Diabetes (full name diabetes mellitus) is due to a failure of the body to produce enough of a hormone called insulin and/or the body becoming resistant to the action of insulin.
Insulin is produced by the pancreas, a large gland tucked away deep in the abdomen, under the stomach. Insulin helps control blood glucose (sugar) levels by promoting the uptake of glucose into the body's cells for use as an energy source or for storage.
Diabetes is a chronic (long-term) illness affecting many parts of the body. It has a particularly bad effect on blood vessels, with a build-up of cholesterol and other deposits causing blood vessels to narrow, block and leak. This results in reduced blood supply to many tissues and makes diabetes a major cause of blindness and kidney failure as well as contributing to many other problems such as heart disease, strokes and poor circulation to the legs which may cause gangrene.
Nerves may also be damaged, as in diabetic neuropathy, which may lead to numb hands and feet. This can be a major problem when the feet are affected as they are easily damaged with minor injuries which may not be noticed due to reduced sensation. These injuries can also be slow to heal because of poor circulation. For this reason, foot care is vital for people with diabetes. They must be sure to wear well-fitting shoes, avoid tight socks and not go barefoot. A regular visit to a podiatrist can help prevent problems.
Diabetes may be suspected if any of the following symptoms occur:
Diabetes is diagnosed by testing the blood and finding abnormally high levels of glucose, and may involve a glucose tolerance test in which you drink a sugary liquid and then have your blood glucose level measured.
Most people with diabetes have what is called type 2 (or non-insulin dependent) diabetes. This usually occurs after the age of 40 in people who are overweight and have diabetes in the family, although it is occurring increasingly in younger people. Type 2 diabetes can often be managed through careful attention to diet and increasing exercise. Sometimes tablets called oral hypoglycaemics are needed and, occasionally, insulin injections.
About 10 to 15 per cent of people with diabetes have the more serious type 1, or insulin dependent, diabetes. This affects younger people, often beginning in early childhood, and requires life-long treatment with injections of insulin. As well as needing these injections at least once a day, strict attention to diet and activity levels is vitally important.
Treatment is aimed at keeping the blood glucose levels as close to normal as possible. This means regular testing, which can be done at home. The required dose of insulin can then be adjusted, depending on the blood glucose level.
Although there is no cure for diabetes, modern treatment means that the outlook for people with diabetes is good and complications of the illness can usually be kept to a minimum and their onset delayed if blood glucose levels are kept as close to normal as possible.
Last Reviewed: 26 May 2003