Type 1 diabetes is a lifelong disease that happens when the pancreas stops making insulin. It usually develops in children and young adults.
Insulin lets sugar (glucose) move from the blood into the body's cells, where it can be used for energy or stored. Without insulin, sugar can't get into the cells, and your blood sugar gets too high. Over time, high blood sugar can lead to problems with your eyes, heart, blood vessels, nerves, and kidneys.
Treatment for type 1 diabetes focuses on keeping your blood sugar level in a safe range by eating a balanced diet, taking insulin, and getting regular exercise.