In Defense of Food
Page 10
So what did Price learn? First, that isolated populations eating a wide variety of traditional diets had no need of dentists whatsoever. (Well, almost no need of dentists: The “sturdy mountaineers” of Switzerland, who never met a toothbrush, had teeth covered in a greenish slime-but underneath that Price found perfectly formed teeth virtually free of decay.) Wherever he found an isolated primitive race that had not yet encountered the “displacing foods of modern commerce”-by which he meant refined flour, sugar, canned and chemically preserved foods, and vegetable oils-he found little or no evidence of “modern degeneration”-by which he meant chronic disease, tooth decay, and malformed dental arches. Either there was something present in the Western diet that led to these problems or there was something absent from it.
Wherever Price went he took pictures of teeth and collected samples of food, which he sent home to Cleveland to be analyzed for macronutrient and vitamin content. He found that his native populations were eating a diet substantially higher in vitamins A and D than that of modern Americans-on average ten times as much. This owed partly to the fact that, as was already understood by the 1930s, the processing of foods typically robs them of nutrients, vitamins especially. Store food is food designed to be stored and transported over long distances, and the surest way to make food more stable and less vulnerable to pests is to remove the nutrients from it. In general, calories are much easier to transport-in the form of refined grain or sugar-than nutrients, which are liable to deteriorate or attract the attention of bacteria, insects, and rodents, all keenly interested in nutrients. (More so, apparently, than we are.) Price concluded that modern civilization had sacrificed much of the quality of its food in the interests of quantity and shelf life.
Price identified no single ideal diet-he found populations that thrived on seafood diets, dairy diets, meat diets, and diets in which fruits, vegetables, and grain predominated. The Masai of Africa consumed virtually no plant foods at all, subsisting on meat, blood, and milk. Seafaring groups in the Hebrides consumed no dairy at all, subsisting on a diet consisting largely of seafood and oats made into porridges and cakes. The Eskimos he interviewed lived on raw fish, game meat, fish roe, and blubber, seldom eating anything remotely green. Along the Nile near Ethiopia, Price encountered what he judged to be the healthiest populations of all: tribes that subsisted on milk, meat, and blood from pastured cattle as well as animal food from the Nile River. Price found groups that ate diets of wild animal flesh to be generally healthier than the agriculturists who relied on cereals and other plant foods; the agriculturists tended to have somewhat higher levels of tooth decay (though still low by our standards). Price noted that many of the peoples he visited particularly prized organ meats, in which he found high levels of fat-soluble vitamins, minerals, and “activator X,” a term of his own invention that is probably vitamin K2. Almost everywhere he went, he noted the high value people placed on seafood, which even mountain-dwelling groups would go to great lengths to procure, trading with coastal tribes for dried fish eggs and such. But the common denominator of good health, he concluded, was to eat a traditional diet consisting of fresh foods from animals and plants grown on soils that were themselves rich in nutrients.
Price paid special attention to the quality of animal-based foods and its link to what those animals ate. He compared the vitamin content of butter produced from cows grazing on spring grass to that of animals on winter forages; not only were levels of vitamins A and D much higher in the yellower butter of the pastured animals but the health of the people who subsisted on those animals was better too. Price believed the quality of the soil was a key to health, and in 1932, he published a paper titled “New Light on Some Relationships Between Soil Mineral Deficiencies, Low Vitamin Foods, and Some Degenerative Diseases.”
In making such connections between the quality of soil and grass and the health of the human eaters at the top of the food chain, Price was advancing a critique of the industrialized agriculture just getting established in the thirties. In this he was not alone: Around the same time, the English agronomist Sir Albert Howard, the philosophical father of the organic farming movement, was also arguing that the industrialization of agriculture-in particular the introduction of synthetic nitrogen fertilizer, which simplified the chemistry of the soil-would eventually take its toll on our health. Howard urged that we regard “the whole problem of health in soil, plant, animal and man as one great subject.” When Howard wrote these words, this was still little more than a working hypothesis; Weston Price had begun to put some empirical foundations beneath it.
