In our town my favorite store after the Smile a While Bookshop was Morosini’s market with its pyramids of navel oranges from California which seemed to glow within their pink tissue wrappers. Apples, pears, even potatoes wrapped in tissue imprinted with the word “Idaho” were stacked in woven baskets beneath a frieze of pineapple soldiers with crossed swords. I remember the wooden crates of Bibb lettuce under crushed ice, the cloying sweetness of ripe honeydew in August, the yeasty smell of fresh bread, and the sweet, sharp smell of Parmigiano. Beside the cash register were faded sepia prints of Mr. Morosini’s native village, old men in black hats wearing white shirts under tight black suit coats. It was in Morosini’s that I saw my first Red Delicious apple, a new hybrid that lived up to its name until it was manipulated into inanity for the sake of shelf life.

I remember too my dismay edged with fear and anger when the first supermarket opened across the street from Morosini’s. This must have happened in August of 1939 because I conflate this memory with the day my father told me that war was certain if Hitler attacked Poland. He hoped the war would not begin on the 25th, my birthday. But it was not war that worried me. It was the fate of Morosini’s California navels. I was an eleven-year-old isolationist and an elitist. The new supermarket was selling Florida oranges for ten cents a dozen. Mr. Morosini’s navels were ten cents each. I consoled myself that the supermarket would fail, that no one would buy its pallid Florida oranges. But a shadow had fallen across my tissue-wrapped world for I knew even then that Mr. Morosini didn’t stand a chance.

The subject of Michael Pollan’s fine new book, In Defense of Food, is the technological abyss toward which humankind with its tacit consent is being driven by the industrialized American diet. Pollan’s critique of the American food industry and the plague of obesity, diabetes, coronary disease, cancer, and untimely death for which it is largely responsible is comparable to the work of Rachel Carson as a contribution to the history of human self-destruction, for the food fabricators could not have done their work without our complicity any more than the environmental polluters could have done theirs. One might go so far as to say that these calamities are themselves the outcome of a species failure, an evolutionary maladjustment of the human brain implicit in the triumph of ingenuity over wisdom.

What Pollan calls the American diet of refined white flour, polished rice, soy and corn oil, corn sweeteners, and corn-fed animal fats has now rampaged across world markets, upending traditional diets wherever it erects its golden arches. It has done so by extrapolating from their natural settings the essential fats and sugars to which animal appetites instinctively respond and on which human life has always depended, stripping away their inherent complexity and turning processed corn, wheat, and soy into such marketable forms as Wonder Bread, Twinkies, Whoppers, and Chicken McNuggets.

“Per capita fructose consumption has increased 25 percent in the past thirty years,” Pollan writes. The mass production of food for a mass society was of course inevitable, but was it also inevitable, as one nutrition expert put it, that “we’re in the middle of a national experiment in the mainlining of glucose,” the form in which fructose is metabolized in the liver and transmitted by insulin to the cells to be used as energy? We assimilate the complex nutrients of traditional foods slowly, but the rush of refined sugars supplied by our industrialized diet overwhelms the ability of the protein hormone insulin to process it. The result is a sudden jolt of energy and soon a craving for more, as the unused glucose is stored as triglycerides, i.e., fat. “An American born in 2000 has a 1 in 3 chance of developing diabetes in his lifetime,” Pollan writes. “80 percent of diabetics will suffer from heart disease.” This “global pandemic in the making…is well on its way to becoming normalized in the West”"recognized as a whole new demographic and so a major marketing opportunity” for “the various drugs and gadgets for diabetics…dialysis and kidney transplantation.”

The symbiosis of the American food and pharmaceutical industries, to which Pollan refers, is the grotesque avatar of the primitive supermarket that I dreaded on the eve of the Second World War. “Is it just a coincidence,” Pollan asks,

that as the portion of our income spent on food has declined, spending on health care has soared? In 1960 Americans spent 17.5 percent of their income on food and 5.2 percent…on health care. Since then, those numbers have flipped: Spending on food has fallen to 9.9 percent, while spending on health care has climbed to 16 percent of national income.

Pollan describes a telling experiment:

In the summer of 1982, a group of ten middle-aged, overweight, and diabetic Aborigines living… near the town of Derby, Western Australia, agreed to participate in an experiment to see if temporarily reversing the process of westernization they had undergone might also reverse their health problems. Since leaving the bush some ten years before, all ten had developed type 2 diabetes; they also showed signs of insulin resistance …and elevated levels of triglycerides in the blood”"a risk factor for heart disease.

“Metabolic syndrome,” or “syndrome X,” is the medical term for the complex of health problems these Aborigines had developed: Large amounts of refined carbohydrates in the diet combined with a sedentary lifestyle had disordered the intricate (and still imperfectly understood) system by which the insulin hormone regulates the metabolism of carbohydrates and fats in the body.

Metabolic syndrome has been implicated not only in the development of type 2 diabetes, but also in obesity, hypertension, heart disease, and possibly certain cancers. Some researchers believe that metabolic syndrome may be at the root of many of the “diseases of civilization” that typically follow a native population’s adoption of a Western lifestyle and the nutrition transition that typically entails.

The ten Aborigines agreed to return to their traditional homeland, “more than a day’s drive by off-road vehicle from the nearest town,” where they had “no access to store food or beverages.” Accompanied by the nutrition researcher who designed the experiment, the Aborigines during their seven-week stay relied “exclusively on foods they hunted and gathered themselves…seafood, supplemented by birds, kangaroo, and…the fatty larvae of a local insect.” Moving inland to a riverbank the Aborigines expanded their diets “to include turtle, crocodile,…yams, figs, and bush honey.”

Their civilized diet had consisted mainly of “‘flour, sugar, rice, carbonated drinks, alcoholic beverages (beer and port), powdered milk, cheap fatty meat, potatoes, onions, and [some] fruits and vegetables’”"the local version of the Western diet.” After seven weeks the Aborigines had lost on average 17.9 pounds and their blood pressure had dropped. Their triglycerides had fallen to within normal range and “all of the metabolic abnormalities of type II diabetes were either greatly improved…or completely normalized…by [their] relatively short… reversion to traditional hunter-gatherer lifestyle.”

“The human animal,” Pollan writes, “is adapted to, and apparently can thrive on, an extraordinary range of different diets, but the Western diet, however you define it, does not seem to be one of them.” But few of us can retreat to pre-industrial habitats and only the rich can afford spas and fat farms. For the poor even the Whole Foods Market and the seasonal farmers’ markets are beyond their reach. Yet we are not helpless against what Pollan calls the endemic “diseases of civilization.” These arise directly from “highly processed foods and refined grains; the use of chemicals to raise plants and animals in huge monocultures; the superabundance of cheap calories of sugar and fat produced by modern agriculture; and the narrowing of…biological diversity…to a tiny handful of staple crops, notably wheat, corn, and soy” that supply our diet. But the Aboriginal experiment shows that the damage to individuals and even to the habitat itself is reversible.

