Increased raspberry intake improves blood sugar control in those with prediabetes, according to research published in Obesity. Researchers supplied frozen raspberries to 32 participants and compared 1 cup, 2 cups, and no raspberries consumed and tracked insulin resistance. Those who consumed 2 cups of raspberries saw the most improvement in blood sugar control when compared to those who consumed fewer or no raspberries. The authors suspect increased fiber intake resulted in the improvements. These results suggest improved management and prevention of diabetes with diet.