Price was inching toward an ecological understanding of diet and health that was well ahead of his time. He understood that, ultimately, eating linked us to the earth and its elements as well as to the energy of the sun. “The dinner we have eaten tonight,” he told his audience in a 1928 lecture, “was a part of the sun but a few months ago.” Industrial food both obscured these links and attenuated them. In lengthening the food chain so that we could feed great cities from distant soils, we were breaking the “rules of nature” at least twice: by robbing nutrients from the soils the foods had been grown in and then squandering those nutrients by processing the foods. Compared to the native peoples Price studied, many of whom took pains to return nutrients to the local soil on which they absolutely depended, “our modern civilization returns exceedingly little of what it borrows. Vast fleets are busy carrying the limited minerals of far-flung districts to distant markets.” Renner documents how Price eventually came to see the problem of diet and health as a problem of ecological dysfunction. By breaking the links among local soils, local foods, and local peoples, the industrial food system disrupted the circular flow of nutrients through the food chain. Whatever the advantages of the new industrial system, it could no longer meet the biochemical requirements of the human body, which, not having had time to adapt, was failing in new ways.
Whether or not you’re willing to travel quite that far with Dr. Price, he and all the other early twentieth-century explorers of the pre-Western diet returned to civilization with the same simple and devastating piece of news, one that seems hard to deny: The human animal 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.
As it happened, the ecological critique of industrial civilization tha
t Weston Price was advancing in the thirties would not survive World War II. The space for such writing-occupied also by Sir Howard and Lord Northbourne in England and the American agrarians-closed down very shortly after Price published Nutrition and Physical Degeneration in 1939. People would soon lose their patience for attacks on “industrial civilization,” that being precisely what they were depending on to save them in wartime. By the time the war ended, that industrial civilization had consolidated its hold and in the process become much more sure of itself. In the years immediately after the war, industrial agriculture (which benefited from the peacetime conversion of munitions to chemical fertilizer and nerve gas research to pesticides) also consolidated its position; there would soon be no other kind. Weston Price and his fellow students of the Western diseases were largely forgotten. No one was much interested in looking back or celebrating the wisdom of primitive groups that were themselves quickly disappearing or being assimilated; even the Aborigines were moving to the city.
As for the Western diseases, they hadn’t gone away-indeed, rates of heart disease exploded immediately after the war-but now they became the responsibility of modern medicine and reductionist science. Nutritionism became the accepted set of terms in which to conduct all conversations about diet and health. It wouldn’t be until the late 1960s, with the rise of organic agriculture, that searching questions about the industrial food chain would be posed again.
THREE - THE INDUSTRIALIZATION OF EATING: WHAT WE DO KNOW
I ’ve dwelled on the all-but-forgotten ideas of people like Weston Price and Sir Albert Howard-ecological thinkers about the human food chain-because they point us down a path that might lead the way out of the narrow, and ultimately unhelpful, confines of nutritionism: of thinking about food strictly in terms of its chemical constituents. What we need now, it seems to me, is to create a broader, more ecological-and more cultural-view of food. So let us try.
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. A gradual process of mutual adaptation transforms something like an apple or a squash into a nutritious and tasty food for an animal. Over time and through trial and error, the plant becomes tastier (and often more conspicuous) in order to gratify the animal’s needs and desires, while the animal gradually acquires whatever digestive tools (enzymes, for example) it needs to make optimal use of the plant.
Similarly, the milk of cows did not start out as a nutritious food for humans; in fact, it made them sick until people who lived around cows evolved the ability to digest milk as adults. The gene for the production of a milk-digesting enzyme called lactase used to switch off in humans shortly after weaning until about five thousand years ago, when a mutation that kept the gene switched on appeared and quickly spread through a population of animal herders in north-central Europe. Why? Because the people possessing the new mutation then had access to a terrifically nutritious new food source and as a consequence were able to produce more offspring than the people who lacked it. This development proved much to the advantage of both the milk drinkers and the cows, whose numbers and habitat (and health) greatly improved as a result of this new symbiotic relationship.
