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In Defense of Food by Michael Pollan

In Defense of Food

RATING: 9/10…READ: October 5, 2011

Shocking. Jaw Dropping. Disturbing. In Defense of Food chronicles what has happened to our Food System and what we can do about it. If you care at all about your health, you must must must read this book.

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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.

If you’re concerned about your health, you should probably avoid products that make health claims. Why? Be­ cause a health claim on a food product is a strong indication it’s not really food, and food is what you want to eat.

What is driving such relentless change in the American diet? One force is a thirty-two-billion-dollar food-marketing machine that thrives on change for its own sake. Another is the constantly shifting ground of nutrition science that, depending on your point of view, is steadily advancing the frontiers of our knowledge about diet and health or is just changing its mind a lot because it is a flawed science that knows much less than it cares to admit.

a Harvard study brought the hopeful piece of news that simply by eating a couple of servings of fish each week (or by downing enough fish oil tablets) you could cut your risk of dying from a heart attack by more than a third.

But if food and eating stand in need of a defense, from whom, or what, do they need 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.

W e forget that, historically, people have eaten for a great many reasons other than biological necessity. Food is also about pleasure, about com­ munity, about family and spirituality, about our relationship to the natural world, and about expressing our identity. As long as humans have been taking meals together, eating has been as much about culture as it has been about biology.

We are becoming a nation of orthorexics: people with an unhealthy obsession with healthy eating.

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.

3 Principle constituents of food—protein, fat, carbohydrates aka macronutrients.

“vitamines” in 1912 (“vita-” for life and “-amines” for organic compounds organized around nitrogen).

Say what you will about this or that food, you are not allowed officially to tell people to eat less of it or the industry in question will have you for lunch.

When a few years later the National Academy of Sciences looked into the question of diet and cancer, it was careful to frame its recommendations nutrient by nutrient rather than food by food, to avoid offending any powerful interests.

The first thing to understand about nutritionism is that it is not the same thing as nutrition. As the “-ism” suggests, it is not a scientific subject but an ideology.

Since nutrients, as compared with foods, are invisible and therefore slightly mysterious, it falls to the scientists (and to the journalists through whom the scientists reach the public) to explain the hidden reality of foods to us. In form this is a quasireligious idea, suggesting the visible world is not the one that really matters, which implies the need for a priesthood. For to enter a world where your dietary salvation depends on unseen nutrients, you need plenty of expert help.

Ever since, the history of modern nutritionism has been a history of macronutrients at war: protein against carbs; carbs against proteins, and then fats; fats against carbs. Beginning with Liebig, in each age nutritionism has organized most of its energies around an imperial nutrient: protein in the nineteenth century, fat in the twentieth, and, it stands to reason, carbohydrates will occupy our attention in the twenty-first.

The entire history of baby formula has been the history of one overlooked nutrient after another: Liebig missed the vitamins and amino acids, and his successors missed the omega-3s, and still to this day babies fed on the most “nutritionally complete” formula fail to do as well as babies fed human milk.

1893—dying imitation butter pink / overturned in 1898

1938—FDA requires the word imitation on imitation food products

1973—overturned by the FDA (Logic: the imitation food has the same nutrients as the real food, therefore it must be the same)

As long as the new fake foods were engineered to be nutritionally equivalent to the real article, they could no longer be considered fake.

Nutritionism had become the official ideology of the Food and Drug Administration; for all practical purposes the government had redefined foods as nothing more than the sum of their recognized nutrients.

Scientists can find an antioxidant in just about any plant- based food they choose to study.

The amount of saturated fat in the diet probably may have little if any bearing on the risk of heart disease, and evidence that increasing polyunsaturated fats in the diet will reduce risk is slim to nil.

“there is little direct evidence linking higher egg consumption and increased risk of CHD”—surprising, because eggs are particularly high in cholesterol. (Types of Dietary Fat and Risk of Coronary Heart Disease: A Critical Review: Harvard School of Public Health.

It turns out that “a higher in­ take of trans fat can contribute to increased risk of CHD through multiple mechanisms”; to wit, it raises bad cholesterol and lowers good cholesterol (something not even the evil saturated fats can do); it increases triglycerides, a risk factor for CHD; it promotes inflammation and possibly thrombogenesis (clotting) , and it may promote insulin resistance.

Many date the current epidemic of obesity and diabetes to the late 1970s, when Americans began bingeing on carbohydrates, ostensibly as a way to avoid the evils of fat.

Every course correction in nutritionist advice gives reason to write new diet books and articles, manufacture a new line of products, and eat a whole bunch of even more healthy new food products. And if a product is healthy by design and official sanction, then eating Jots of it must be healthy too—maybe even more so.

