In Defense of Food

Michael Pollan is a great writer, and In Defense of Food is my second favorite of his books (The Botany of Desire is my favorite).  This book helped further cement my view that the typical western diet is terrible. This case study summarized by Pollan is illuminating:

The Aborigines divided their seven-week stay in the bush between a coastal and an inland location. While on the coast, their diet consisted mainly of seafood, supplemented by birds, kangaroo, and witchetty grubs, the fatty larvae of a local insect. Hoping to find more plant foods, the group moved inland after two weeks, settling at a riverside location. Here, in addition to freshwater fish and shellfish, the diet expanded to include turtle, crocodile, birds, kangaroo, yams, figs, and bush honey. The contrast between this hunter-gatherer fare and their previous diet was stark: O’Dea reports that prior to the experiment “the main dietary components in the urban setting were flour, sugar, rice, carbonated drinks, alcoholic beverages (beer and port), powdered milk, cheap fatty meat, potatoes, onions, and variable contributions of other fresh fruits and vegetables”—the local version of the Western diet. After seven weeks in the bush, O’Dea drew blood from the Aborigines and found striking improvements in virtually every measure of their health. All had lost weight (an average of 17.9 pounds) and seen their blood pressure drop. Their triglyceride levels had fallen into the normal range. The proportion of omega-3 fatty acids in their tissues had increased dramatically. “In summary,” O’Dea concluded, “all of the metabolic abnormalities of type II diabetes were either greatly improved (glucose tolerance, insulin response to glucose) or completely normalized (plasma lipids) in a group of diabetic Aborigines by a relatively short (seven week) reversion to traditional hunter-gatherer lifestyle.”

I was amazed to learn how much four key seeds (corn, soy, wheat, and to a lesser extent rice) dominate the western diet, and how the general shift from eating leaves to eating seeds has ruined our health:

Corn contributes 554 calories a day to America’s per capita food supply and soy another 257. Add wheat (768 calories) and rice (91) and you can see there isn’t a whole lot of room left in the American stomach for any other foods… Of all the changes to our food system that go under the heading “The Western Diet,” the shift from a food chain with green plants at its base to one based on seeds may be the most far reaching of all. Nutritional scientists focus on different nutrients—whether the problem with modern diets is too many refined carbohydrates, not enough good fats, too many bad fats, or a deficiency of any number of micronutrients or too many total calories. But at the root of all these biochemical changes is a single ecological change. For the shift from leaves to seeds affects much more than the levels of omega-3 and omega-6 in the body. It also helps 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, if not quite, a Theory of Everything.

Towards the end of the book, Pollan offers a few simple rules for eating.  One central rule, he suggests, is to define what to eat by turning back the clock: