But before you go reaching for the nuts, adding this number of calories to a typical Western isn't what the research had in mind, and in fact would tend to lead to weight gain and increased disease risk.

The American Heart Association estimates that 50 million U.S. adults have metabolic syndrome and this greatly increases our risk of heart disease.

Metabolic syndrome is a combination of factors that include high blood pressure, abdominal obesity, high triglycerides, low good cholesterol and high blood sugar.

Earlier studies have suggested that the Mediterranean style diet may reduce the risk of metabolic syndrome, and the team of Spanish researchers wanted to test the effectiveness of this type of diet plan verses a low fat diet.

Mediterranean style diets are rich in fruits, vegetables and fish. They don't include lots of red meat or dairy products.

Study lead author Dr. Jordi Salas-Salvado of the University of Rovira i Virgili in Reus, Spain says that eating nuts gives you a full feeling, while also improving the fat burning abilities of the body.

Salas-Salvado and another co-author are unpaid advisers to nut industry groups, though their work was reviewed and accepted by a peer-reviewed journal.

The team points out that nuts are also rich in anti inflammatory substances and antioxidants, as well as being good sources of unsaturated fat - a healthier fat that lowers triglycerides and improves levels of good cholesterol.

The research involved over 1,200 Spanish subjects aged 55 to 80 who had no prior history of heart disease, though some did have risk factors for the condition.

Participants were randomly assigned to one of three diets - a low fat diet (the control diet), a Mediterranean style diet with supplemented more than 4 tablespoons of olive oil a day, or a Mediterranean style diet that also included a handful of nuts each day.

When the study began about 61% of participants had metabolic syndrome, spread evenly across the three diet groups.

At the end of the year long study, the nut eaters didn't lose weight, but a majority of them did reduce their belly fat while also improving their blood pressure and cholesterol numbers.

The rate of metabolic syndrome improvement was 13.7% in the nut-eating group. Of the olive oil group, 6.7% had improved enough to no longer be classified as having metabolic syndrome; while in the low fat group there was little difference (less than 2%) in the percentage of those with metabolic syndrome from the beginning of the study.

“What's most surprising is they found substantial metabolic benefits in the absence of calorie reduction or weight loss,” said Dr. JoAnn Manson, chief of preventive medicine at Harvard's Brigham and Women's Hospital.

Your best bet if you're concerned about metabolic syndrome, or heart disease, is to talk with your own doctor or nutritionist about the benefits of adopting a Mediterranean style diet.

Making small changes like reducing how much red meat you eat, cutting out some of the saturated fats, limiting the junk food and upping the amount of fruits, veggies and fish are solid first steps. Taken alongside the nuts nutrition facts the study discovered, and add a few nuts each day, and you could be keeping your body, and your heart, healthy for years to come.