Michael Pollan is a contributing writer at The New York Times Magazine and Knight professor of journalism at the University of California, Berkeley.

Eat food. Not too much. Mostly plants.

That, more or less, is the short answer to the supposedly incredibly complicated and confusing question of what we humans should eat in order to be maximally healthy. I hate to give away the game right here at the beginning of a long essay, and I confess that I'm tempted to complicate matters in the interest of keeping things going for a few thousand more words. I'll try to resist but will go ahead and add a couple more details to flesh out the advice. Like: A little meat won't kill you, though it's better approached as a side dish than as a main. And you're much better off eating whole fresh foods than processed food products. That's what I mean by the recommendation to eat "food." Once, food was all you could eat, but today there are lots of other edible foodlike substances in the supermarket. These novel products of food science often come in packages festooned with health claims, which brings me to a related rule of thumb: if you're concerned about your health, you should probably avoid food products that make health claims. Why? Because a health claim on a food product is a good indication that it's not really food, and food is what you want to eat.

Uh-oh. Things are suddenly sounding a little more complicated, aren't they? Sorry. But that's how it goes as soon as you try to get to the bottom of the whole vexing question of food and health. Before long, a dense cloud bank of confusion moves in. Sooner or later, everything solid you thought you knew about the links between diet and health gets blown away in the gust of the latest study.

Last winter came the news that a low-fat diet, long believed to protect against breast cancer, may do no such thing — this from the monumental, federally financed Women's Health Initiative, which has also found no link between a low-fat diet and rates of coronary disease. The year before we learned that dietary fiber might not, as we had been confidently told, help prevent colon cancer. Just last fall two prestigious studies on omega-3 fats published at the same time presented us with strikingly different conclusions. While the Institute of Medicine stated that "it is uncertain how much these omega-3s contribute to improving health" (and they might do the opposite if you get them from mercury-contaminated fish), a Harvard study declared that simply by eating a couple of servings of fish each week (or by downing enough fish oil), you could cut your risk of dying from a heart attack by more than a third — a stunningly hopeful piece of news. It's no wonder that omega-3 fatty acids are poised to become the oat bran of 2007, as food scientists micro-encapsulate fish oil and algae oil and blast them into such formerly all-terrestrial foods as bread and tortillas, milk and yogurt and cheese, all of which will soon, you can be sure, sprout fishy new health claims. (Remember the rule?)

By now you're probably registering the cognitive dissonance of the supermarket shopper or science-section reader, as well as some nostalgia for the simplicity and solidity of the first few sentences of this essay. Which I'm still prepared to defend against the shifting winds of nutritional science and food-industry marketing. But before I do that, it might be useful to figure out how we arrived at our present state of nutritional confusion and anxiety.

The story of how the most basic questions about what to eat ever got so complicated reveals a great deal about the institutional imperatives of the food industry, nutritional science and — ahem — journalism, three parties that stand to gain much from widespread confusion surrounding what is, after all, the most elemental question an omnivore confronts. Humans deciding what to eat without expert help — something they have been doing with notable success since coming down out of the trees — is seriously unprofitable if you're a food company, distinctly risky if you're a nutritionist and just plain boring if you're a newspaper editor or journalist. (Or, for that matter, an eater. Who wants to hear, yet again, "Eat more fruits and vegetables"?) And so, like a large gray fog, a great Conspiracy of Confusion has gathered around the simplest questions of nutrition — much to the advantage of everybody involved. Except perhaps the ostensible beneficiary of all this nutritional expertise and advice: us, and our health and happiness as eaters.

From Food to Nutrients

It was in the 1980s that food began disappearing from the American supermarket, gradually to be replaced by "nutrients," which are not the same thing. Where once the familiar names of recognizable comestibles — things like eggs or breakfast cereal or cookies — claimed pride of place on the brightly colored packages crowding the aisles, now new terms like "fiber" and "cholesterol" and "saturated fat" rose to large-type prominence. More important than mere foods, the presence or absence of these invisible substances was now generally believed to confer health benefits on their eaters. Foods by comparison were coarse, old-fashioned and decidedly unscientific things — who could say what was in them, really? But nutrients — those chemical compounds and minerals in foods that nutritionists have deemed important to health — gleamed with the promise of scientific certainty; eat more of the right ones, fewer of the wrong, and you would live longer and avoid chronic diseases.

