As long ago as 1982, the National Research Council published a report called Diet, Nutrition, and Cancer, 24 showing the evidence already available linking specific dietary factors to cancer of the breast and other organs.
Asian countries, such as Japan, have low rates of breast cancer, while Western countries have cancer rates that are many times higher. 25,26 However, when Japanese girls are raised on westernized diets, their rate of breast cancer increases dramatically.
The traditional Japanese diet is much lower in fat, especially animal fat, than the typical Western diet. In the late 1940s, when breast cancer was particularly rare, less than 10 percent of the calories in the Japanese diet came from fat. 27 The American diet, of course, is centered on animal products, which tend to be high in fat and low in other important nutrients. The fat content of the average American diet is in the range of 37 to 40 percent of calories.
Countries with a higher intake of fat, especially animal fat, have a higher incidence of breast cancer. 25,28,29 Even within Japan, affluent women who eat meat daily have an 8.5 times higher risk of breast cancer than poorer women who rarely or never eat meat. 26 The Surgeon General's Report on Nutrition and Health 30 stated: "Indeed, a comparison of populations indicates that death rates for cancers of the breast, colon, and prostate are directly proportional to estimated dietary fat intakes."
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