Diabetes develops when the amount of sugar in your blood becomes too high. This is either because your body doesn’t make enough insulin (type 1 diabetes), or because your body has developed resistance to the insulin it makes (type 2 diabetes).
When your body digests food, it converts much of it into glucose. Glucose is a sugar that your body’s cells need for energy. The hormone insulin helps your body use glucose, and also helps maintain healthy blood levels of glucose. When your body produces too little insulin, or can’t respond to it, glucose tends to remain in your bloodstream, instead of going into your cells.