Though Pollan has not written a diet book in the usual sense, his aim is to show how this reversal can be accomplished. His advice is deceptively simple: “Eat food. Not too much. Mostly plants.” This is not as easy as it sounds, especially for those too poor, too busy, or otherwise distracted to follow Pollan’s advice or even to admit that their lives depend upon it. But one piece of advice is available to everyone: avoid all foods packaged with long lists of ingredients, especially those whose names cannot be pronounced. For example, the list of ingredients in Sara Lee’s Soft & Smooth Whole Grain White [sic] Bread occupies half a page of Pollan’s book and includes beside the omnipresent high-fructose corn syrup such wonders as ethoxylated mono- and diglycerides, azodicarbonamide, and guar gum. By contrast, a ciabatta loaf from my local bakery lists only unbleached wheat flour, durum flour, water, starter, salt, diastatic barley malt, and yeast, all of which, except the malt and starter, can be found in my own pantry.

First, however, it is important to know how this great dietary transformation took place. In his previous book, The Omnivore’s Dilemma,[*] Pollan visits a sustainable farm near Charlottesville, Virginia, a remarkable experiment in self-regulating, small-scale agriculture in which the farm family and its cattle, hogs, poultry, and grass flourish in symbiotic harmony without agricultural chemicals or antibiotics and only minimal amounts of processed feed. But sustainable farming is not sustainable on a national scale any more than Alice Waters can cook for the entire United States or an Aboriginal diet of insect larvae and crocodile can feed Australia. A vast industrial organism extends from the United States Department of Agriculture to nutritionist laboratories to cornfields to feed lots to test kitchens to Super Bowl commercials to supermarkets to obesity and untimely death. This entire process has become our second nature.

Pollan is not a Luddite. The problem is not the existence of a mass feeding industry but its ethics, for the purveyors of our high-fructose and glucose diet must know by now that Americans are sickened by their products just as surely as the tobacco promoters know the terrible risk they are urging smokers to take. The organic movement now largely co-opted by the food industry offers a partial solution at somewhat higher cost but, as Pollan writes, though “the superiority of real food grown in healthy soils seems clear…it makes no difference to your metabolism if the high-fructose corn syrup in your soda is organic.” The burden, in other words, is on the consumer but the structure of American agro-industry makes self-preservation difficult.

The industrialization of the food supply is, of course, inseparable from industrialization itself, but it assumed its present dangerous character in the mid-1970s when in response to a “spike in food prices [which] brought protesting housewives into the street… the Nixon administration…adopt[ed] an ambitious cheap food policy” to produce and sell “large quantities of calories as cheaply as possible.” Since the 1930s federal subsidies had encouraged farmers to limit production in order to maintain stable prices: what its New Deal sponsors called the Ever-Normal Granary. But now “agricultural policies [have been] rewritten to encourage farmers to plant crops like corn, soy, and wheat fencerow to fencerow,” driving production up and prices down:

Since 1980, American farmers have produced an average of 600 more calories per person per day, the price of food has fallen, portion sizes have ballooned, and… we’re eating…at least 300 more calories a day than we consumed in 1985…. Nearly a quarter of these additional calories come from added sugars (and most of that in the form of high-fructose corn syrup); roughly another quarter from added fat (most of it in the form of soybean oil); 46 percent from grains (mostly refined)…. The overwhelming majority of [these added calories] supply lots of energy but very little of anything else.

As a result Americans are “both overfed and undernourished.”

This radical change resulted in large part from a decision by Earl Butz, Nixon’s secretary of agriculture and a champion of large-scale “fencerow to fencerow” farming, to dismantle New Deal farm policy and its subsidized crop limits and install a new system to encourage farmers to maximize production while the government made up the shortfall between its “target price” and the much-reduced market price by direct payments to farmers per bushel. The more a farmer produced, the more he would be paid.

By depressing farm prices through overproduction Butz was subsidizing not only the growers but agribusiness and the food manufacturers so that now all parties were growing fat on Butz’s cheap grains”"Archer Daniels Midland, Cargill, General Foods, beef cattle in their feed lots, and the American consumer. The exceptions were marginal farmers in poor countries who were devastated by cheap American exports.

But this was not the only sin perpetrated in the 1970s. Another was the result of a controversy aroused in 1977 by the Select Senate Committee on Nutrition and Human Needs chaired by George McGovern that advised Americans for the sake of their health to eat less meat and fewer dairy products. When cattle ranchers, including Senator McGovern’s own South Dakota constituents, objected angrily, the unnerved committee responded by a subtle change in language from “reduce consumption of meat” to “choose meats, poultry, and fish that will reduce saturated fat intake.”

Hereafter government warnings would be addressed not to foods themselves but to ingredients. The result, according to Pollan, was the deluge of ingredients that were added by food marketers to promote their denatured product. The problem, Pollan points out, is not that these additives are worthless but that they are extracted from their natural origins and may not have the intended effect. “The problem with nutrient-by-nutrient nutrition science,” according to Marion Nestle, a New York University nutritionist, “is that it takes the nutrient out of the context of the food, the food out of the context of the diet, and the diet out of the context of the lifestyle.” The nutritionists hired by food manufacturers to enhance and promote their refined grains face a problem familiar to economists: an abundance of complex variables, including the vagaries of human nature, that make forecasting highly problematic. Pollan goes further:

The uncomfortable fact is that the entire field of nutritional science rests on a foundation of ignorance and lies about the most basic question of nutrition: What are people eating?

Pollan tested this claim over lunch with Dr. Nestle, asking if he was “perhaps being too harsh.” She smiled and replied,

To really know what a person is eating you’d have to have a second invisible person following [him] around, taking photographs, looking at ingredients, and consulting accurate food composition tables, which we don’t have….

It’s impossible. Are people unconsciously underestimating consumption of things they think the researcher thinks are bad or overestimating consumption of things the researcher thinks are good? We don’t know. Probably both. The issue of reporting is extraordinarily serious. We have to ask, How accurate are the data?

Another leading nutritionist, Professor Gladys Block, nearing retirement at Berkeley and the designer of the Food Frequency Questionnaires on which the Womens’ Health Initiative based its survey, goes further: “It’s a mess…. I don’t believe anything I read in nutritional epidemiology anymore. I’m so skeptical at this point.” Pollan concludes that

thirty years of nutritional advice have left us fatter, sicker, and more poorly nourished. Which is why we find ourselves in the predicament we do: in need of a whole new way to think about eating.

The best way to learn this new way is to read Pollan’s new book and then its predecessor, his wonderful Omnivore’s Dilemma. I have done that and in two weeks have lost eight pounds and feel fine. You will too.

Pollan knows this subject well, having scrutinised modern food choices in his magisterial The Omnivore’s Dilemma. Here he is concerned that we are in the clutches of an industry using food scientists to legitimise its most profitable products. We must escape, before we all succumb to the condition of orthorexia, an unhealthy obsession with healthy eating. As he points out, healthy food has become a national preoccupation in the US, but at the same time, two-thirds of the population are overweight.

Pollan’s prescription for this social illness is pithy: “Eat food. Not too much. Mostly plants.” By “food” he means real, whole food, not the processed “foodlike substances” that dominate supermarkets. His elaboration on these strictures can be comically blunt: “Avoid foods that make health claims,” he says; first because they are sold in packets (a bad sign); but second because nutritional warnings can be misleading. Margarine, for example, was recommended until recently because it had less saturated fat than butter. Yet trials have failed to find a clear link between saturated fat and heart disease.

The solution, Pollan argues, is to revert to traditional foods: “Don’t eat anything that your great-grandmother wouldn’t recognise as food.” Some will regard this notion as rose-tinted, but Pollan is persuasive.