Health is, among other things, the product of being in these sorts of relationships in a food chain-a great many such relationships in the case of an omnivorous creature like man. It follows that when the health of one part of the food chain is disturbed, it can affect all the other creatures in it. If the soil is sick or in some way deficient, so will be the grasses that grow in that soil and the cattle that eat the grasses and the people who drink the milk from them. This is precisely what Weston Price and Sir Howard had in mind when they sought to connect the seemingly distant realms of soil and human health. Our personal health cannot be divorced from the health of the entire food web.
In many cases, long familiarity between foods and their eaters leads to elaborate systems of communication up and down the food chain so that a creature’s senses come to recognize foods as suitable by their taste and smell and color. Very often these signals are “sent” by the foods themselves, which may have their own reasons for wanting to be eaten. Ripeness in fruit is often signaled by a distinctive smell (an appealing scent that can travel over distances), or color (one that stands out from the general green), or taste (typically sweet). Ripeness, which is the moment when the seeds of the plant are ready to go off and germinate, typically coincides with the greatest concentration of nutrients in a fruit, so the interests of the plant (for transportation) align with those of the plant eater (for nutriment). Our bodies, having received these signals and determined this fruit is good to eat, now produce in anticipation precisely the enzymes and acids needed to break it down. Health depends heavily on knowing how to read these biological signals: This looks ripe; this smells spoiled; that’s one slick-looking cow. This is much easier to do when you have long experience of a food and much harder when a food has been expressly designed to deceive your senses with, say, artificial flavors or synthetic sweeteners. Foods that lie to our senses are one of the most challenging features of the Western diet.
Note that these ecological relationships are, at least in the first instance, between eaters and whole foods, not nutrients or chemicals. Even though the foods in question eventually get broken down in our bodies into simple chemical compounds, as corn is reduced mostly to simple sugars, the qualities of the whole foods are not unimportant. The amount and structure of the fiber in that corn, for example, will determine such things as the speed at which the sugars in it will be released and absorbed, something we’ve learned is critical to insulin metabolism. The chemist will tell you the starch in corn is on its way to becoming glucose in the blood, but that reductive understanding overlooks the complex and variable process by which that happens. Contrary to the nutrition label, not all carbohydrates are created equal.
Put another way, our bodies have a long-standing and sustainable relationship to corn that they do not have to high-fructose corn syrup. Such a relationship with corn syrup might develop someday (as people evolve superhuman insulin systems to cope with regu�
�lar floods of pure fructose and glucose*), but for now the relationship leads to ill health because our bodies don’t know how to handle these biological novelties. In much the same way, human bodies that can cope with chewing coca leaves-a longstanding relationship between native people and the coca plant in parts of South America-cannot cope with cocaine or crack, even though the same active ingredients are present in all three. Reductionism as a way of understanding food or drugs may be harmless, even necessary, but reductionism in practice-reducing food or drug plants to their most salient chemical compounds-can lead to problems.
Looking at eating, and food, through this ecological lens opens a whole new perspective on exactly what the Western diet is: a radical and, at least in evolutionary terms, abrupt set of changes over the course of the last 150 years, not just to our foodstuffs but also to our food relationships, all the way from the soil to the meal. The rise of the ideology of nutritionism is itself part of that change. When we think of a species’ “environment,” we usually think in terms of things like geography, predators and prey, and the weather. But of course one of the most critical components of any creature’s environment is the nature of the food available to it and its relationships to the species it eats. Much is at stake when a creature’s food environment changes. For us, the first big change came ten thousand years ago with the advent of agriculture. (And it devastated our health, leading to a panoply of deficiencies and infectious diseases that we’ve only managed to get under control in the last century or so.) The biggest change in our food environment since then? The advent of the modern diet.