In the incisive and entertaining In Defense Of Food: An Eater's Manifesto (Penguin, 2008), journalism professor Michael Pollan sums up his "personal eating policies" as: "Eat food. Not too much. Mostly plants."
And, sadly, the contemporary notion of food is so foggy and confused that he needs fully one-third of the book to explain and justify the difference between "real food" and "edible foodlike substances."
Most of us can distinguish, I think, between real food and junk food. But which is Sara Lee's Soft & Smooth Whole Grain White Bread, with its (approximately) 41 ingredients?
It violates a number of Pollan's rules of thumb: unpronounceable ingredients, unfamiliar ingredients, number of ingredients (more than five), the presence of high-fructose corn syrup. It "is not food and if not for the indulgence of the FDA could not even be labeled 'bread,'" Pollan writes.
For the FDA, in 1973, quietly reversed a labeling requirement stated in the 1938 Food, Drugs, and Cosmetics Act. This rule compelled labels to read "imitation" if there were any unexpected deviation from, as the Act put it, "traditional foods that everyone knows."
Pollan lists sour cream, yogurt, bacon, whipped cream, coffee creamer, and eggs that since 1973 can be and are engineered with completely non-traditional ingredients: hydrogenated oils, soy protein, corn starch. And that somehow are accepted by the consumer not simply as good as the real thing, but as the real thing. (My own personal example is the spectacle of guacamole that contains no avocado.)
Pollan's point is that industry has managed to create imitation bread, which after decades of food processing is now assumed by most people toactually be bread.
Another important point in In Defense Of Food concerns a 1984 nutrition study published in the journal Diabetes. This study demonstrated that non-Western, pre-modern diet and lifestyle could rapidly impact long-standing health problems like high blood pressure and insulin resistance.
In the study, ten diabetic Australian aborigines briefly return to a bush lifestyle. Before the study, they lived in town and only occasionally hunted; they ate a "Western diet" (white bread, sugar, etc.). During the seven-week study, accompanied by the researcher, they live in the outback hunting, fishing, and gathering traditional foods that include kangaroos, turtles, figs, and grubs. By the end of the seven weeks, all their metabolic markers improve or normalize; all have lost weight and lowered blood pressure.
Pollan reviews the historical evidence about the Western diet, noted first-hand by Western observers. As Western food became available to traditional societies in the 19th and 20th centuries, Western diseases followed: obesity, diabetes, heart disease, cancer. "The human animal is adapted to, and apparently can thrive on, an extraordinary range of different diets, but a Western diet, however you define it, does not seem to be one of them," Pollan writes.
It's become evident that the "Western diet" somehow causes "Western diseases," but harder to know what to do about it. "The challenge we face today," he writes, "is figuring out how to escape the worst elements of the Western diet and lifestyle without going back to the bush."
Pollan briefly mentions additional studies that tested "dietary patterns," such as the Mediterranean diet, rather than individual variables. Outcomes included reduced blood pressure and reduced number of heart attacks.
More such studies exist, and many people (including me) simply do their own personal experiments. It's important to know that there is an extensive literature, both formal and informal, about restoring health through diet. Michael Pollan does not cover this in detail, but his work in defense of food helps to clear up the confusion, or at least open a debate, about what food is.
See In Defense of Food at Amazon