The book’s argument gets more contentious with Pollan’s claim that what is good for one’s health also tends to be better for the planet. It is true that cutting down on meat would reduce the livestock industry’s contribution to water shortages. Less conveniently however, governments, including Britain’s, have advised people to eat two portions of fish a week–despite over-exploiting rivers and oceans.

In this slight volume, which is really a postscript to The Omnivore’s Dilemma, there is insufficient room to thrash out the tense relation between personal wellbeing and environmental responsibility. But with his lucid style and innovative research, Pollan deserves his reputation as one of the most respectable voices in the modern debate about food.

“The Omnivore’s Dilemma,” his last book, targeted corn, and its perniciously processed derivative high-fructose corn syrup, as the culprit responsible for a lot of what’s wrong with food production and consumption in this country. Now he’s back with “In Defense of Food: An Eater’s Manifesto” (Penguin, 231 pp., $21.95), a brisk new volume that probes deep–literally–into our bulging stomachs and congested veins to analyze what the stuff we ingest is actually made of, how it came to be so chemically complex and what we can do about it.

Pollan’s bugbear this time is the so-called science of nutrition. Back in the good old days, people ate plants and animals raised (or foraged) close to (or at) home and prepared accordingly to age-old traditions. But once nutritionists started isolating the chemical components of what we ate and putting them back to together in “new, improved” and highly processed ways, Americans began growing steadily more obese, more prone to diabetes, cancer and heart disease, and more stressed about our dietary options. These days our food is cheap, convenient and increasingly plastered with health claims–but it’s making us and everyone else who eats it fat and sick.

It’s not just that “nutritionism” is imprecise, confusing and constantly changing its mind–remember when margarine was healthier than butter and no one knew what trans-fats or Omega 3s were? In Pollan’s view, the very idea of approaching food as “a matter of biology” is dead wrong. The evidence speaks for itself. The “Western diet” engineered by nutritionists, food industry executives, advertisers and journalists has ushered in something new under the sun: “the human being who manages to be both overfed and undernourished.”

Pollan wants to put a stop to this first by exposing how and why it happened, then by helping us “reclaim our health and happiness as eaters.” So this time, he jumps the fence from reporting to preaching, guiding us through the supermarket (or better yet farmers market), the kitchen and the dining room. His advice, grounded in common sense and folk wisdom, strikes this eater as eminently sound: never eat anything your great grandmother would not have recognized as food; avoid anything with more than five ingredients; eat more plants than animals and more leaves than seeds; grow your own whenever possible.

“In Defense of Food” is written with Pollan’s customary bite, ringing clarity and brilliance at connecting the dots. If the book is not quite as engrossing as “The Omnivore’s Dilemma,” it’s because fats, carbs and calories simply do not offer the narrative possibilities of hunting a pig or following a steer from prairie to feedlot.

As the Senate’s recent rubber-stamping of yet another pork-filled farm bill demonstrates, America still lacks the political will to reform the agricultural practices at the root of our dietary woes. But to Pollan, that’s no reason why enlightened eaters can’t rise up and start changing the Western diet one meal, one garden, one family farm at time. At heart, this mild-mannered journalist-gardener is not only a crusader but a revolutionary. More power to him, I say.

“Why don’t we do that?” she asked.

Pollan’s previous book, “The Omnivore’s Dilemma,” led readers through the levels of American food hell (feedlots, monoculture, McDonald’s drive-throughs, organic produce shipped from Chile). As I made my way through it recently, I shared its ethical challenges with my spouse.

“Then what are we supposed to eat?” she finally asked.

“In Defense of Food” is Pollan’s answer, the needle through which we must squeeze our fatted high-fructose selves to find salvation. But first, how we got here.

“Here” is the end-product of our industrialized Western diet. Cancer, cardiovascular diseases, diabetes and obesity can all be directly linked to “the rise of highly processed foods and refined grains; the use of chemicals to raise plants and animals in huge monocultures; the superabundance of cheap calories of sugar and fat produced by modern agriculture; and the narrowing of the biological diversity of the human diet to a tiny handful of staple crops, notably wheat, corn, and soy,” writes Pollan.

Pollan dishes up plenty of blame: the food industry’s $32 billion annual marketing effort; science’s endless nutrient debate, in which the sum of parts never quite equals a whole food diet; the government, with its politically motivated and industry-driven standards; and the journalists who herald every new silver-bullet tonic.

The business of food is adding value to raw ingredients. With the help of farm subsidies, it’s no wonder that two-thirds of our daily caloric intake comes from corn, soy, wheat and rice. Since 1980, Pollan says, sweeteners and added fats have gotten 20 percent cheaper, while fresh fruits and vegetables — products that have, incidentally, lost nutritional value over the past half-century — cost 40 percent more.

And it’s the triumph of misguided food science over food culture that has enabled much of this descent. The belief that the human body’s food needs could be broken down into fats, proteins and carbs, then further broken down into subsets of each, loses sight of the food for the nutrients, says Pollan.

Thirty-five different antioxidants have been identified in thyme. Olive oil improves the body’s use of lycopene in tomatoes. So much of what comes from eating real food, versus food products, takes care of us naturally, without scientific intervention. “You don’t need to fathom a carrot’s complexity in order to reap its benefits,” he writes. And so, the suggestions:

Don’t eat anything your great-grandmother wouldn’t recognize. Avoid products that make health claims. Shop the peripheries of supermarkets, where the real food is, rather than the center aisles. Or skip the grocery and hit the farmers markets. Have a glass of wine. Eat plants, especially the leaves. Spend a little more and eat a little less. Plant a garden. Cook. Eat meals, at a table, together.

Forty years ago, Pollan says, eating this way would have amounted to a crackpot’s manifesto. Today, with the proliferation of fresh, local, real food, we may have excuses — but no excuse.

In the hundreds of interviews Pollan gave following the book’s publication, the question everyone, including me, asked him was: What do you eat? It was both a sincere attempt to elicit a commonsense prescription and, when it came from cynical East Coast journalists, a thinly veiled attempt to trap the author. “Oh! So he shops at farmers markets,” we snipped enviously to one another. “Well, easy for him out there in Berkeley where they feast on peaches and cream in February! What about the rest of us?”

In Defense of Food is Pollan’s answer: “Eat food. Not too much. Mostly plants.”

For some, that instruction will seem simple, even obvious. (It will seem especially so to those who read Pollan’s lengthy essay on the same topic in the New York Times magazine last year.) But for most people, those seven little words are a declaration of war on the all-American dinner. Goodbye, 12-ounce steak. Instead, how about three ounces of wild-caught salmon served with roasted butternut squash and a heap of sauteed kale? For many, following the rules may not be so simple after all.

Yet in this slim, remarkable volume, Pollan builds a convincing case not only against that steak dinner but against the entire Western diet. Over the last half-century, Pollan argues, real food has started to disappear, replaced by processed foods designed to include nutrients. Those component parts, he says, are understood only by scientists and exploited by food marketers who thrive on introducing new products that hawk fiber, omega-3 fatty acids or whatever else happens to be in vogue.

Pollan calls it the age of “nutritionism,” an era when nutrients have been elevated to ideology, resulting in epidemic rates of obesity, disease and orthorexia, a not yet official name for an unhealthy obsession with healthy eating. “What we know is that people who eat the way we do in the West today suffer substantially higher rates of cancer, cardiovascular diseases, diabetes, and obesity than people eating any number of different traditional diets,” he writes. “When people come to the West and adopt our way of eating, these diseases soon follow.”

