The study, published by the New England Journal of Medicine,
was experimented on 4,479 people in Spain -- men and women age 55 to 80 -- over
a five year period, finding dramatic confirmation of previous observations of
such a diet's health benefits, AFP reported.
"We observed that an energy unrestricted Mediterranean
diet, supplemented with extra virgin olive oil or nuts, resulted in a
substantial reduction in the risk of major cardiovascular events among
high-risk persons," the study concluded.
It put the risk reduction at "approximately 30 percent,
among high risk persons who were initially free of cardiovascular disease.
These results support the benefits of the Mediterranean diet for cardiovascular
risk reduction."
Ramon Estruch, a professor of medicine at the University of
Barcelona conducting this study, divided the participants into three groups
including a control group on a low fat diet.
One group followed a traditional Mediterranean diet
supplemented by four tablespoons of extra-virgin olive oil a day. A second
group followed the same diet, but instead of the olive oil consumed about 30
grams a day of mixed nuts. Participants in those two groups also ate at least
three servings of fruits and two of legumes a day. They also ate fish three
times a week and favored white meat like chicken instead of red meat.
They were also strongly encouraged not to eat commercially
baked goods, pastries and sweets, and to limit their consumption of dairy
products and processed meats. For those who normally drank wine with their
meals, their diet called for seven glasses of wine a week.
Researchers based their hypothesis on the measuring markers for olive oil in the participants
urine or blood samples for the mixed
nuts. They found that participants stuck to the Mediterranean diets, but that
the low-fat control diet led to only small reductions in fat.
"The interventions were intended to improve the overall
dietary pattern, but the major between-group differences involved the
supplemental items," the study said.
"Thus, extra virgin olive oil and nuts were probably
responsible for most of the observed benefits of the Mediterranean diets,"
it said.