Not only does nutritionism favor ever more novel kinds of highly processed foods (which are by far the most profitable kind to make), it actually enlists the medical establishment and the government in the promotion of those products. Play your cards right and you can even get the American Heart Association to endorse your new breakfast cereal as “heart healthy.”

But why do we even need a nutritional philosophy in the first place? Perhaps because we Americans have always had a problem taking pleasure in eating. W e certainly have gone to unusual lengths to avoid it. Harvey Levenstein, who has written two illuminating histories of American food culture, suggests that the sheer abundance of food in America has bred “a vague indifference to food, manifested in a tendency to eat and run, rather than to dine and savor.”

Here’s how Harvey Levenstein sums up the quasiscientific beliefs that have shaped American attitudes toward food for more than a century: “that taste is not a true guide to what should be eaten; that one should not simply eat what one enjoys; that the important components of foods cannot be seen or tasted, but are discernible only in scientific laboratories; and that experimental science has produced rules of nutrition which will prevent illness and encourage longevity.” Levenstein could be describing the main tenets of nutritionism.

The theory is that refined carbohydrates interfere with insulin metabolism in ways that increase hunger and promote overeating and fat storage in the body.

A ten-year study of heart disease mortality published in the New England Journal of Medicine in 1998 strongly suggests that most of the decline in deaths from heart disease is due not to changes in lifestyle, such as diet, but to improvements in medical care.

The problem starts with the nutrient. Most nutritional science involves studying one nutrient at a time, a seemingly un­ avoidable approach that even nutritionists who do it will tell you is deeply flawed. “The problem with nutrient-by-nutrient nutrition science,” points out 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.”

If nutrition scientists know this, why do they do it any­ way? Because a nutrient bias is built into the way science is done. Scientists study variables they can isolate; if they can’t isolate a variable, they won’t be able to tell whether its presence or absence is meaningful.

Curiously, the human digestive tract has roughly as many neurons as the spinal column. We don’t yet know exactly what they’re up to, but their existence suggests that much more is going on in digestion than simply the breakdown of foods into chemicals.

As soon as you remove these crucial molecules from the context of the whole foods they’re found in, as we’ve done in creating anti­ oxidant supplements, they don’t seem to work at all. Indeed, in the case of beta-carotene ingested as a supplement, one study has suggested that in some people it may actually increase the risk of certain cancers. Big oops.

We eat foods in combinations and in orders that can affect how they’re metabolized. The carbohydrates in a bagel will be absorbed more slowly if the bagel is spread with peanut butter; the fiber, fat, and protein in the peanut butter cushion the insulin response, thereby blunting the impact of the carbohydrates. (This is why eating dessert at the end of the meal rather than the beginning is probably a good idea.)

Much of what we know about the health benefits of a vegetarian diet is based on studies of Seventh-Day Adventists, who muddy the nutritional picture by abstaining from alcohol and tobacco as well as meat. These extraneous but unavoidable factors are called, aptly, confounders.

People who take supplements are healthier than the population at large, yet their health probably has nothing whatsoever to do with the supplements they take— most of which recent studies have suggested are worthless. Supplement takers tend to be better educated, more affluent people who, almost by definition, take a greater than usual interest in personal health—confounders that probably account for their superior health.

It’s worth keeping in mind that a far more powerful predictor of heart disease than either diet or exercise is social class.

“Validation studies” of dietary trials like the Women’s Health Initiative or the Nurses’ Study, which rely on “food-frequency questionnaires” filled out by subjects several times a year, indicate that people on average eat between a fifth and a third more than they say they do on questionnaires.

Block thinks the problem with nutrition science, which she feels “has led us astray,” is not the FFQ itself but mis-and over interpretation of the data derived from the FFQ, a tool for which she makes realistic but strikingly modest claims: “The real purpose of the FFQ is to rank people” on their relative consumption of, say, fruits and vegetables or total calories. “If someone reports consuming five hundred calories a day, that’s not true, obviously, but you can say they’re probably at the low end of the spectrum. People over worry about accuracy.”

–This was not the sort of thing I expected to hear from an epidemiologist. But then neither was this: “I don’t believe any­ thing I read in nutritional epidemiology anymore. I’m so skeptical at this point.”

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.

When you adjust for age, rates of chronic diseases like cancer and type 2 diabetes are considerably higher today than they were in 1900. That is, the chances that a sixty-or seventy-year-old suffers from cancer or type 2 diabetes are far greater today than they were a century ago.

What would happen if we were to start thinking about food as less of a thing and more of a relationship? In nature, that is of course precisely what eating has always been: relationships among species in systems we call food chains, or food webs, that reach all the way down to the soil. Species coevolve with the other species that they eat, and very often there develops a relationship of interdependence: I’ll feed you if you spread around my genes.

Refined flour is the first fast food.