Part of Pollan’s answer to improving our health is going back to traditional foods and ways of eating: Eat leaves, not seeds. Steer clear of any processed food with a health claim. And for goodness sake, don’t eat anything your grandmother wouldn’t recognize as food.

But equally important is changing the way we relate to food. Pollan argues that we’ve traded in our food culture — a.k.a. eating what Mom says to eat — for nutritionism, which puts experts in charge and makes the whole question of what to eat so confusing in the first place. Indeed, Pollan makes a strong case that the “French paradox” — the way the French stay thin while gobbling triple creme cheese and foie gras — isn’t a paradox at all. The French have a different relationship with food. They eat small portions, don’t come back for seconds and spend considerably more time enjoying their food — an eminently sensible approach.

In Pollan’s mind, trading quantity for quality and artificial nutrients for foods that give pleasure is the first step in redefining the way we think about food. The rules here: Pay more, eat less. Eat meals, not snacks. Cook your own meals and, if you can, plant a garden.

Each of the rules is well supported — and only occasionally with the scientific mumbo-jumbo that Pollan disparages. But what makes Pollan’s latest so engrossing is his tone: curious and patient as he explains the flaws in epidemiological studies that have buttressed nutritionism for 30 years, and entirely without condescension as he offers those prescriptions Americans so desperately crave.

That’s no easy feat in a book of this kind. What should we eat? The answer is here. Now we just have to see if Americans are willing to follow good advice.

His personal narrative of four different “American” meals and the unique journey each ingredient took to get to his plate has received numerous awards and accolades, but I was left feeling a little unsatisfied. Despite all of this new information, I still don’t have an answer to my most fundamental question: What should I eat for dinner tonight?

Here is Pollan’s brilliant, succinct and nuanced answer to this question:

“Eat food. Not too much. Mostly plants.”

Pollan elaborates, but that summary turns out to be remarkably complete.

One can argue that Pollan isn’t telling us anything we didn’t already know. Presumably we at least suspected that if, as he advises, we grew some of our own food, bought the rest at farmers markets, eliminated all foods with high-fructose corn syrup and cooked almost all of our food from scratch, we would live remarkably healthy lives.

The obviousness of this advice is part of the point. He claims only “the authority of tradition and common sense.” So why do we need Pollan to remind us of something so simple that it can be summarized in seven words?

Well, because we do.

Pollan laments that “thirty years of nutritional advice have left us fatter, sicker, and more poorly nourished.” That is why Pollan spends a large portion of this book exploring not what we ought to eat, but how we got to the state where we are desperate for a new answer to that question.

For thousands of years humans ate food prepared by one source — their mothers. Then along came the science of nutrition, and the rise of “nutritionism,” a term Pollan borrows for describing a belief system that assumes “that the key to understanding food is … the nutrient.”

Suddenly food was a complicated subject. Your mother could not possibly know what you should eat, unless your mother also happened to have a degree in nutritional science.

We stopped thinking about eating as an activity that could make us more or less happy, and instead saw only the connection between the nutrients we ingest and a reductionist concept of physical health.

Examining the history of nutritional advice over the past hundred years or so reveals a kind of war between nutrients, as each one in turn takes the blame for our ills.

Fat, the most recent villain, is making a comeback as a positive food, and carbohydrates are poised to become the arch-nemesis of 21st-century nutritionists.

He references, and for the most part supports, the work of Gary Taubes, including his recent book, “Good Calories, Bad Calories.” But he disagrees with the idea that fear of fat should be replaced with a fear of carbohydrates. That’s just nutritionism all over again.

Pollan’s simple rules might seem complicated to us, because in order to understand them, we need to un-learn the rules of nutritionism. Here are some of the highlights:

- Eat food. What is food? Food is that which your great-grandmother would recognize as food. That means no “go-gurt,” no “meal substitutes,” no “protein shakes.”

- When you’re in the supermarket, “avoid food products containing ingredients that are a) unfamiliar, b) unpronounceable, c) more than five in number, or that include d) high-fructose corn syrup.”

- Eat mostly plants. Think of meat as a side dish or garnish rather than the principal component of the meal. Eat wild plants when you can.

- Eat less. Spend more — more money and more time.

It turns out that finding food is not necessarily that easy. We may not have to hunt and forage, but it can begin to seem like that. The best ways to find food are to get out of the supermarket and into farmers markets, community-supported agriculture and your own garden.

There is an inescapably elitist component to this argument, which Pollan acknowledges. Not everyone can afford to spend more money and time on food, yet, he’s adamant about the responsibility of those of us who can spend more to do so.

When a book like this comes along, people tend to embrace it as the gospel truth — and in a lot of ways it is. Pollan’s advice is revelatory. No more counting calories, or vitamins, or desperately trying to remember the different between Omega-3 and Omega-6 fats.

Unfortunately, there is one fairly obvious problem with this advice: Americans don’t primarily eat food that comes in a box with a long list of “health claims” because they actually think they’re healthier than a home-cooked meal. We do so because we are addicted — to high-fructose corn syrup, soda pop, cookies, fast food and takeout.

Turns out the new story sounds a lot like the old. There is no silver bullet for changing our lifestyles and improving our health. It takes commitment, hard work and a certain amount of self-denial.

But part of what Pollan says really is new, despite also being incredibly old. Changing our national diet doesn’t have to be a story of denial. In the end it can be a story about reclaiming the pleasures of eating and taking control of our own tables.

“You don’t need to spend much time in an American supermarket to figure out that this is a food system organized around the objective of selling large quantities of calories as cheaply as possible,” Pollan declares. Indeed, the word “food,” he explains, is no longer merely the definition for anything we put into our mouths at mealtimes: most items on supermarket shelves are not food at all, but imitations of food. Because of a crafty loophole in FDA regulations, they aren’t required to be labeled as such, and so we are fooled into thinking a “nutritious” sugar cereal with added vitamins and minerals is as good for us as plain oatmeal. Really it’s an alarming amalgam of chemicals, preservatives and derivatives of cheap grains: corn, soy, wheat and rice, the cornerstones of Agribusiness.

Pollan lays bare with impassioned but clear-eyed intelligence the sinister machinations of the contemporary American food industry, the corporate greed that fuels the prevalence of these “food products,” and the systematic stripping of nutrients from our soil and species variety from supermarket shelves in the interest of maximizing yield and profit. He also presents a convincing hypothesis for explaining both the obesity epidemic and the prevalence of “Western diseases,” i.e. diabetes, heart disease and cancer: the shift from leaves to seeds in the modern American diet. That, “helps to account for the flood of refined carbohydrates in the modern diet and the drought of so many micronutrients and the surfeit of total calories. From leaves to seeds: It’s almost, but not quite, a Theory of Everything.”

But Pollan isn’t histrionic or fatalistic. He isn’t setting out to make us feel hopeless, he’s trying to show what’s wrong in order to give us the knowledge we need to fix it. A resident of Berkeley, Calif., Pollan is firmly in the Alice Waters camp: those who can afford it (and he is admirably realistic about the fact that not everyone can) should buy and eat locally-grown produce, supporting farmers who farm in ways that don’t deplete the soil, because doing so helps everyone in the long run. “Yes, shopping this way takes more money and effort, but as soon as you begin to treat that expenditure not just as shopping but also as a kind of vote – a vote for health in the largest sense – food no longer seems like the smartest place to economize.”

