The Omnivore's Dilemma: A Natural History of Four Meals

by Michael Pollan

The chemical fertilizer industry (along with that of pesticides, which are based on poison gases developed for the war) is the product of the government’s effort to convert its war machine to peacetime purposes.

Chemists call this process of taking atoms from the atmosphere and combining them into molecules useful to living things “fixing” that element. Until a German Jewish chemist named Fritz Haber figured out how to turn this trick in 1909, all the usable nitrogen on earth had at one time been fixed by soil bacteria living on the roots of leguminous plants

Haber’s story embodies the paradoxes of science: the double edge to our manipulations of nature, the good and evil that can flow not only from the same man but the same knowledge.

What had been a local, sun-driven cycle of fertility, in which the legumes fed the corn which fed the livestock which in turn (with their manure) fed the corn, was now broken.

Since the farm no longer needs to generate and conserve its own fertility by maintaining a diversity of species, synthetic fertilizer opens the way to monoculture, allowing the farmer to bring the factory’s economies of scale and mechanical efficiency to nature.

harvest, dry, and transport the corn, you find that every bushel of industrial corn requires the equivalent of between a quarter and a third of a gallon of oil to grow it—or around fifty gallons of oil per acre of corn. (Some estimates are much higher.) Put another way, it takes more than a calorie of fossil fuel energy to produce a calorie of food;

But what happens to the one hundred pounds of synthetic nitrogen that Naylor’s corn plants don’t take up? Some of it evaporates into the air, where it acidifies the rain and contributes to global warming.

America’s farmers had long been making political trouble for Wall Street and Washington; in the words of historian Walter Karp, “since the Civil War at least, the most unruly, the most independent, the most republican of American citizens have been the small farmers.” Beginning with the populist revolt of the 1890s, farmers had made common cause with the labor movement, working together to check the power of corporations.

“The free market has never worked in agriculture and it never will. The economics of a family farm are very different than a firm’s: When prices fall, the firm can lay off people, idle factories, and make fewer widgets. Eventually the market finds a new balance between supply and demand. But the demand for food isn’t elastic; people don’t eat more just because food is cheap. And laying off farmers doesn’t help to reduce supply. You can fire me, but you can’t fire my land, because some other farmer who needs more cash flow or thinks he’s more efficient than I am will come in and farm it. Even if I go out of business this land will keep producing corn.”

what the Treasury is really subsidizing are the buyers of all that cheap corn.

while number 2 field corn certainly looks like the corn you would eat, and is directly descended from the maize Friar Sahagún’s Aztecs worshipped as the source of life, it is less a food than an industrial raw material—and an abstraction. The kernels are hard to eat, but if you soak them in water for several hours you’ll find they taste less like corn than lightly corn-flavored starch.

Another way to look at this 10-billion-bushel pile of commodity corn—a naturalist’s way of looking at it *—is that industrial agriculture has introduced a vast new stock of biomass to the environment, creating what amounts to an imbalance—a kind of vacuum in reverse. Ecology teaches that whenever an excess of organic matter arises anywhere in nature, creatures large and small inevitably step forward to consume it, sometimes creating whole new food chains in the process. In this case the creatures feasting on the surplus biomass are both metaphorical and real: There are the agribusiness corporations, foreign markets, and whole new industries (such as ethanol), and then there are the food scientists, livestock, and human eaters, as well as the usual array of microorganisms (such as E.coli O157:H7).

Such is the protean, paradoxical nature of the corn in that pile that getting rid of it could contribute to obesity and to hunger both.

I’d traveled to Poky early one January with the slightly improbable notion of visiting one particular resident, though as I nosed my rental car through the feedlot’s rolling black sea of bovinity, I began to wonder if this was realistic.

Already in their short history CAFOs have produced more than their share of environmental and health problems: polluted water and air, toxic wastes, novel and deadly pathogens.

Raising animals on old-fashioned mixed farms such as the Naylors’ used to make simple biological sense: You can feed them the waste products of your crops, and you can feed their waste products to your crops. In fact, when animals live on farms the very idea of waste ceases to exist; what you have instead is a closed ecological loop—what in retrospect you might call a solution.

They can do this because they possess what is surely the most highly evolved digestive organ in nature: the rumen. About the size of a medicine ball, the organ is essentially a twenty-gallon fermentation tank in which a resident population of bacteria dines on grass. Living their unseen lives at the far end of the food chain that culminates in a hamburger, these bacteria have, like the grasses, coevolved with the cow, whom they feed.

This industrial logic is rational and even irresistible—after all, it has succeeded in making beef everyday fare for millions of people for whom it once represented a luxury. And yet the further you follow it, the more likely you are to begin wondering if that rational logic might not also be completely mad.

