You may not think of oatmeal as a superfood, but it can help reduce the risk of developing type 2 diabetes. Oatmeal contains high amounts of magnesium, which helps the body use glucose and secrete insulin properly. An eight-year trial showed a 19 percent decrease in type 2 diabetes' risk in women with a magnesium-rich diet, and a 31 percent decreased risk in women who regularly ate whole grains.