Pollan delves into various traditional ways of eating, as varied as Italian, Japanese, French and Greek. These ancient, conventional ways of eating, different as they are, all involve real food, combined and cooked in traditional ways, eaten slowly and enjoyed at a table, often with moderate amounts of alcohol, and (this seems to be key) with other people, socially, convivially. “The point,” he writes, “is to make sure that we don’t eat thoughtlessly or hurriedly, and that knowledge and gratitude will inflect our pleasures at the table.”

This is an important book, short but pithy, and, like the word “food,” not simple at all.

In the same spirit, nutritionism has lately helped to justify vitamin-enriched Diet Coke, bread bolstered with the Omega-3 fatty acids more readily found in fish oil, and many other new improvements on what Michael Pollan calls “the tangible material formerly known as food.”

Goaded by “the silence of the yams,” Mr. Pollan wants to help old-fashioned edibles fight back. So he has written “In Defense of Food,” a tough, witty, cogent rebuttal to the proposition that food can be reduced to its nutritional components without the loss of something essential. “We know how to break down a kernel of corn or grain of wheat into its chemical parts, but we have no idea how to put it back together again,” he writes.

In this lively, invaluable book–which grew out of an essay Mr. Pollan wrote for The New York Times Magazine, for which he is a contributing writer–he assails some of the most fundamental tenets of nutritionism: that food is simply the sum of its parts, that the effects of individual nutrients can be scientifically measured, that the primary purpose of eating is to maintain health, and that eating requires expert advice. Experts, he says, often do a better job of muddying these issues than of shedding light on them. And it serves their own purposes to create confusion. In his opinion the industry-financed branch of nutritional science is “remarkably reliable in its ability to find a health benefit in whatever food it has been commissioned to study.”

Some of this reasoning turned up in Mr. Pollan’s best-selling “Omnivore’s Dilemma.” But “In Defense of Food” is a simpler, blunter and more pragmatic book, one that really lives up to the “manifesto” in its subtitle. Although he is not in the business of dispensing self-help rules, he incorporates a few McNuggets of plain-spoken advice: Don’t eat things that your great-grandmother wouldn’t recognize. Avoid anything that trumpets the word “healthy.” Be as vitamin-conscious as the person who takes supplements, but don’t actually take them. And in the soon to be exhaustively quoted words on the book’s cover: “Eat food. Not too much. Mostly plants.” An inspiring head of lettuce is the poster image for this mantra.

Do we really need such elementary advice? Well, two-thirds of the way through his argument Mr. Pollan points out something irrefutable. “You would not have bought this book and read this far into it if your food culture was intact and healthy,” he says. Nor would you eat substances like Go-Gurt, eat them on the run or eat them at mealtimes that are so out of sync with friends and relatives that the real family dinner is an endangered ritual. Other writers on food, from Barbara Kingsolver to Marion Nestle, have expressed the same alarm, but “In Defense of Food” is an especially succinct and helpful summary.

Among the historical details that underscore a sense of food’s downhill slide: the way a Senate Select Committee led by George McGovern was pressured in 1977 to reword a dietary recommendation. Its warning to “reduce consumption of meat” turned into “choose meats, poultry and fish that will reduce saturated fat intake.”

When Mr. McGovern lost his seat three years later, Mr. Pollan says, the beef lobby “succeeded in rusticating 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 squatting in the middle of its plate.”

Mr. Pollan shows how the story of nutritionism is “a history of macronutrients at war.” If the conventional scientific wisdom has moved from demon (saturated fat) to demon (carbohydrates), creating irreconcilably different theories about the health benefits of various foods, it has also created an up-and-coming eating disorder: orthorexia.

“We are,” he underscores, “people with an unhealthy obsession with healthy eating.” This book is biliously entertaining about orthorexia’s crazy extremes. A recent “qualified” F.D.A.-approved health claim for corn oil makes sense, Mr. Pollan says, “as long as it replaces a comparable amount of, say, poison in your diet and doesn’t increase the total number of calories you eat in a day.”

Since a Western diet conducive to diabetes has led us not to improved eating habits but to a growing diabetes industry, complete with its own magazine (Diabetic Living), Mr. Pollan finds little wisdom from the medical establishment about food and its ramifications. “We’ll know this has changed when doctors have kicked the fast-food franchises out of the hospitals,” he says.

Until then he recommends that we pay more attention to the reductive effects of food science, recognize the fallibility of research studies (because to replicate the healthy effects of, say, the Mediterranean diet completely, you need to live like a villager on Crete) and dial back the clock. Mr. Pollan advocates a return to the local and the basic, even at the risk of elitism. He recommends that Americans spend more on food: not only more money but also more time. Eat less, and maybe you make up the financial difference. Trade fast food for cooking, and maybe you restore some civility to the traditional idea of the meal.

“No, a desk is not a table,” he points out. Though he shouldn’t have to tell us that, readers of “In Defense of Food” will be glad he did.

Pollan’s conclusions align so completely with the approach to food for which Portland is known that actually reading the book might seem unnecessary. After all, we’re already aware of the benefits of eating fresh, local food–in a town that practically coined the term “farm to table,” these concepts are hardly revelatory.

Pollan builds his case systematically, beginning with a societal shift in the last century toward “nutritionist” thinking (i.e., the idea that foods themselves are less important than the nutrients they contain). Drawing from numerous examples of botched nutrition science (remember when margarine was a health food?), Pollan argues that by removing nutrients from foods, and removing foods from their natural ecosystems, we fundamentally distort our relationship to the things that we eat.

By the end of the book, he has constructed a solid intellectual framework for an intuitively sensible approach to eating: the idea that foods are a system, full of complex components that interact in ways that scientists barely understand, and that the best way to attain the maximum health benefit from what you consume is not by eating “low-fat,” “low-carb,” or “fortified” processed foods, but by eating the whole foods from which the human animal has obtained the necessary nutrients for thousands of years.

Pollan’s tone throughout makes the book a fast, entertaining read: He’s exasperated that he has to say this stuff at all, and bemused that political machinations and a blinkered scientific community have so distorted the way Americans eat that good old-fashioned food needs defending. But it does, and it’s a good thing we have Pollan around do it.

We’re sitting outside the original location of Peet’s Coffee, Tea and Spices, on the corner of Vine and Walnut streets in Berkeley, Calif. Peet’s has scores of locations all over the Bay Area, but this one was opened in the late Sixties by a Dutch immigrant who believed “there must be something better” than the Folger’s coffee Americans were drinking. The guys who started Starbuck’s were, by their own admission, imitating Peet’s.

Down the hill is Chez Panisse, the storied restaurant opened by Alice Waters in 1971. More than any other joint in America, Panisse celebrates and symbolizes the idea of linking farms, especially small organic farms, to the experience of fine dining, in what Waters described as The Delicious Revolution. Nearby is the Cheese Board Collective, a famous worker-owned bakery, cheese shop and pizzeria founded in 1967.

But maybe more significant is what’s across the street, a Mission-style Mormon Church and a brown-shingled Quaker Meeting House, because Pollan says he’s really calling for, hoping for the dietary equivalent of the Protestant Reformation. That’s the argument he makes in his new book “In Defense of Food An Eater’s Manifesto” (Penguin, $21.95).

“In the same sense that the Reformation reflected a belief that the way to heaven was through Christ, not through the institution of a single Church, the idea is to let people seek their own dietary salvation,” he says. “There are many denominations of food and dining.”

