When a person has diabetes, his or her body can't control the amount of glucose (sugar) in the blood. Glucose comes from food and helps cells grow and get energy.
Normally, people have a good supply of a hormone called insulin, which moves glucose from the blood into other parts of the body. But people with diabetes either don't make enough insulin (Type 1 diabetes) or have a problem using what they have (Type 2).
Type 1 diabetics must take insulin shots every day. Why shots? In pill form, insulin would be digested before it reached the bloodstream.
Type 2 diabetics sometimes take insulin, but can control their disease by losing weight, exercising and eating healthier.