The Mediterranean diet beats a low fat diet when it comes to preventing type 2 diabetes mellitus, according to a study published on Oct 7, 2010 on the Diabetes Care website.

The study led by Jordi Salas-Salvadó, M.D., Ph.D. from Hospital Universitari de Sant Joan in Spain shows that the Mediterranean diet supplemented with olive oil and/or nuts was associated with a 51 percent and 52 percent reduced risk of diabetes, respectively. 

When olive oil and nuts both were added to Mediterranean diet, the risk was reduced by 52 percent.

The researchers also found that increased adherence to the Mediterranean diet was inversely linked with diabetes incidence.

The study involved 418 non-diabetic subjects aged 55 to 80 years who were at high cardiovascular risk.  For a 4-year period, three groups of participants were assigned each of three dietary regimens, the Mediterranean diet with olive oil, Mediterranean diet with nuts and a low fat diet.

During the follow-up, diabetes was diagnosed in 10.1 percent of individuals in the Mediterranean diet supplemented with 1 liter of olive oil per week, 11.0 percent in the Mediterranean diet supplemented with 30 grams of nuts per day and 17.9 percent in the control group respectively.

The researchers concluded "Mediterranean diets without calorie restriction appear to be effective in the prevention of diabetes in subjects at high cardiovascular risk."

Type 2 diabetes mellitus affects an estimated 20 million Americans. There is no cure for the disease, but certain diets are known to help manage it.

By David Liu and editing by Rachel Stockton