If you extend the analogy, Pollan is its Martin Luther, nailing his theses to the corporate doors of the American food industry. He has boiled down the thrust of his argument to seven words. “Eat Food. Not Too Much. Mostly Plants.” (Actually, Luther suffered from terrible constipation for most of his life. Pollan’s book might have spared him considerable agony.)

I tell Pollan that, ever since reading his book, I’ve been playing a little mealtime game called “WWMPE.”

He looked puzzled.

“What Would Michael Pollan Eat,” I explain.

He breaks into a wide, somewhat abashed smile.

“That makes me feel odd. I feel like I’m imposing myself on people,” he says.

But then, he is.

This is Pollan’s first prescriptive book, the first time he has dropped the pretext of being just a reporter of other people’s ideas or a transcriber of experiences, the first time he has mainly argued a series of points. The book is short and compact; and, although there’s still good bit of reporting, especially about the history of nutrition science, the book seems designed to be what it says it is: a manifesto a declaration of principles that you carry around and use to remind yourself of certain ideas or to start arguments.

“I’ve never written a book before that you could read in one sitting,” he says.

And yet, Pollan seems a little too self-effacing to step into the tank treads of Mao and Marx and Tom Hayden’s Port Huron Statement. In person, he surprises you with his warmth and his openness, which is just a little bit at variance with the intellectual rigor and serious sense of purpose that pervades his work.

“The change is going to happen with or without me,” he says. “Our current way of producing food can’t go on forever, because it’s destroying the system on which it depends.”

The way almonds are grown, says Pollan, may be responsible for the phenomenon of “colony collapse” — the sudden mass disappearances of bees. New studies point to a connection between the heavy use of antibiotics in livestock — especially pork — and the emergence of drug-resistant staph strains, commonly known as MRSA. As that kind of catastrophic evidence piles up, we will shift back to a more sensible, traditional, diverse method of producing food, he says.

For a decade, he lived in Cornwall, Conn., and wrote extensively about his home and garden there. In the summer of 2003, Pollan and his family moved to the Bay Area where he holds a prestigious journalism professorship at UC-Berkeley.

His 2006 book, “The Ominvore’s Dilemma,” named one of the top 10 books of the year by the New York Times, analyzed four different American meals and questioned the means by which the foods for each were produced. The book vaulted Pollan into the front ranks of the movement criticizing American food production, and it put him into an extended dialogue with readers who were troubled by, among other things, his contention that some of the “industrially” produced organic foods produced on mega-farms and sold at places like Whole Foods weren’t all that much better than their non-organic counterparts.

“In my conversations with readers, I was getting a lot of feedback that said, basically, ‘I’m afraid there won’t be anything I can eat.’ I was somewhat alarmed that my readers would starve to death, which is not a good thing for an author,” Pollan said. “They were taking the information in that book and worrying themselves with it.”

“In Defense of Food” encourages people to ignore — or at least distrust — nutrition science and food fads that caution us to rid our diets of, for example, fat. You’re better off making a leap of faith in the direction of pleasure and tradition, Pollan argues. Eat slower. Pay a little more for the ingredients. Don’t buy packaged foods that make health claims about themselves. Grow them yourself or buy them at farmers’ market. Cook them yourself. Eat them at a table. Eat things that your grandmother would recognize as food. It’s the relationship with food, not the chemistry, that will save you, he writes.

Pollan says a friend compared the book to Benjamin Spock’s 1946 “Baby and Child Care,” although Pollan hastens to add he doesn’t rank himself with Dr. Spock.

“In the 1950s and ’60s, there was this culture of scientific expertise about children’s health, and Dr. Spock basically said ‘Trust your instincts,’” Pollan explains.

His message is similar. Nutrition science has gotten wrong a lot of things that common sense and the traditional wisdom of families used to get right, he says. “Nutritional science is kind of where surgery was in 1650 — really interesting, but do you want to participate directly?” he asks.

“Eat food” might seem like a piece of unnecessary advice, but Pollan actually spends 14 pages defining the word “food.” That such a task is necessary, he writes, shows how far we have drifted from our natural relationship to what we eat. We buy a lot of food that is processed, refined and engineered. Its ingredient lists are full of undecipherable chemical terms and spurious health claims.

“Not Too Much” includes the encouragement to eat actual meals, at a table. Pollan argues that dining has been stripped of its ceremony and has been replaced by a lot snacking and thoughtless noshing. One of his interesting side points is that the multi-billion-dollar food industry sold Americans on the idea that foods could be engineered so that we can continue to eat insane amounts of them, rather than just cutting back a little and concentrating on comestibles that don’t have to be tweaked in laboratories.

“Mostly plants.” That one is pretty self-explanatory, but it’s worth noting that Pollan is not a vegetarian. He hunted a boar for food while writing “The Omnivore’s Dilemma.”

“I’m not the kind of guy you want out in the woods with a gun,” he says, grinning. “But I’m all in favor of hunters. I think hunters know things about food and nature that most of us have forgotten.”

In conversation, he can grow downright rhapsodic about grass-fed beef or pastured eggs.

What kind of eggs?

“The chickens are rotationally grazed,” he explained. “They’re on grass, and the farmer moves them, periodically, to a new pasture.”

They’re usually grazed alongside cattle — which means they get to eat maggots from the manure and lots of other interesting things.

“OK, maybe that doesn’t sound like a great selling point,” he says, laughing.

Anyway, they cost around $6 or $7 a dozen, but they’re better and, used sparingly and appreciatively, wind up being worth it, he says. But that very idea bothers a lot of people.

“An egg is supposed to be inexpensive,” he says. “We seem to resent food when it’s expensive.”

People who wouldn’t hesitate to spend a little more for a sweater or a car will object to spending more on healthier, more sensibly grown, better-tasting food that they’re going to be putting inside their bodies, he says.

He concedes that some people can’t afford to spend an extra $100 a week on organic ingredients grown on small farms and sold through farmers’ markets, but he believes most people can make some changes that will work in their favor.

“Maybe 25 percent of the people in this country can’t move toward a diet that’s more local and organic,” he says. “The other people are making a judgment about priorities.”

Pollan does not, however, offer meal plans or recipes.

“I’m willing to take an oath,” he says, laughing again, that there will never be a Michael Pollan Cookbook or a Michael Pollan Diet. The whole idea, he says, was to produce a series of rules that people could combine with their own inclinations, to produce an infinite number of eating styles and meal plans.

“I just wanted to give people to tools to think through their own food choices,” he says.

Just then he gets a phone call. Someone has hit his car while it sat in the driveway. And it’s totaled. He has to run off and deal with that.

So maybe the next book will be about how to live without an automobile.

There’s always been a streak of the willfully impractical in Pollan’s worldview. Like the other great, radical writers whose subject is the death grip of the food industry–Joan Gussow, Marion Nestle, Eric Schlosser–he’s eloquent and persuasive; but come the revolution, he probably doesn’t belong on the tactics-and-logistics committee. What he likes best is spinning long, mesmerizing tales from his immense research, as he did in The Omnivore’s Dilemma, the book that made him a star. It’s a beautifully handled polemic against modern agribusiness until you get to the last chapter, the one that’s supposed to bring it all home.