Yet, having started out from George Naylor’s farm, I understood that the corn on which this place runs is implicated in a whole other set of ecological relationships powered by a very different source of energy—the fossil fuel it takes to grow all that corn. So if the modern CAFO is a city built upon commodity corn, it is a city afloat on an invisible sea of petroleum.

Yet this corn-fed meat is demonstrably less healthy for us, since it contains more saturated fat and less omega-3 fatty acids than the meat of animals fed grass. A growing body of research suggests that many of the health problems associated with eating beef are really problems with corn-fed beef. (Modern-day hunter-gatherers who subsist on wild meat don’t have our rates of heart disease.) In the same way ruminants are ill adapted to eating corn, humans in turn may be poorly adapted to eating ruminants that eat corn.

Calories are calories, and corn is the cheapest, most convenient source of calories on the market. Of course, it was the same industrial logic—protein is protein—that made feeding rendered cow parts back to cows seem like a sensible thing to do, until scientists figured out that this practice was spreading bovine spongiform encephalopathy (BSE), more commonly known as mad cow disease.

Some evolutionary biologists believe that evolution selected against cannibalism as a way to avoid such infections; animals’ aversion to their own feces, and the carcasses of their species, may represent a similar strategy.

One of the most troubling things about factory farms is how cavalierly they flout these evolutionary rules, forcing animals to overcome deeply ingrained aversions.

Some public health experts worry that since the bovine meat and bonemeal that cows used to eat is now being fed to chickens, pigs, and fish, infectious prions could find their way back into cattle when they’re fed the protein of the animals that have been eating them.

Most of the antibiotics sold in America today end up in animal feed, a practice that, it is now generally acknowledged (except in agriculture), is leading directly to the evolution of new antibiotic-resistant superbugs.

Most of the microbes that reside in the gut of a cow and find their way into our food get killed off by the strong acids in our stomachs, since they evolved to live in the neutral pH environment of the rumen. But the rumen of a corn-fed feedlot steer is nearly as acidic as our own stomachs, and in this new, man-made environment new acid-resistant strains of E. coli,

of which O157:H7 is one, have evolved—yet another creature recruited by nature to absorb the excess biomass coming off the Farm Belt. The problem with these bugs is that they can shake off the acid bath in our stomachs—and then go on to kill us. By acidifying the rumen with corn we’ve broken down one of our food chain’s most important barriers to infection. Yet another solution turned into a problem.

Jim Russell, a USDA microbiologist on the faculty at Cornell, has found that switching a cow’s diet from corn to grass or hay for a few days prior to slaughter reduces the population of E.coli O157:H7 in the animal’s gut by as much as 80 percent. But such a solution (Grass?!) is considered wildly impractical by the cattle industry and (therefore) by the USDA. Their preferred solution for dealing with bacterial contamination is irradiation—essentially, to try to sterilize the manure getting into the meat.

What?!

I don’t have a sufficiently vivid imagination to look at my steer and see a barrel of oil, but petroleum is one of the most important ingredients in the production of modern meat, and the Persian Gulf is surely a link in the food chain that passes through this (or any) feedlot. Steer 534 started his life part of a food chain that derived all of its energy from the sun, which nourished the grasses that nourished him and his mother. When 534 moved from ranch to feedlot, from grass to corn, he joined an industrial food chain powered by fossil fuel—and therefore defended by the U.S. military, another never-counted cost of cheap food.

what we are, or have become, is not just meat but number 2 corn and oil.

At each step more fresh water is added—it takes about five gallons to process a bushel of corn, and prodigious amounts of energy. Wet milling is an energy-intensive way to make food; for every calorie of processed food it produces, another ten calories of fossil fuel energy are burned.

Step back for a moment and behold this great, intricately piped stainless steel beast: This is the supremely adapted creature that has evolved to help eat the vast surplus biomass coming off America’s farms, efficiently digesting the millions of bushels of corn fed to it each day by the trainload. Go around back of this beast and you’ll see a hundred different spigots, large and small, filling tanker cars of other trains with HFCS, ethanol, syrups, starches, and food additives of every description.

This leaves companies like General Mills and McDonald’s with two options if they hope to grow faster than the population: figure out how to get people to spend more money for the same three-quarters of a ton of food, or entice them to actually eat more than that. The two strategies are not mutually exclusive, of course, and the food industry energetically pursues them both at the same time. Which is good news indeed for the hero of our story, for it happens that turning cheap corn into complex food systems is an excellent way to achieve both goals.

