Diabetes is a serious, lifelong condition that affects an estimated 18.2 million people in the United States. It occurs when the body does not make insulin or does not use insulin properly, which results in high glucose levels in the blood. There are three main types of diabetes, including type 1, type 2, and gestational diabetes. It is important to manage your diabetes effectively, as untreated diabetes can ultimately lead to strokes, kidney failure, and blindness.