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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 load” is the glycemic index of a food times its carbohydrate content. It is this high-glycemic load that elevates blood insulin levels in many people. High-glycemic carbohydrates cause large and rapid rises in blood glucose and have been implicated in a wide variety of chronic diseases—adult-onset diabetes, high blood pressure, heart disease, obesity, elevated blood uric acid levels, elevated blood triglycerides (the building blocks of fat, which float around in the bloodstream), elevated small-dense LDL cholesterol, and reduced HDL cholesterol. This cluster of diseases is known to cardiologists as metabolic syndrome. Regrettably, the architects of the Food Pyramid did not distinguish between high- and low-glycemic carbohydrates when they started this carbomania.
    Let’s see how our modern way of eating has deviated from the Seven Keys to nutrition I laid out in chapter 2, and how this has affected our health.

The Seven Major Problems in the Typical American Diet
1. Not Enough Protein
    Protein makes up 15 percent of the calories that most Americans (and people in other Western countries) eat every day. But it should be much higher—between 19 and 35