A recent trial in the Annals of Internal Medicine looked at the role of a Mediterranean diet in reducing the onset of type 2 diabetes. It seems to suggest that eating this type of diet which is especially high in extra virgin olive oil (50ml/day) in some way prevents the onset of diabetes. The benefit was a 30% risk reduction in developing diabetes compared to controls who were on a low fat diet. The diet was relatively low in dairy products and low in carbohydrate content.
Although the mechanism of how the Mediterranean diet reduces the onset of diabetes is not completely understood it may be related to the relatively low carbohydrate content and the prevention of insulin resistance.
This is not conclusive evidence but it does suggest that a Mediterranean diet is better for us and in particular reducing the carbohydrate content in our diets is a good thing.
Ann Intern Med January 6 2014 http://annals.org