Adopting the Mediterranean diet narrows your waist and lowers your cholesterol, triglycerides and blood pressure, a new review has found.

"The strong anti-inflammatory and antioxidant role of [the diet's] constituents are the main protective mechanism," said Dr. Demosthenes B. Panagiotakos, an associate professor of biostatics and nutrition epidemiology at Harokopio University of Athens in Greece.

A Mediterranean diet is high in monounsaturated fatty acids, which followers of the diet consume mainly as olives and olive oil. It also includes eating fruits and vegetables, whole grains and low-fat dairy products such as yogurt every day, and consuming fish, poultry, nuts and beans every week, Panagiotakos said.

People who abide by the diet also don't eat much red meat and drink a moderate amount of alcohol (one drink for women a day, two for men), he said.

Panagiotakos and his colleagues analyzed 50 studies, published through April 2010, that included 534,906 patients. Though some results varied from study to study, there was consensus: eating a Mediterranean diet improved abdominal obesity and metabolism of sugars, and lowered cholesterol levels , he said.

Taken together, these health benefits bring a lower risk of developing metabolic syndrome, the researchers said. People with this syndrome have a higher risk of developing heart disease, stroke and diabetes.

The improvements seen in the study were small for example, those on the diet had, on average, a waistline just 0.2 inches smaller than those not on the diet. Still, the effects of large groups of people being on the diet "are of considerable public health importance," the researchers said, because it's a low-cost way to lower the prevalence of metabolic syndrome.

The effects of the diet were more pronounced in Mediterranean countries than elsewhere, the study said. And those who had followed the diet for longer than three months saw more health benefits than those who'd more recently converted.

The Mediterranean diet is very easy to follow, said registered dietitian Keri Gans, a spokeswoman for the American Dietetic Association who was not involved with the study.

"What we try to emphasize is to include a variety of these foods," Gans told MyHealthNewsDaily. "You're including nuts, olive oil and seafood, and you want portion control on all of them."

It's also important to eat the wide variety of foods included in the diet to reap its maximum health benefits , she said.

While many previous studies have also found the Mediterranean diet to have health benefits, one study published in January in the International Journal of Clinical Practice cast doubt on it. The research showed that more than 60 percent of people living in Andalucia, Spain, were overweight or obese. This is a region of Spain where it's the norm to consume a Mediterranean diet, the researchers said.

However, the study's results likely stem from smoking and a lack of physical activity, Gans said.

"You can't just look at what you're eating you also have to look at what you're doing," she said.

Pass it on: Adhering to a Mediterranean diet can improve your waist size, blood pressure levels, triglycerides and cholesterol levels.

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