Dr. Ramon Estruch of the Department of Internal Medicine, Hospital Clinic, in Barcelona, Spain, Dr. Martinez-Gonzalez at the Department of Preventive Medicine and Public Health, Clinica Universidad de Navarra, and colleagues said those on the Mediterranean diet lowered their risk of stroke without counting calories.
The Spanish researchers said the study involved 7,447 study participants, who were allowed to consume as many calories as they wished, and were given no instructions about exercise.
The study participants were randomly assigned to one of three diets: a Mediterranean diet -- produce, nuts, olive oil, fish and poultry, but little dairy, red or processed meat or sweets, supplemented with olive oil; a Mediterranean diet supplemented with nuts; or a low-fat diet, including bread, potatoes and pasta.
The researchers tracked the participants, ages 55-80, for nearly five years. Everyone had a high risk for heart disease, but no cardiovascular problems at the time the study began.
The study, published in the New England Journal of Medicine, found compared to those told to eat a low-fat diet, those on an olive-oil rich Mediterranean diet had a 33 percent lower stroke risk, while those eating a Mediterranean diet with extra nuts had a 46 percent lower risk of stroke.