defense of Food so genuinely appealing. (This book is a bestseller, taking its place, ironically, alongside such very different dietary bestsellers as those celebrating the faddish Atkins, South Beach, Zone and Ornish diets.)

I wanted to stand and cheer when Pollan reminds readers that eating is about more than doing our expertise-informed best to avoid disease and extend life—and would be even if we really knew what kind of diet would guarantee health and longevity. Get a life, he advises; eat things that themselves have had a life; enjoy foods that taste good; sit down and have a proper meal with friends and family; have a glass of wine, whether it contains high concentrations of resveratrol or not. Salud! L'chaim! Cin-cin!

In all this, it scarcely matters that Pollan is a journalist and not a scientist: He's speaking back to expertise about what matters to him and about what his own experience and traditions testify, and he's got every right to do so. Yet Pollan can't quite leave it at that—he rather spoils the integrity of his performance with intermittent cherry-picking among contemporary expert claims. The "lipid hypothesis" is bad science, he says, but he spends many pages enthusiastically endorsing some just-in findings about how the ratio of omega-6 to omega-3 fatty acids is ruining our health. Here Pollan cannot be writing from the platform of common sense, because he is making substantial and particular claims about specific nutrients and their virtues. (What happened to the blanket criticism of nutritionism?) So some imports from the academic laboratory do, after all, find their way into native common sense, culture and the wisdom of "mom." And that's telling. Even in such soft and vulnerable areas as nutrition, expertise inevitably intrudes into the vernacular.


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