Nutrients themselves had been around, as a concept, since the early 19th century, when the English doctor and chemist William Prout identified what came to be called the "macronutrients": protein, fat and carbohydrates. It was thought that that was pretty much all there was going on in food, until doctors noticed that an adequate supply of the big three did not necessarily keep people nourished. At the end of the 19th century, British doctors were puzzled by the fact that Chinese laborers in the Malay states were dying of a disease called beriberi, which didn't seem to afflict Tamils or native Malays. The mystery was solved when someone pointed out that the Chinese ate "polished," or white, rice, while the others ate rice that hadn't been mechanically milled. A few years later, Casimir Funk, a Polish chemist, discovered the "essential nutrient" in rice husks that protected against beriberi and called it a "vitamine," the first micronutrient. Vitamins brought a kind of glamour to the science of nutrition, and though certain sectors of the population began to eat by its expert lights, it really wasn't until late in the 20th century that nutrients managed to push food aside in the popular imagination of what it means to eat.

No single event marked the shift from eating food to eating nutrients, though in retrospect a little-noticed political dust-up in Washington in 1977 seems to have helped propel American food culture down this dimly lighted path. Responding to an alarming increase in chronic diseases linked to diet — including heart disease, cancer and diabetes — a Senate Select Committee on Nutrition, headed by George McGovern, held hearings on the problem and prepared what by all rights should have been an uncontroversial document called "Dietary Goals for the United States." The committee learned that while rates of coronary heart disease had soared in America since World War II, other cultures that consumed traditional diets based largely on plants had strikingly low rates of chronic disease. Epidemiologists also had observed that in America during the war years, when meat and dairy products were strictly rationed, the rate of heart disease temporarily plummeted.

Naïvely putting two and two together, the committee drafted a straightforward set of dietary guidelines calling on Americans to cut down on red meat and dairy products. Within weeks a firestorm, emanating from the red-meat and dairy industries, engulfed the committee, and Senator McGovern (who had a great many cattle ranchers among his South Dakota constituents) was forced to beat a retreat. The committee's recommendations were hastily rewritten. Plain talk about food — the committee had advised Americans to actually "reduce consumption of meat" — was replaced by artful compromise: "Choose meats, poultry and fish that will reduce saturated-fat intake."

A subtle change in emphasis, you might say, but a world of difference just the same. First, the stark message to "eat less" of a particular food has been deep-sixed; don't look for it ever again in any official U.S. dietary pronouncement. Second, notice how distinctions between entities as different as fish and beef and chicken have collapsed; those three venerable foods, each representing an entirely different taxonomic class, are now lumped together as delivery systems for a single nutrient. Notice too how the new language exonerates the foods themselves; now the culprit is an obscure, invisible, tasteless — and politically unconnected — substance that may or may not lurk in them called "saturated fat."

The linguistic capitulation did nothing to rescue McGovern from his blunder; the very next election, in 1980, the beef lobby helped rusticate the three-term senator, sending an unmistakable warning to anyone who would challenge the American diet, and in particular the big chunk of animal protein sitting in the middle of its plate. Henceforth, government dietary guidelines would shun plain talk about whole foods, each of which has its trade association on Capitol Hill, and would instead arrive clothed in scientific euphemism and speaking of nutrients, entities that few Americans really understood but that lack powerful lobbies in Washington. This was precisely the tack taken by the National Academy of Sciences when it issued its landmark report on diet and cancer in 1982. Organized nutrient by nutrient in a way guaranteed to offend no food group, it codified the official new dietary language. Industry and media followed suit, and terms like polyunsaturated, cholesterol, monounsaturated, carbohydrate, fiber, polyphenols, amino acids and carotenes soon colonized much of the cultural space previously occupied by the tangible substance formerly known as food. The Age of Nutritionism had arrived.

CONTINUED

© 2007 Michael Pollan

Michael Pollan is a contributing writer at The New York Times Magazine, where this essay first appeared, and Knight professor of journalism at the University of California, Berkeley. He is the author of The Botany of Desire: a Plant's-Eye View of the World and The Omnivore's Dilemma, which was chosen by the editors of The New York Times Book Review as one of the 10 best books of 2006.

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