1) A disease in which the body does not properly control the amount of sugar in the blood. As a result, the level of sugar in the blood is too high. This disease occurs when the body does not produce enough insulin or does not use it properly.

2) Diabetes mellitus is a disease characterized by an inability to make or use the hormone insulin. Insulin is needed by cells to metabolize glucose, the body's main source of chemical energy. Type I diabetes, also called insulin-dependent diabetes mellitus, is usually caused by an autoimmune destruction of insulin-producing cells. Type II diabetes, also called non-insulin-dependent diabetes mellitus, occurs when cells become resistant to the effects of insulin.