The big money has always been in processing foods, not selling them whole, and the industry’s investment in the reductionist approach to food is probably safe. The fact is, there is something in us that loves a refined carbohydrate, and that something is the human brain. The human brain craves carbohydrates reduced to their energy essence, which is to say pure glucose. Once industry figured out how to transform the seeds of grasses into the chemical equivalent of sugar, there was probably no turning back.

The energy density of these refined carbohydrates contributes to obesity in two ways. First, we consume many more calories per unit of food; the fiber that’s been removed from these foods is precisely what would have made us feel full and stop eating. Also, the flash flood of glucose causes insulin levels to spike and then, once the cells have taken all that glucose out of circulation, drop precipitously, making us think we need to eat again.

Our ancient evolutionary relationship with the seeds of grasses and fruit of plants has given way, abruptly, to a rocky marriage with glucose and fructose.

Thousands of plant and animal varieties have fallen out of commerce in the last century as industrial agriculture has focused its attentions on a small handful of high-yielding (and usually patented) varieties, with qualities that suited them to things like mechanical harvesting and processing. Half of all the broccoli grown commercially in America today is a single variety—Marathon—notable for its high yield. The overwhelming majority of the chickens raised for meat in America are the same hybrid, the Cornish cross; more than 99 percent of the turkeys are Broad-Breasted Whites.

Why corn and soy? Because these two plants are among nature’s most efficient transformers of sunlight and chemical fertilizer into carbohydrate energy (in the case of corn) and fat and protein (in the case of soy)—if you want to extract the maximum amount of macronutrients from the American farm belt, corn and soy are the crops to plant. (It helps that the government pays farmers to grow corn and soy, subsidizing every bushel they produce.)

Government figures from England tell a similar story: declines since the fifties of 10 percent or more in levels of iron, zinc, calcium, and selenium across a range of food crops. To put this in more concrete terms, you now have to eat three apples to get the same amount of iron as you would have gotten from a single 1940 apple, and you’d have to eat several more slices of bread to get your recommended daily allowance of zinc than you would have a century ago.

Halweil cites several studies demonstrating that when older crop varieties are grown side by side with modern cultivars, the older ones typically have lower yields but substantially higher nutrient levels.

Clearly the achievements of industrial agriculture have come at a cost: It can produce a great many more calories per acre, but each of those calories may supply less nutrition than it formerly did.

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, predictably, we’re eating a whole lot more, at least 300 more calories a day than we consumed in 1985.

A diet based on quantity rather than quality has ushered a new creature onto the world stage: the human being who manages to be both overfed and undernourished, two characteristics seldom found in the same body in the long natural history of our species.

Omega-3 s appear to play an important role in neurological development and processing (the highest concentrations of omega-3s in humans are found in the tissues of the brain and the eyes), visual acuity (befitting their role in photosynthesis), the permeability of cell walls, the metabolism of glucose, and the calming of inflammation. Omega-6s are involved in fat storage (which is what they do for the plant), the rigidity of cell walls, clotting, and the inflammation response.

It helps to think of omega-3s as fleet and flexible, omega-6s as sturdy and slow.

Clinical studies have found that increasing the omega-3s in one’s diet may reduce the chances of heart attack by a third.

Omega- 6s exist in a kind of zero-sum relationship with omega-3s, counteracting most of the positive effects of omega-3 through­ out the body. Merely adding omega-3s to the diet—by taking supplements, say—may not do much good unless we also reduce the high levels of omega-6s that have entered the Western diet with the advent of processed foods, seed oils, and foods from animals raised on grain.

Joseph Hibbeln, the researcher at the National Institutes of Health who conducted population studies correlating omega-3 consumption with everything from stroke to suicide, says that the billions we spend on anti-inflammatory drugs such as aspirin, ibuprofen, and acetaminophen is money spent to undo the effects of too much omega-6 in the diet.

Apparently it is easier, or at least a lot more profitable, to change a disease of civilization into a lifestyle than it is to change the way that civilization eats.

If my explorations of the food chain have taught me anything, it’s that it is a food chain, and all the links in it are in fact linked: the health of the soil to the health of the plants and animals we eat to the health of the food culture in which we eat them to the health of the eater, in body as well as mind.

–DON’T EAT ANYTHING YOUR GREAT GRAND­ MOTHER WOULDN’T RECOGNIZE AS FOOD.

–AVOID FOOD PRODUCTS CONTAINING INGRE­ DIENTS THAT ARE A) UNFAMILIAR, B) UNPRO­ NOUNCEABLE, C) MORE THAN FIVE IN NUMBER, OR THAT INCLUDE D) HIGH-FRUCTOSE CORN S Y RU P.

The American Heart Association currently bestows (for a fee) its heart-healthy seal of approval on Lucky Charms, Cocoa Puffs, and Trix cereals, Yoo-hoo lite chocolate drink, and Healthy Choice’s Premium Caramel Swirl Ice Cream Sandwich—this at a time when scientists are coming to recognize that dietary sugar probably plays a more important role in heart disease than dietary fat.

