The research was done using data from the DASH trial of the 1990s, in which 459 people with elevated blood pressure not high enough to require medication were sorted into three groups. Each group ate one of three diets for eight weeks, the DASH diet, a diet rich in fruits and vegetables but otherwise comparable to a typical diet, or a more typical fatty American diet. All of the food was provided by researchers, who carefully measured out portions and determined the nutrient content of the meals being served. Using a risk assessment calculator devised by the Framingham Heart Study, Maruthur's team was able to estimate heart disease risk.

Maruthur says the reason that the diet likely reduces coronary heart disease risk is that it reduces both blood pressure and blood cholesterol levels, two independent risk factors for coronary disease.

One drawback of the study ” and most any study of lifestyle interventions ” is that it relies on estimates for determining heart disease risks in the long term. Researchers point out that it would take too much time and money to follow people for the decades required to see if the prescribed diet helps reduce actual heart attacks and heart disease deaths.

For years, doctors and policy makers have talked about the detrimental effects of the typical American diet on the nation's health. Physician, advocacy and government groups have advocated for widespread adoption of a diet similar to the DASH diet. But the message, says Maruthur, still hasn't gotten through.

"It's no secret that we should be eating less saturated fat and more fruits and vegetables," she says. "But how do we get the general population to adopt the DASH diet? The public health benefits could be enormous."

Source : Johns Hopkins University School of Medicine