Diabetes is a condition in which the body does not make enough insulin or the body cells cannot use insulin properly. Insulin is a hormone that helps the body use glucose (sugar) for energy. Without insulin, glucose, which is the body's main energy source, builds up in the blood.
Diabetes is a disease that can have serious effects on your body, and many of those effects are permanent. If left untreated, diabetes can lead to heart and kidney disease, amputations, blindness and other serious problems. Each year about 3 million people who have diabetes are admitted to the hospital.