The omnivore’s predilection to eat a variety of species is tricked by this protean plant, and even the biological limit on his appetite is overcome.

The Alcoholic Republic has long since given way to the Republic of Fat; we’re eating today much the way we drank then, and for some of the same reasons. According to the surgeon general, obesity today is officially an epidemic; it is arguably the most pressing public health problem we face, costing the health care system an estimated $90 billion a year.

You hear plenty of explanations for humanity’s expanding waistline, all of them plausible. Changes in lifestyle (we’re more sedentary; we eat out more). Affluence (more people can afford a high-fat Western diet). Poverty (healthier whole foods cost more). Technology (fewer of us use our bodies in our work; at home, the remote control keeps us pinned to the couch). Clever marketing (supersized portions; advertising to children). Changes in diet (more fats; more carbohydrates; more processed foods).

This is what makes high-fructose corn syrup such a clever thing to do with a bushel of corn: By inducing people to consume more calories than they otherwise might, it gets them to really chomp through the corn surplus. Corn sweetener is to the republic of fat what corn whiskey was to the alcoholic republic.

Human appetite, it turns out, is surprisingly elastic, which makes excellent evolutionary sense: It behooved our hunter-gatherer ancestors to feast whenever the opportunity presented itself, allowing them to build up reserves of fat against future famine. Obesity researchers call this trait the “thrifty gene.”

You begin to see why processing foods is such a good strategy for getting people to eat more of them. The power of food science lies in its ability to break foods down into their nutrient parts and then reassemble them in specific ways that, in effect, push our evolutionary buttons, fooling the omnivore’s inherited food selection system.

Food systems can cheat by exaggerating their energy density, tricking a sensory apparatus that evolved to deal with markedly less dense whole foods.

recent study in the American Journal of Clinical Nutrition compared the “energy cost” of different foods in the supermarket. The researchers found that a dollar could buy 1,200 calories of potato chips and cookies; spent on a whole food like carrots, the same dollar buys only 250 calories. On the beverage aisle, you can buy 875 calories of soda for a dollar, or 170 calories of fruit juice from concentrate.

Very simply, we subsidize high-fructose corn syrup in this country, but not carrots. While the surgeon general is raising alarms over the epidemic of obesity, the president is signing farm bills designed to keep the river of cheap corn flowing, guaranteeing that the cheapest calories in the supermarket will continue to be the unhealthiest.

I said before that McDonald’s serves a kind of comfort food, but after a few bites I’m more inclined to think they’re selling something more schematic than that—something more like a signifier of comfort food. So you eat more and eat more quickly, hoping somehow to catch up to the original idea of a cheeseburger or French fry as it retreats over the horizon. And so it goes, bite after bite, until you feel not satisfied exactly, but simply, regrettably, full.

he’ll tell you in no uncertain terms, “I’m a grass farmer.” The first time I heard this designation I didn’t get it at all—hay seemed the least (and least edible) of his many crops, and he brought none of it to market. But undergirding the “farm of many faces,” as he calls it, is a single plant—or rather that whole community of plants for which the word “grass” is shorthand.

Salatin’s audacious bet is that feeding ourselves from nature need not be a zero-sum proposition, one in which if there is more for us at the end of the season then there must be less for nature—less topsoil, less fertility, less life. He’s betting, in other words, on a very different proposition, one that looks an awful lot like the proverbially unattainable free lunch.

Because a healthy soil digests the dead to nourish the living, Salatin calls it the earth’s stomach.

“All flesh is grass.” The Old Testament’s earthy equation reflects a pastoral culture’s appreciation of the food chain that sustained it, though the hunter-gatherers living on the African savanna thousands of years earlier would have understood the flesh-grass connection just as well.

Our inclination toward grass, which has the force of a tropism, is frequently cited as a prime example of “biophilia,” E. O. Wilson’s coinage for what he claims is our inherited genetic attraction for the plants and animals and landscapes with which we coevolved.

Our species’ coevolutionary alliance with the grasses has deep roots and has probably done more to ensure our success as a species than any other, with the possible exception of our alliance with the trillion or so bacteria that inhabit the human gut. Working together, grass and man have overspread much of the earth, far more of it than would ever have been possible working alone.

Take the “range-fed” sirloin steak I recently eyed in the meat case. According to the brochure on the counter, it was formerly part of a steer that spent its days “living in beautiful places” ranging from “plant-diverse, high-mountain meadows to thick aspen groves and miles of sagebrush-filled flats.” Now a steak like that has got to taste better than one from Safeway, where the only accompanying information comes in the form of a number: the price, I mean, which you can bet will be considerably less. But I’m evidently not the only shopper willing to pay more for a good story.