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Fat or Carbs: Which Is Worse?: A Response

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Dr. Andrew Weil's article has led his readers to believe that saturated fats in the diet, which are primarily from meats and dairy products, are better for them to eat than carbohydrates, which are from plant foods. He bases this on a March 2010 analysis that was "published in the American Journal of Clinical Nutrition (that) found that "saturated fat was not associated with an increased risk" of coronary heart disease, stroke or coronary vascular disease." In his opinion this piece of research is a significant exoneration of the dietary saturated fat theory for the cause of heart disease. He failed to mention that the National Dairy Council funded this study.

Furthermore, the formulation of Dr. Weil's revolutionary opinion on the wisdom of eating a diet high in animal foods appears to have been uninfluenced by an accompanying editorial written by the legendary authority on diet and heart disease, Jeremiah Stamler, MD. Dr. Stamler debunked this dairy-industry-funded study based on its flawed methodology, and a disregard of 50 years of diet-heart research with contrary findings, and dozens of metabolic (ward-type-feeding) experiments showing that eating saturated fat and/or cholesterol causes an adverse effect on blood lipids. In addition, thousands of relevant animal studies on the damaging effects of saturated fat and cholesterol were ignored.

In this article, Dr. Weil claims carbohydrates are the real culprits, and he bases this in part on an April 2010 article from the Journal of the American Medical Association. This population study found that increasing added dietary sugars from less than 5 percent to more than 25 percent of the calories (a five-fold or more change) caused a small increase in triglycerides (by nine points, from 105 mg/dL to 114 mg/dL), with a similar small reduction in good cholesterol (HDL-C) (11 points, from 58.7 to 47.7 mg/dL). Most important to notice is the large amounts of "unhealthy" carbohydrates (table sugar) that must be consumed for even small changes in blood lipids to be noticed.

In highly controlled experiments, in order to show a rise in triglycerides, the experimental design has to be based on feeding the subjects large amounts of refined sugars and flours, and/or the subjects in the experiments are required to eat more food than they can comfortably consume; in other words, they are forced to overeat. Confirmation of the healthfulness of carbohydrates is seen when people are fed starches, such as whole grains, beans, potatoes and green and yellow vegetables, rather than overfed sugars and flours; their triglyceride levels do not increase.

Dr. Weil's position runs contrary to several irrefutable observations that you can make for yourself. Starches have fueled the engines of human civilizations for at least the past 14,000 years. Carbohydrates (starches), such as rice in Asia, corn in Central America, potatoes in South America, and barley and wheat in Europe, have provided the bulk of the calories for almost all human diets. Only a few small primitive populations, living at the extremes of the environment, such as the Inuit (Eskimos), have been fueled by saturated fats. Just as undeniable, worldwide today populations of people who consume the greatest amounts of carbohydrate are the trimmest and fittest, and also have the lowest incidence of heart disease and diabetes. This truth is confirmed by observing the change that occurs when people from Japan, for example, migrate to the United States or Europe. As they eat less rice (carbohydrate) and more saturated fat (meat and dairy products) they become fatter and sicker.

Pointing the guilty finger away from fat and towards carbohydrates is self-serving for those diet experts who themselves refuse to give up their high-fat diet. Food industries buy scientific research published in respectable journals because it is one of their most effective marketing tools. The end result of this mixing up of the truth could be that billions of people will be deprived of a real opportunity to live long, disease-free lives.

John McDougall, MD

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