Michael Pollan's just-published book, In Defense of Food: An Eater's Manifesto (Penguin Press, $21.95 cloth), has a placental look: its monumental predecessor, The Omnivore's Dilemma (Penguin Press, 2006), appeared not even two years ago, and at about 200 pages the new volume is slight. But don't be deceived: Defense isn't an afterthought. It makes up in passionate intensity what it lacks in heft, and, page for page, it contains more intellectual and moral nutrition than practically any other book I'm aware of.

If Omnivore was a large conceit, Defense is a potent essay whose subject is, finally, the ways in which food science has misled us into various foolish wars: against fat, against carbs, and on behalf of supplements, to name just a few. With each battle, we eaters of the so-called Western diet — that scientifically produced and not very healthy amalgam of refined flour and sugar, industrially manipulated fats, and grudging sprinkles of monocultural vegetables, fruits, and meats — drift further away from our evolutionary moorings and must depend on yet more science (this time medical) to help right the balance. Great fortunes have already been made in the selling of lousy food to a captive and credulous population that then must pay out another fortune in health care bills. Nice work if you can get it.

Defense certainly rends the veil of infallibility in which contemporary science tends to cloak itself, and in doing so it raises the question of what we mean by "science." The word's pop meaning is clear enough and involves microscopes, centrifuges, supercomputers, and a presidium of authorities in white lab coats. But the word's Latin root means "to know," and Defense convincingly establishes that knowledge is not the exclusive purview of the lab-coat people. "There are more things in Heaven and Earth than are dreamed of in your philosophy, Horatio," Hamlet instructs us, and they won't all surrender their secrets to Horatio's fancy gadgetry. We put ourselves at risk, in fact, when under the rubric of science we set aside millennia of human discoveries and understandings of the world — when we stop eating what we've long eaten, for instance, and open a bag of manufactured quasi food, like Doritos.

Science should be about skepticism, not faith, and perhaps in laboratories it still is. But these days, when it enters the public domain it morphs into something else — something suspiciously like dogma.

Paul Reidinger

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