Atherosclerosis is a slow, progressive condition in which the arteries thicken with plaque build-up and can lead to a number of complications, including heart attack and stroke. By causing moderate weight loss and improving blood pressure, the three diets reversed atherosclerosis in obese people.
The participant population included 140 obese people, mostly men, who were at high risk for atherosclerosis. Each was randomly assigned to a low-carbohydrate, low-fat or Mediterranean diet, and after two years on a diet, and lost about 10 pounds on average. Using a novel noninvasive imaging method, the team found an average 5 percent regression in carotid vessel-wall volume and 1.1 percent decrease in carotid artery thickness. “This regression is a significant decrease for the two-year time span,” said Meir Stampfer, MD, DrPH, associate director of the Channing Laboratory at BWH and senior author of the study. “This implies that a healthy diet may not simply slow atherosclerosis, but can also reverse effects.”
Researchers explain that weight loss from these diets is the cause of this reversal of atherosclerosis, rather than the actual nutrients of each. However, they recognize that choosing one particular diet over another because of preference in taste may improve the likelihood of an individual’s success with the diet. The regression in vessel wall volume was attributed to the decline in blood pressure as a consequence of weight loss. The effect was most pronounced in those who lost the most weight, and who had the biggest decline in blood pressure.
Dr. Stampfer and colleagues are the first to demonstrate the utility of this novel method of evaluating the vessel wall. By using a simple ultrasound rigged to measure in three dimensions, the researchers were able gauge volume rather the just wall thickness.
The study was funded by the Israeli Ministry of Health, the Canadian Institutes of Health Research, the Heart and Stroke Foundation of Canada, and the Dr. Robert C. and Veronica Atkins Research Foundation.