People who have diabetes have difficulty converting food into energy. There are three main types of diabetes, including type 1, type 2, and gestational diabetes. Possible symptoms include blurred vision, excessive thirst, and sores that do not heal properly. People who are overweight or have a family history of diabetes are at an increased risk of developing this chronic condition. If this health condition is a concern for you, your healthcare provider can check for it using a blood glucose test.