Diabetes is a long-term (chronic) condition caused by too much glucose (sugar) in the blood. It is also known as diabetes mellitus. There are two types of diabetes - type 1 and type 2.
More than three-quarters of people with diabetes have type 2 diabetes mellitus. The number of people with type 2 diabetes is rapidly increasing as it commoner in the overweight and obese, which is itself a growing problem.
The remainder have type 1 diabetes mellitus, which used to be known as insulin-dependent diabetes mellitus.