–SHOP THE PERIPHERIES OF THE SUPERMARKET AND STAY OUT OF THE MIDDLE.

–GET OUT OF THE SUPERMARKET WHENEVER POSSIBLE. (shop at farmers markets as much as possible)

As for supermarket organic produce, it too is likely to have come from far away—from the industrial organic farms of California or, increasingly, China.* And while it’s true that the organic label guarantees that no synthetic pesticides or fertilizers have been used to produce the food, many, if not most, of the small farms that supply farmers’ markets are organic in everything but name. To survive in the farmers’ market or CSA economy, a farm will need to be highly diversified, and a diversified farm usually has little need for pesticides; it’s the big monocultures that can’t survive without them.

Food safety didn’t become a national or global problem until the industrialization of the food chain attenuated the relationships between food producers and eaters.

Yes, shopping this way takes more money and effort, but as soon 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.

Eat mostly plants, especially leaves.

Unlike plants, which we can’t live without, we don’t need to eat meat—with the exception of vitamin B12, every nutrient found in meat can be obtained somewhere else.

But meat, which humans have been going to heroic lengths to obtain and have been relishing for a very long time, is nutritious food, supplying all the essential amino acids as well as many vitamins and minerals, and I haven’t found a compelling health reason to exclude it from the diet.

What exactly it is in meat we need to worry about (the saturated fat? the type of iron? the carcinogens produced in curing and cooking it?) is unclear; the problem could be simply that eating lots of it pushes plants out of the diet.

–YOU ARE WHAT WHAT YOU EAT EATS TOO. (That is, the diet of the animals we eat has a bearing on the nutritional quality, and healthfulness, of the food itself, whether it is meat or milk or eggs.)

Biodiversity in the diet means more biodiversity in the fields. To shrink the monocultures that now feed us would mean farmers won’t need to spray as much pesticide or chemical fertilizer, which would mean healthier soils, healthier plants and animals, and in turn healthier people.

–EAT WILD FOODS WHEN YOU CAN

–BE THE KIND OF PERSON WHO TAKES SUPPLEMENTS

–EAT MORE LIKE THE FRENCH. OR THE ITALIANS. OR THE JAPANESE. OR THE INDIANS. OR THE GREEKS .

The context in which a food is eaten can be nearly as important as the food itself.

–REGARD NON-TRADITIONAL FOODS WITH SKEPTICSM

Soy isoflavones, found in most soy products, are compounds that resemble estrogen, and in fact bind to human estrogen receptors. But it is unclear whether these so-called phytoestrogens actually behave like estrogen in the body or only fool it into thinking they’re estrogen. Either way the phytoestrogens might have an effect (good or bad) on the growth of certain cancers, the symptoms of menopause, and the function of the endocrine system. Because of these uncertainties, the FDA has declined to grant GRAS (“generally regarded as safe”) status to soy isoflavones used as a food additive.

–DON’T LOOK FOR THE MAGIC BULLET IN THE TRADITIONAL DIET

The whole of a dietary pattern is evidently greater than the sum of its parts.

But it seems unlikely that any single food, nutrient, or mechanism will ever explain the French paradox; more likely, we will someday come to realize there never was a paradox. Dietary paradoxes are best thought of as breakdowns in nutritionist thinking, a sign of something wrong with the scientific consensus rather than the diet in question.

A glass of wine a day is fine

Paul Rozin has confirmed many of these observations in a comparison of French and American eating habits conducted in restaurants in Paris and Philadelphia. Rozin focused on portion size and time spent eating. He found that serving sizes in France, both in restaurants and supermarkets, are considerably smaller than they are in the United States. This matters because most people have what psychologists call a unit bias—we tend to believe that however big or small the portion served, that’s the proper amount to eat. Rozin also found that the French spend considerably more time enjoying their tiny servings than we do our Brobdingnagian ones. “Although they eat less than Americans,” Rozin writes, “the French spend more time eating, and hence get more food experience while eating less.” He suggests that the French gift for extracting more food experience from fewer calories may help explain why the French are slimmer and healthier than we are. This sounds like an eminently sensible approach to eating and suggests an overarching policy that might nudge us in that direction.

In 1960 Americans spent 17.5 percent of their income on food and 5.2 percent of national income 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. I have to think that by spending a little more on healthier food we could reduce the amount we have to spend on health care.

–DO ALL YOUR EATING AT A TABLE

–DO NOT GET YOUR FUEL FROM THE SAME PLACE YOUR CAR DOES

–TRY NOT TO EAT ALONE

–CONSULT YOUR CUT (80% full rule)

–EAT SLOWLY

–COOK, AND IF YOU CAN, PLANT A GARDEN