Diabetes mellitus, commonly referred to as diabetes, is a disease characterised by

high blood sugar

(

blood glucose

) levels. Normally, these levels are controlled by

insulin

, a hormone produced by the pancreas. Insulin lowers the blood sugar level. When the blood glucose rises (e.g. after eating), insulin is released from the pancreas to normalise the glucose level. With diabetes, the absence or insufficient production of insulin causes

hyperglycaemia

(raised blood glucose levels). This can result in several problems, including: blurred vision, excessive thirst, fatigue; nausea; frequent urination, weight loss despite an increase in appetite; bladder, skin and vaginal infections. There are three main types of diabetes:

Type 1 Diabetes

is usually diagnosed early in life. With this type, little or no insulin is made, so daily injections of insulin are needed. The exact cause is unknown, but genetics, viruses and autoimmune problems may play a role. Patients with type 1 diabetes usually develop symptoms over a short period of time.

Type 2 Diabetes

is the most common form of diabetes and usually occurs in adulthood. For many people (but not all) it can be prevented through living a healthy lifestyle.

Gestational Diabetes

develops during pregnancy in a woman who does not have diabetes. Various blood tests are used to diagnose diabetes. Although diabetes is a chronic (lifelong) condition, it can be controlled. Long-term aims are to reduce symptoms and prevent diabetes-related complications such as blindness, heart disease, kidney failure and amputation of limbs. These goals are accomplished through: blood pressure and cholesterol control; medication or insulin use; self-testing of blood glucose levels; exercise; foot care; meal planning and weight control; education and support.