We embraced the erroneous low-fat paradigm because a University of Minnesota-based expert named Ancel Keys had a gut feeling that saturated fat caused heart disease; collected carefully chosen data from dietary practices in Greece and Italy to back up his hunch, then brushed off all contrary evidence. Keys quickly developed alliances at the American Heart Association and the National Institutes of Health, on Capitol Hill and at the USDA — with the help of an eager and unquestioning health press much like that of today.
Okay, so Minnesota isn't really to blame, but rather Keys and his ilk. Scott goes on to further describe how Keys's well-meaning--but misguided--efforts to get people to eat less animal and especially saturated fat hurt rather than helped us. Many of these points come from the book "The Big Fat Surprise," by investigative reporter Nina Teicholz. She argues that the data to support a low-fat diet doesn't exist, as CNN reported:
Take the 30-year follow-up to the landmark Framingham Heart Study, for example. It is one of the largest epidemiological studies evaluating the roots of heart disease in our country. In the follow-up, scientists found that half the people who had heart attacks had below-average cholesterol levels. In fact, scientists concluded that "for each 1 percent mg/dL drop of cholesterol, there was an 11 percent increase in coronary and total mortality."
Not everybody agrees, however. Dr. Walter Willett, chairman of the department of nutrition at the Harvard School of Public Health, told CNN that replacing saturated fats with healthy fats improves blood lipids, and in turn reduces heart disease.
But both sides would probably agree that a shift from a diet high in animal fats to a diet high in simple carbohydrates like sugar--a pattern seen in the United States--isn't healthy. To make up your own mind, check out the book yourself here, and read reviews of Teicholz's tome at the Wall Street Journal, the Chicago Sun-Times, and on Amazon.com.