Type 1 Diabetes

In people with type 1 diabetes, the pancreas stops making insulin. No one is exactly sure why this happens. Doctors think the beta cells get attacked by other cells (called T-cells) that are programmed to protect your body. The T-cells are like a little army, marching through your body, finding invaders that cause illness, and fighting them. When you have the flu, the T-cells find the flu bug in your body, and attack it until you're healthy again. When the T-cells work right, they keep you healthy.

In people with type 1 diabetes, the T-cells get confused. They think the beta cells are germs that make you sick. So they try to protect you by attacking them. When that happens, the pancreas can no longer make insulin.