Article

The origin of low-fat diet. The fallacy of the lipidic hypothesis

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Abstract

For over 30 years, healthy eating has been synonymous with eating a low-fat diet. Since the 1950's, and due to the influence of Dr. Ancel Keys, dietary fat in particular saturated fat, has been thought to be responsible for the high levels of cardiovascular disease affecting populations with Western lifestyles. The reduction of saturated fat in the diet is based on the lipidic hypothesis, which puts forward the idea that a reduction in the consumption of saturated fat lowers plasmatic cholesterol levels and consequently the rate of heart disease. Many scientific societies and even government institutions have adopted this hypothesis in order to make dietary recommendations that stigmatize animal fat, especially that from meat. However, scientific evidence that has emerged from epidemiological studies and clinical trials has not demonstrated that saturated fat increases the risk of cardiovascular disease. Yet, a low-fat diet, known as a cardio-diet which is composed mainly of carbohydrates, which amount to 50% of its energetic value, and no more than 10% of saturated fats, has become widespread and is currently regarded as a model for healthy eating.

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... Despite an abundance of anecdotal evidence and scientific research on the therapeutic advantages of KD, there is still flourishing myths about it as being unsustainable and unsafe. Several aspects promote this situation, such as persistent propaganda of low fat [58], lack of nutritional training in medical educational programs, overreliance on pharmacotherapy in choice of scientific research topics, and lack of practical tools to promote education and lifestyle change for the sick persons. ...
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NUTRITIONMainstream nutritional science has demonized dietary fat, yet 50 years and hundreds of millions of dollars of research have failed to prove that eating a low-fat diet will help you live longer. Indeed, the history of the national conviction that dietary fat is deadly, and its evolution from hypothesis to dogma, is one in which politicians, bureaucrats, the media, and the public have played as large a role as the scientists and the science. It's a story of what can happen when the demands of public health policy--and the demands of the public for simple advice--run up against the confusing ambiguity of real science.
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