Strong evidence indicates that sugar-sweetened soft drinks contribute to the development of diabetes. The Nurses’ Health Study explored this connection by following the health of more than 90,000 women for eight years. The nurses who said they had one or more servings a day of a sugar-sweetened soft drink or fruit punch were twice as likely to have developed type 2 diabetes during the study than those who rarely had these beverages. (52) Learn more about diabetes.