Monday, February 25, 2013

Low-fat diet causes heart disease

The NY Times reports on a major new diet study:
About 30 percent of heart attacks, strokes and deaths from heart disease can be prevented in people at high risk if they switch to a Mediterranean diet rich in olive oil, nuts, beans, fish, fruits and vegetables, and even drink wine with meals, a large and rigorous new study has found.

The findings, published on The New England Journal of Medicine’s Web site on Monday, were based on the first major clinical trial to measure the diet’s effect on heart risks. The magnitude of the diet’s benefits startled experts. The study ended early, after almost five years, because the results were so clear it was considered unethical to continue.

The diet helped those following it even though they did not lose weight and most of them were already taking statins, or blood pressure or diabetes drugs to lower their heart disease risk. ...

Low-fat diets have not been shown in any rigorous way to be helpful, and they are also very hard for patients to maintain — a reality borne out in the new study, said Dr. Steven E. Nissen, chairman of the department of cardiovascular medicine at the Cleveland Clinic Foundation.

“Now along comes this group and does a gigantic study in Spain that says you can eat a nicely balanced diet with fruits and vegetables and olive oil and lower heart disease by 30 percent,” he said. “And you can actually enjoy life.”
The physicians havee been telling us for 40 years that a low-fat diet is the best way to prevent heart disease. This is the latest study that shows just the opposite.

The study compared a low-fat diet to two other diets, for Spaniards at high risk for heart disease. Those on the low-fat diet did significantly worse. It appears that they really wanted to compare olive oil to nuts, but found no difference.

The NEJM paper argues:
Our results compare favorably with those of the Women's Health Initiative Dietary Modification Trial, wherein a low-fat dietary approach resulted in no cardiovascular benefit.35 Salient components of the Mediterranean diet reportedly associated with better survival include moderate consumption of ethanol (mostly from wine), low consumption of meat and meat products, and high consumption of vegetables, fruits, nuts, legumes, fish, and olive oil.36,37 Perhaps there is a synergy among the nutrient-rich foods included in the Mediterranean diet that fosters favorable changes in intermediate pathways of cardiometabolic risk, such as blood lipids, insulin sensitivity, resistance to oxidation, inflammation, and vasoreactivity.38
Perhaps there is a synergy?! In other words, this study tells us nothing about the advantages of individual aspects of the Mediterranean diet, such as olive oil and wine. It only confirms previous studies that the low-fat diet does not help.

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