Low-fat, low-carb, Mediterranean regimens all help the heart, study finds
MONDAY, March 1 (HealthDay News) -- Any one of three heart-healthy diets -- low-fat, low-carbohydrate, Mediterranean -- can reverse the thickening of artery walls that can lead to heart attack and stroke, an Israeli study indicates.
"Once one adheres to a sensible diet, even though you experience only a moderate weight loss, if you stick to it long enough you can cause regression of atherosclerosis," explained Iris Shai, a nutritional epidemiologist at Ben-Gurion University of the Negev, and lead author of a report to be published in the March 16 print issue of the journal Circulation.
Atherosclerosis involves a thickening and narrowing of blood vessels. When narrowing leads to a full blockage of blood flow, heart attacks or strokes are the result.
Shai and her colleagues assigned 140 middle-aged, overweight men and women to one of three low-calorie diets: low-fat; low-carbohydrate; or the Mediterranean diet, which emphasizes fruits, vegetables and healthy fats such as those found in olive oil.
About one-third of the participants were taking blood pressure medications and one-quarter were taking cholesterol-lowering medications, mostly statins.
The researchers tracked the participants' adherence to the recommended diet, as well as their weight and blood pressure. Using ultrasound scans to obtain three-dimensional images, the team also assessed the volume and thickness of the carotid arteries, the major vessels carrying blood to the brain.
After two years, the researchers found that dieters experienced a significant 5 percent reduction in average carotid artery wall volume and a 1.1 percent reduction in carotid wall thickness.
There were also moderate reductions in blood pressure and average weight.
"With a healthy diet and only moderate weight loss and reduction in blood pressure, you can see regression of plaque that naturally progresses over the years," Shai said.
All three diets had certain elements in common -- an increased consumption of fruits and vegetables, and decreased consumption of dangerous trans-fats, especially those found in processed foods, she said.
"The message seems to be that weight loss, no matter how you accomplish it, is good for the carotid artery," said Dr. Robert H. Eckel, professor of medicine at the University of Colorado, a past president of the American Heart Association.
While the reduction in blood pressure was perhaps the most important dietary effect, "with weight reduction many things change in the right direction," Eckel said.
Anyone undertaking to follow such a diet must be prepared to stick with it over the long run, he stressed.
"Blood pressure measured during active weight loss is bound to fall," Eckel said. "But that might not be sustained. Blood pressure must continue to be monitored, and treated to reach a goal."
Find out more about heart-healthy diets at the American Heart Association.
SOURCES: Iris Shai, Ph.D., nutritional epidemiologist, Ben-Gurion University of the Negev, Beer-Sheva, Israel; Robert H. Eckel, M.D., professor, medicine, University of Colorado, Denver; March 1, 2010, Circulation, online
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