$1 Billion Worth of Research Later: Eating Fat Does *Not* Harm Health

“Few public health messages are as powerful and as persistent as this one: Fat is bad…The average American has substantially reduced the percentage of calories that she or he gets from fat over the past three decades…But we are not any healthier for all of this effort. In fact, we are worse off for it.” – W.C. Willett, Harvard Medical School

“[The ‘fear fat’ myth] is one of the greatest and most harmful misconceptions in the history of medicine.” – U. Ravnskov, MD, PhD

In the last post we covered a brief history of our government’s dietary guidelines (Food Guide Pyramid, MyPyramid, MyPlate, etc.). Looking at that disturbing past and our equally disturbing present, we have to ask: “What would cause our government to recommend we reduce our intake of natural foods so we can increase our intake of unnatural lower-fat foods?” Interestingly, the question is not “what” but “who?

Before the Senate’s Dietary Goals (1976) that lead to the Dietary Guidelines (1980), the Food Guide Pyramid (1992), MyPyramid (2005), and finally MyPlate (2011), there was Ancel Keys (1950s).

Keys examined diet and heart disease trends in twenty-two countries. He was apparently more interested in headlines than science because he then published a study that included data from only the six countries that showed a scary link between diet and heart disease. Keys garnered a massive amount of press and then went on tour preaching that eating fat is deadly.

Here are the facts: When the data from all twenty-two countries in Keys’ study is examined, they show no relationship between fat intake and heart disease deaths. Keys selectively picked data and designed a headline-worthy conclusion. In the words of a fellow researcher:

“No information is given by Keys on how or why the six countries were selected.”

Further exposing the sketchiness of Keys’ methods, those same researchers revealed that by selectively choosing six different countries from Keys’ data, they could create a graph suggesting that eating more fat decreases the risk of dying from heart disease.

Heart Disease Deaths per 1,000 Men

(Finland, Australia, Ireland, Switzerland, Germany, and the Netherlands)

Finally, looking at Keys’ data a few years later, they concluded, “The examination of all available basic data…show that the association [between fat and heart disease] lacks validity.” They also discovered “a strong negative association…for both animal protein and fat with mortality from non-cardiac diseases.” Even the American Medical Association spoke up in protest:

“The anti-fat, anti-cholesterol fad is not just foolish and futile…it also carries some risk.”

No matter. A sensationalized myth gets more press than a common sense fact. The “fat is evil” myth spawned a nationwide campaign to replace natural foods containing fat with fat-free edible products and climaxed with the government’s Dietary Guidelines, Food Guide Pyramid, MyPyramid, and MyPlate diets. Those diets are high in starch because starch is low in fat. Unfortunately, over a billion dollars’ worth of studies have failed to prove these diets good for anything other than profits.

“It is now increasingly recognized that the low-fat campaign has been based on little scientific evidence and may have caused unintended health consequences.” –F.B. Hu, Harvard University

“Current trends in health promotion emphasize reducing dietary fat intake. However, as dietary fat is reduced, the dietary carbohydrate content typically rises and…is frequently accompanied by an elevation of plasma triacylglycerol [a proven risk factor for heart disease]” – E.J. Parks, University of Minnesota

“Public health recommendations for the U.S. population in 1977 were to reduce fat intake to as low as 30% of calories to lower the incidence of coronary artery disease. These recommendations resulted in a compositional shift in food materials throughout the agricultural industry, and the fractional content of fats was replaced principally with carbohydrates. Subsequently, high-carbohydrate diets were recognized as contributing to the lipoprotein pattern that characterizes atherogenic dyslipidemia and hypertriacylglycerolemia [poor health].” – J.B. German, University of California

  • When P.W. Siri-Tarino of the Children’s Hospital & Research Center in Oakland examined 21 studies which included a total of 347,747 people, he found: “There is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of heart disease or cardiovascular disease.”
  • The National Heart, Lung, and Blood Institute funded an enormous trial designed to link the consumption of foods containing fat to heart disease. The $115 million Multiple Risk Factor Intervention Trial took 12,866 men with high cholesterol, split them into two groups, and fed one group the government guidelines’ diet for seven years with the hopes of lowering the incidence of heart disease. The government’s diet resulted in a 7.1% increase in heart disease deaths.
  • The Women’s Health Initiative of the National Institutes of Health completed a $700 million study to test the fat hypothesis. A whopping 48,835 women ate their normal diet or the government diet for about eight years. At the end of the study, the regular- and government-diet women weighed the same and no differences were found in their health. The researchers concluded: “Dietary intervention that reduced total fat intake did not significantly reduce the risk of coronary heart disease, stroke, or cardiovascular disease.” As reported in the study: “[This] trial is the largest long-term randomized trial of a dietary intervention ever conducted to our knowledge, and it achieved an 8.2% reduction…in total fat intake…No significant effects on incidence of coronary heart disease or stroke were observed.” The New York Times ran the headline: Low-Fat Diet Does Not Cut Health Risks, Study Finds.
  • A massive study named MONICA involved 113 groups of scientists and doctors in twenty-seven countries studying everything they thought could contribute to heart disease. They found little if any association between the average cholesterol level and heart-related mortality.
  • In The Western Electric Study—known in academic circles as one of “the most informative prospective studies to date”—researchers concluded: “Although the focus of dietary recommendations is usually a reduction of saturated fat intake, no relation between saturated fat intake and risk of coronary heart disease was observed [in their study].”

There’s no shortage of data. In the Malmö Diet and Cancer Study, 28,098 men and women were split into four groups according to their intake of foods containing fat. After six years of observation, researchers found: “Individuals receiving more than 30% of their total daily energy from fat and more than 10% from saturated fat, did not have increased mortality. Current dietary guidelines concerning fat intake are thus generally not supported by our observational results [data].” Additionally: “With our results added to the pool of evidence from large-scale prospective cohort studies on dietary fat, disease and mortality, traditional dietary guidelines concerning fat intake are thus generally not strongly supported.” And the icing on the cake: “No deteriorating effects of high saturated fat intake were observed for either sex for any cause of death.”

I’ll briefly point out three more studies: the Nurses’ Health Study, the Health Professionals Follow-Up Study, and the Nurses’ Health Study 2. Together these studies tracked 300,000 people. None of these studies showed total fat intake increasing the risk of heart disease. The only conclusive finding was that eating more plant fats—such as the fats in flax seeds and nuts—lowers the risk of heart disease. The researchers involved reported:

“Intake of linolenic acid [unsaturated fat] was inversely associated with risk of myocardial infarction [heart attacks]…These data do not support the strong association between intake of saturated fat and risk of coronary heart disease suggested by international comparisons.”

References

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