Pollan’s way of doing this is to stage a kind of faith-based dinner party he calls “The Perfect Meal”–perfect because everything on the table will be made from ingredients grown, shot, or gathered near his home in the San Francisco Bay area, from the wild-boar pâté to the cherry galette. By the time he heads out to collect local yeast spores for the bread dough, you feel as though you’re not even reading a book anymore but instead gazing stupefied at some sort of life-sized diorama in the Museum of Natural History (“Northern California, ca. A.D. 2000–Worshipping Plants and Animals”).

The new book tries once again to bring it all home, and this time the results are more plausible. Pollan says he wrote In Defense of Food because readers who had just finished The Omnivore’s Dilemma kept asking him, “OK, now what should I eat?” His answer rounds up many themes familiar from Omnivore but tucks them into a brisk little handbook on making right-minded food choices. He’s still got a tin ear for the how-tos, but the whys are stirring enough to compensate. And Pollan, whose usual writing style is relaxed and discursive, turns out to have an unexpected gift for teaching the CliffsNotes version of his research. His master stroke is a ringing declaration of nutritional independence: “Eat food. Not too much. Mostly plants.”

It sounds like a grass-roots rebellion–literally–and that’s pretty much what he has in mind. But to his critics on the left, the very notion of starting a food revolution by changing what you personally eat is wrong-headed, and Pollan is Exhibit A. Last summer the journal Gastronomica published a special issue on food politics in which Pollan’s work was energetically trashed by scholars who can’t abide what they call his emphasis on “individual dietary purity.” In their view he’s got a bully pulpit and should be using it to rally a mass movement against Big Food, instead of encouraging people to believe that having an organic soyburger for lunch puts them in the front ranks of political activism. “No suggestion is made that we ought to alter the structural features of the food system, so that all might come to eat better,” wrote Julie Guthman of the University of California at Santa Cruz. “Rather than making political choices, we pretend … that our dietary choices will solve our personal and national problems,” said E. Melanie Du Puis, also from Santa Cruz. Aaron Bobrow-Strain of Whitman College called Pollan “more and more a lifestyle guru than a muckraking campaigner.”

I really think it’s nonsense. He may not go about organizing food co-ops or marching against Monsanto, but Pollan constantly exhorts readers to bypass supermarkets and seek out the farmer. He encourages people to lobby for changes in the grossly destructive farm bill, and his relentless reporting on agribusiness is one of the most powerful weapons that exists in the whole arsenal of food politics. It’s true that the new book trots out some trite advice (eat slowly, don’t snack, a glass of wine is good for you). But there’s no mistaking this for a wellness primer. Drawing on his own previous work and that of other researchers, he builds a case against the nutrition establishment that’s intensely political, because it’s about changing the way we think.

The science of nutrition, he argues, has little to do with food and has no business influencing our eating habits. Scientists don’t yet understand precisely what makes healthful foods healthful; they haven’t identified the full range of nutrients, and they have no idea whether packaged products “enriched” with factory-made vitamins and minerals are adequate substitutes for whole, natural foods. We even lack reliable data on exactly what Americans eat. In a delightful bit of participant journalism, Pollan tried his hand at filling out one of the dietary intake questionnaires that thousands of people contribute each year to major research projects. He couldn’t do it. Nobody could, without making up most of the answers. How many half-cup servings of yams, okra, or broccoli did he eat in the last three months? Were they fried? In stick margarine? Tub margarine? Butter, lard, nonstick spray? And these are the studies regarded as the gold standard of nutrition research, the ones that regularly burst in the news with such headlines as “Low-Fat Diet Does Not Cut Health Risks.”

Pollan’s point is that we don’t need the science in order to know what to eat. (He’d be more convincing on this issue if he hadn’t fallen head over heels for omega-3 fatty acids, a nutrient he treats as lovingly as if it were a blonde half his age.) The experts he urges us to trust are the healthy people all over the world who still favor largely traditional diets and don’t consume half their calories in sweeteners and other refined carbohydrates the way we do. Of course, they’re learning our habits fast, thanks to the corporations eager to put a chicken nugget in every pot. When Pollan says, “Eat food,” he means bring it back under your control. Accept no substitutes. Don’t let the multinationals do the cooking.

His politics are fine. What’s keeping him from being a genuine populist are his cultural antennae, which have a tendency to collapse without his noticing. Pollan is a believer, there’s a pew with his name on it at Chez Panisse; and though he writes for the rest of us, he can’t quite bring himself to take us seriously unless we can prove we’ve been born again. Early in his new book, he recalls the kind of food his mother served when he was growing up: beef stroganoff, oven-fried chicken, spaghetti, Chinese takeout. “Nowadays I don’t eat any of that stuff,” he says with relief, “and neither does my mother.” But millions of us do (well, maybe not the stroganoff), and truth to tell, there’s nothing wrong with any of those dishes if they’re occasional rather than constant. Pollan won’t have it. Home cooking derived from any era before Berkeley in the 1970s brings out the Cotton Mather in him. If you’re “the kind of cook who starts with a can of Campbell’s cream of mushroom soup,” he warns, “all bets are off.”

That’s a whole lot of sinners he’s dismissing, and I speak as someone who still lines a quiche pan with a Ritz cracker crust once in a while. Pollan knows better than anyone that a meal is far more than the sum of its parts. A dinner of tuna casserole nowadays isn’t just about the chemicals in the canned soup. It’s also about somebody’s mother, and somebody’s dog-eared copy of a Betty Crocker cookbook, and somebody’s personal best in the kitchen. Pollan himself ate a canned-soup casserole not too long ago; has he forgotten? It happened at dinner on the idyllic, radically progressive organic farm run by the Salatin family, which he describes in The Omnivore’s Dilemma. “Everything we ate had been grown on the farm, with the exception of the cream of mushroom soup that tied together Teresa’s tasty casserole,” he writes. I wish I’d been there to see if the devil made him ask for seconds.

That optimism fueled two of his earlier books: “The Botany of Desire,” about our relationship with food, and “The Omnivore’s Dilemma,” which urged variety in our diet. It’s most evident in the last of the trilogy, “In Defense of Food,” whose simple message is “Eat food. Not too much. Mostly plants.” The good news is, he thinks we can do it. Twenty years ago, it might have been difficult, but today organic, regionally grown food is more available than it has been since the food industry began controlling our consumption.

Pollan subtitles his new book “An Eater’s Manifesto,” but he’s way too polite to tell us what to eat. Instead, he uses his familiar brand of carefully researched, common-sense journalism to persuade, providing guidelines and convincing arguments. “[W]hat other animal needs professional help in deciding what it should eat?” he asks. Once, we had culture (“just a fancy word for your mother”), but culture has been replaced by “scientists and food marketers (often an unhealthy alliance of the two).” Americans are “increasingly sick and fat. Four of the top ten causes of death today are chronic diseases with well-established links to diet: coronary heart disease, diabetes, stroke, and cancer.”

We have been buffeted so often by conflicting studies that we’ve stopped thinking of food as food. We think of it as nutrition. (Recess at my children’s schools in Santa Monica is no longer called recess, but “nutrition.”) Pollan argues that food needs defending from “nutrition science on one side and from the food industry on the other — and from the needless complications around eating that together they have fostered.”

“In Defense of Food” is in three parts. The first explains the perils of “nutritionism,” like most isms a reductionist, contextless ideology. Nutritionism divides our food into nutrients (Pollan shows the complexity involved by listing the astonishing number of antioxidants in thyme) and pits them against each other: fats versus carbs, carbs versus proteins. Moreover, it “has trouble discerning qualitative distinctions among foods,” allowing marketers to avoid thorny issues of how food is grown and how humans process it. Nutritionism is a boon to food marketers, not only because it helps with splashy packaging but also because it lets them advise buyers to eat more of a particular food, exacerbating an already imbalanced, unvaried diet.

