The Paleo Diet - Loren Cordain [26]
The health picture got worse over the years with the arrival of salt, fatty cheeses, and butter. Our ancestors learned to ferment grains, make beer, and eventually distill spirits. Selective breeding—and the innovation of feeding grain to livestock—steadily produced fatter pigs, cows, and sheep. Most meat wasn’t eaten fresh—fewer people hunted—but instead was pickled, salted, or smoked. Fruits and vegetables became luxuries—rare seasonal additions to the monotony of cereal and starch.
More recently—just 200 years ago—the Industrial Revolution brought refined sugar, canned foods, and refined white flour to the average family’s table. Food was processed in earnest by the mid-twentieth century with the invention of trans-fatty acids, margarine, shortening, and combinations of these fats mixed with sugar, salt, other starches, high omega 6 vegetable oils, high-fructose corn syrup, and countless additives, preservatives, coloring agents, and emulsifiers.
Imagine a Paleolithic human confronted with a Twinkie or even a pizza. He or she wouldn’t even recognize these modern-day treats as food.
Big Mistakes in the 1950s
In many ways, the 1950s were a simpler time. Part of the mind-set then seemed to be to find simple solutions for complicated problems. In the early 1950s, when scientists were unraveling the links between diet and heart disease, they found that saturated fat (the kind found in butter, cheese, and fatty meats) raised total blood cholesterol; it also raised the LDL (the bad kind) cholesterol level and increased the risk of heart disease. More recent research has shown that not all saturated fats raise total and LDL cholesterol. Stearic acid actually lowers blood cholesterol similar to the way that monounsaturated fats do. Unfortunately, red meat became the scapegoat; all of a sudden, it was the chief artery clogger and cause of heart attacks. Even many nutritionists and physicians jumped to the conclusion that red meat was an unhealthy food that promoted heart disease and bowel cancer.
The food industry responded to the message that saturated fats were bad by creating all sorts of “healthy alternatives”—highly polyunsaturated vegetable oils (corn, safflower, sunflower, and cottonseed, to name a few). They also gave us all kinds of products made from these oils, such as margarines, shortening, spreads, and dressings. And almost overnight, these vegetable oils and their spin-offs were incorporated into virtually all processed foods and baked goods.
Unfortunately, as we now know, this was a very bad move. The indiscriminate infusion of vegetable oils into the American diet gave us far too many omega 6 polyunsaturated fats at the expense of the good omega 3 polyunsaturated fats. And the increased use of margarine and spreads caused the widespread introduction of still another kind of fat, called “trans-fatty acids,” into our meals and snacks.
The next plan the nutritional masterminds came up with—like the anti-red meat campaign, it was not well thought out and was inadequately tested before being put into practice—was to replace saturated fats with carbohydrates, primarily starchy carbohydrates, like those found in bread, potatoes, and cereals. By the early 1990s, this recommendation had become so entrenched that it was the official policy of the USDA. The bedrock of our national Food Pyramid is its base—six to eleven servings of cereal grains. We now know, from scientific studies examining something called the “glycemic index” of certain foods, that this is six to eleven servings too many.
Part of the confusion here is that all carbohydrates are not created equal. Some of them are good for us. But others promote ill health and disease, and this brings us to the glycemic index. Good carbohydrates have a low glycemic index. This means they cause a minimal or slow rise in our blood glucose (sugar) level. The “glycemic