Did the federal low fat guidelines cause obesity?

Harvard’s Dr. Eric B. Rimm:  “Dietary fats do not lead to obesity…”

On October 31, 2008, during that first meeting of the 2010 Dietary Guidelines Advisory Committee (DGAC), Dr. Eric B. Rimm, Associate Professor of Medicine, Harvard Medical School, questioned what he called the “artificial limit” on dietary fat in the U.S. Dietary Guidelines.

From the transcripts:  www.cnpp.usda.gov/DGAs2010-Meeting1.htm

Dr. Rimm: “I wanted to make a radical point, one for which I’ll probably get kicked off the stage, but the whole issue of total fat and the 20 to 35 percent of calories from fat is one that has troubled me…”

Dr. Rimm:  “… There is not one point which is the healthiest point of fat intake which is why we came up with the range. But the high end, 35 percent of calories from fat, actually was not really based on much science; it’s based on the fact that we don’t have a lot of science beyond 35 percent, and there was a concern that higher fat diets would lead to obesity.”

Dr. Rimm:  I think if you look at the science, there is actually no good human data to suggest that higher fat diets lead to obesity. If anything, higher fat diets, at 35 to 40 percent, lead to lower triglycerides because it’s a lower carbohydrate intake.

Dr. Rimm:  “… I think there is the dogma that low-fat diets are beneficial, and you can go in the grocery store and see a lot of low-fat foods that are essentially just high in carbohydrate, highly processed sugars.”

Rest assured, Dr. Rimm didn’t get “kicked off the stage” but the issue never came up again, and the final report of the 2010 Dietary Guidelines contains more stringent reductions in saturated fats and cholesterol than all previous low fat Dietary Guidelines (1980-2005) – recommending that Americans reduce saturated fat intake to just 7 percent of calories and demonizing dietary fats and animal foods rich in saturated fat such as egg yolks, butter, whole milk, cheese, and red meat.

Dr. Walter Willett

Dr. Walter C. Willett, Chairman, Department of Nutrition, Harvard School of Public Health, agreed with Rimm – his Harvard associate. In an interview with Melissa Healy in the Los Angeles Times on June 28, 2010, Dr. Willett said:    “Shortcomings of the report include the percentage of total fat is still recommended to be less than 35% of calories…”

“The best available evidence demonstrates that percent of calories from fat in a diet has no bearing on weight loss – a point the dietary guidelines committee acknowledges. It makes no sense to base the dietary guidelines on an outdated recommendation.”

You would think that the Institute of Medicine hosting the recent Washington DC summit on obesity would pay some attention to what these Harvard professors had to say. Gee, maybe fat isn’t the culprit after all? At the same time, why not critically examine whether the low fat Dietary Guidelines of the last 30 years may in fact be the root cause of obesity.