Okinawans, a group living on a small island in southern Japan, eat a traditional diet that is almost 85 percent starch. Both groups eat mostly sweet potatoes. With virtually no sugar or refined grains such as flour,27 type 2 diabetes is almost non-existent. The native diet of Kitava, a small island off New Guinea, consists of 69 percent carbohydrates, mostly tubers (sweet potato, cassava, and yam), coconut, and fruit, but their average insulin level is lower than 90 percent of Swedes.28
