Now this is interesting.  According to Men’s Health magazine,

Dark colored fruits like grapes, blueberries, raisins and prunes can help reduce your risk for diabetes. A study from Harvard University found that three servings a week of these foods can slash people’s diabetes odds by as much as 12 percent because they are rich with polyphenols that may help improve glucose metabolism and sensitivity. But researchers warn that the benefit is only seen in people who eat the whole fruit. Those who drink fruit juice actually face an eight percent higher risk of diabetes.

Make sure you eat your dark fruits!!