Causes
A predisposition for type 1 diabetes can be inherited, but no one knows how exactly it's passed on. Different environmental factors are likely involved, and they probably determine whether the disease develops or not. While the exact cause of type 1 diabetes isn't known, researchers believe the disease develops when a virus or toxin damages the pancreas or causes the body's immune system to attack the pancreas (called an autoimmune reaction). As a result, the cells of the pancreas can no longer produce enough insulin. Without insulin, glucose in the blood can't enter the cells in the body and blood glucose levels rise. The body begins breaking down fat and protein for energy instead of using glucose for energy.