Women On Mediterranean-Type Diets May Lower Heart, Stroke Risk
U.S. women whose diets most closely match the traditional Mediterranean diet — high in monounsaturated fat, plant proteins, whole grains and fish — are significantly less likely to develop heart disease and stroke, researchers report in Circulation: Journal of the American Heart Association.
In a study of women who participated in the Nurses’ Health Study, those whose diets most closely resembled the Mediterranean one — compared to those whose diet least matched it — had a 29 percent reduction in heart disease risk and a 13 percent reduction in stroke risk.
Furthermore, women whose diets most closely matched the Mediterranean-style diet had a 39 percent reduction in combined coronary heart disease and stroke mortality compared to women whose diets least matched it.
“Those are dramatic results,” said Teresa T. Fung, Sc.D., lead author of the study and associate professor at Simmons College and adjunct associate professor in nutrition at the Harvard School of Public Health in Boston, Mass. “We found that women whose diets look like the Mediterranean diet are not only less likely to die from heart disease and stroke, but they are less likely to have those diseases.”
During the study’s 20 years of follow-up, researchers found 2,391 incidents of coronary heart disease, 1,763 strokes and a combined total of 1,077 fatal heart attacks and strokes.
Fung and her colleagues used data on 74,886 women ages 38–63 (in 1984) who participated in the Nurses’ Health Study, which researchers started in 1976 to examine factors that influence women’s health.
The Nurses Health Study, funded by the National Institutes of Health, is one of the largest and longest-running investigations of its kind. The current analysis averaged data from six different dietary assessment self-reported between 1984 and 2002.
Previous studies have shown an association between the Mediterranean diet and a reduced risk of cardiovascular death in both men and women. This is one of the few studies with enough participants to meaningfully examine the incidence of non-fatal cardiovascular disease or stroke individually, Fung said.
The participants’ average scores were arranged according to their similarity to the Mediterranean diet, and then divided into five groups, or quintiles.
Researchers scored the diets as most closely resembling the Mediterranean diet, although the U.S. food choices differed in many ways from those in southern Italy and Greece, where the diet has been followed traditionally. For instance, the traditional Mediterranean diet features olive oil, which is high in monounsaturated fatty acids, as the primary cooking oil. It is used rather than butter or margarine, even for dipping bread. The U.S. version of the diet would probably have more canola oil or peanut butter as sources of monounsaturated fat, researchers said.
Compared to a typical U.S. diet, the Mediterranean diet requires a shift toward a more plant-based diet, which means eating less meat and getting more of the day’s protein from plant sources like beans and nuts, she said. “It is possible that women who more closely follow the Mediterranean diet substitute whole grains, fruits and vegetables for deep fried or highly processed foods.”
“I think the Mediterranean diet is by far one of the easiest to follow because there are no extremes,” Fung said. “It does not require you to cut out something or eat only a few number of foods. The types of food common to the Mediterranean diet are pretty easy to get as well. It has a good amount of plant oils, so you are not cutting out fats. You can eat red meat, beef and pork only once or twice a month, eat fish at least once a week and eat more chicken.”
From a global perspective, Fung fears the typical U.S. diet pattern of fast food and red meat may be replacing the Mediterranean diet even in Mediterranean countries. “Fast food restaurants are becoming more common over there.”
Researchers said their results need to be replicated in other populations, especially men.