There’s an all-too convenient relationship between the scientists and the marketers, he writes: “The food industry needs theories so it can better redesign specific processed foods; a new theory means a new line of products, allowing the industry to go on tweaking the Western diet instead of making any more radical change to its business model.” The medical community also benefits; Pollan notes that as Americans spend less on food, they spend more on healthcare.

The second part, titled “The Western Diet and the Diseases of Civilization,” begins with a 1982 study, in which a group of Aborigines who had left the bush, taken up a Western diet and developed Type-2 diabetes were returned to the bush and their native diet. The diabetic abnormalities all but disappeared. Pollan uses this and other studies to show how we can regain our own lost health. “What would happen,” he asks, “if we were to start thinking about food as less of a thing and more of a relationship?” If we consume foods grown in degraded soils, or beef from cattle that have eaten grasses grown in such soils, or milk and cheese from those cattle, we won’t get the nutrients we need. This is why processed food so often has to be fortified (something marketers trumpet as a bonus).

The third section offers rules (rather, gentle suggestions) for how to “escape the Western diet.” Many are familiar, if you’ve spent any time paying attention to what you eat — for example, don’t eat packaged foods with lots of chemical ingredients. Some involve behavioral changes: Eat mostly plants, avoid supermarkets whenever possible, buy a freezer, “don’t eat anything your great-grandmother wouldn’t recognize as food,” pay more to eat less and don’t buy food where you buy gas. Some are more about how we eat than what we eat — for example, do all your eating at a table, don’t eat alone, eat slowly.

Here’s the manifesto part. Pollan isn’t just asking us to consider changing the way we eat. He’s asking us to join a movement that’s “renovating our food system in the name of health . . . in the very broadest sense of that word.” By “health,” he means avoiding diseases that kill us, but he also means happiness, pleasure, community — factors ignored in studies or marketing plans or by government agencies such as the Senate Select Committee on Nutrition and Human Needs, chaired by George McGovern in the late 1970s, so vulnerable to free-market bullying. Government and business together can stand between human beings and their instincts. That pernicious link has been weakened, Pollan believes; it has certainly become a weak link in the food chain. We know what to eat. We just have to remember it.

Dr. Melik: This morning for breakfast he requested something called “wheat germ, organic honey and tiger’s milk.”

Dr. Aragon: (chuckling) Oh, yes. Those are the charmed substances that some years ago were thought to contain life-preserving properties.

Dr. Melik: You mean there was no deep fat? No steak or cream pies or … hot fudge?

Dr. Aragon: Those were thought to be unhealthy … precisely the opposite of what we now know to be true.

Dr. Melik: Incredible.

All too credible, to Michael Pollan’s way of thinking. “Today in America,” he writes in “In Defense of Food,” “the culture of food is changing more than once a generation, which is historically unprecedented – and dizzying.” We are the victims of what Pollan sees as the media-industrial-political complex: “journalism by uncritically reporting the latest dietary studies on its front pages; the food industry by marketing dubious foodlike products on the basis of tenuous health claims; and the government by taking it upon itself to issue official dietary advice based on sketchy science in the first place and corrupted by political pressure in the second.”

Most of all, Pollan writes, we are victims of the ideology called “nutritionism,” which is based on several “unexamined assumptions,” among them that “foods are essentially the sum of their nutrient parts” and “that the whole point of eating is to maintain and promote bodily health.” Moreover, nutritionism has foisted on us a view of a kind of eternal food fight going on in our bodies: “protein against carbs; carbs against proteins; (…) fats against carbs” as well as “smaller civil wars (…) within the sprawling empires of the big three: refined carbohydrates versus fiber; animal protein versus plant protein; saturated fats versus polyunsaturated fats; (…) omega-3 fatty acids versus omega-6s.” No wonder the pharmaceutical industry makes so much money from drugs to combat heartburn.

And now we seem to be entering the “Sleeper” future, in which deep fat may make a comeback. “What the Soviet Union was to the ideology of Marxism,” Pollan observes, “the Low-Fat Campaign is to the ideology of nutritionism: its supreme test and, as now is coming clear, its most abject failure.” More and more scientists are questioning whether there really is a connection between dietary fat and heart disease. Not only that, Pollan quotes an article from the Journal of the American College of Nutrition: “It is now increasingly recognized that the low-fat campaign has been based on little scientific evidence and may have caused unintended health consequences.” In other words, the low-fat, low-cholesterol campaign not only hasn’t helped stem such problems as obesity, heart disease and diabetes, but it may have in fact made them worse.

Readers of his engagingly written earlier books on food, “The Botany of Desire” and “The Omnivore’s Dilemma,” know that Pollan is not just another Berkeley food crank. Moreover, his is not the only new book proclaiming the hazards of nutritionism. Pollan himself cites science writer Gary Taubes’ recently published “Good Calories, Bad Calories” as an “important” book “blowing the whistle on the science behind the low-fat campaign.” Taubes’ book is a heavier read than Pollan’s, thickly documented and heavy on the science. Pollan faults it for not being skeptical enough about the current identification of carbohydrates as the enemy that fats were once thought to be: “As its title suggests, ‘Good Calories, Bad Calories,’ valuable as it is, does not escape the confines of nutritionism.”

Pollan urges us to relax and not worry so much about food. At the beginning of the book he provides a mantra: “Eat food. Not too much. Mostly plants.” After spending much of the book explaining why almost all nutritional advice in the past 30 or 40 years has been misleading, unsubstantiated, bogus and even counterproductive, he unpacks his mantra for us concisely and amusingly. “Don’t eat anything your great-grandmother wouldn’t recognize as food,” he advises. This needs a bit more explanation. After all, many of our great-grandmothers weren’t exposed to the great multicultural bounty we find in stores and restaurants, so a lot of them wouldn’t recognize some perfectly wholesome stuff as edible. Calamari, for example, or tofu. One imagines Great-Grandma’s reaction to such now-commonplace fare as artichokes (“You want me to cook a thistle?”) or yogurt (“That milk is sour!”). To paraphrase Jonathan Swift, it was a brave great-grandmother who ate the first oyster.

But Pollan’s point is this: Great-Grandmother never cooked with guar gum, carrageenan, mono- and diglycerides, hydrolyzed vegetable protein, modified food starch, soy lecithin and any number of other ingredients found in processed food. She would never eat cotton, but cottonseed oil is commonplace in all sorts of the “edible foodlike substances” found in supermarkets today.

Pollan’s advice is sensible and even inspiring. It can, however, be faulted as a little elitist. It’s not that hard if, like Pollan, you live in Berkeley, where Alice Waters is guide and guru, to shop carefully at farmers’ markets and specialty stores, to spend more to get better stuff, to cook your meals, and to eat them slowly and at a table with good company. But God help you if you’re a single parent working long hours and living in a poorer neighborhood where there aren’t even any supermarkets. A bag of Whoppers or a bucket of KFC is probably your inevitable choice.

And, in the end, this thoughtful, entertaining and helpful book does wind up being a little more alarmist than Pollan pretends it is. The very thought that a book needs to be written “In Defense of Food” is unsettling. It might instead have been called “Fear of Feeding.”