What is 'diabetes'?
'Diabetes' is the abbreviated term for a condition known as 'diabetes mellitus'. There are two main forms of diabetes in the general population, type 1 and type 2. A third type, known as 'gestational diabetes' is associated with pregnancy. All forms of diabetes involve a reduced ability of the body to handle blood glucose (the type of sugar transported in the blood).
In normal health, blood glucose is maintained at a fairly constant level, although it does fluctuate slightly. Blood glucose level is controlled largely by the action of insulin, a hormone produced in the pancreas. Insulin stimulates the uptake of glucose, amino acids and fat (in the form of triglycerides) from the blood into the tissues for use. Insulin also promotes the storage of blood glucose in the liver and muscles. Thus insulin prevents the glucose level becoming too high in the blood. If insulin production is too low, or the insulin does not have its usual effect, blood glucose can climb to dangerous levels (a condition known as 'hyperglycaemia'). When blood glucose levels are high over long periods of time, damage to cells within the body can result. For example, nerve and vascular damage are common.
Type 1 diabetes, previously known as 'juvenile-onset' or 'insulin-dependent diabetes mellitus' (IDDM), involves destruction of the cells of the pancreas that produce insulin, so people with type 1 diabetes have a deficiency of insulin. As a result, injections of insulin are required.
Type 2 diabetes, previously known as 'adult-onset' or 'non-insulin-dependent diabetes mellitus' (NIDDM), does not usually involve a deficiency of insulin production (at least not in the initial stages), rather, the body becomes resistant' to the effects of insulin. While type 2 diabetes is at this early stage, lifestyle changes (discussed in detail below) such as diet and exercise diet may be enough to control blood sugar levels with no (or minimal) need for medication. However, type 2 diabetes may progress to the stage where regular medication is also needed. In some cases, as diabetes progresses, a combination of treatments may be required. This could mean an altered diet, lifestyle changes, regular medication and insulin injections may all be necessary.
Gestational diabetes is usually only a temporary condition, affecting about 3% of pregnant women. Individuals who experience gestational diabetes have greater risk of developing type 2 diabetes in the future.
Because the vast majority (more than 90%) of people with diabetes have type 2, and its incidence is growing in epidemic proportions, this FAQ will address mainly type 2 diabetes. For more information on type 1 and gestational diabetes, see 'Suggested Additional Reading' at the end of this FAQ.
How does having type 2 diabetes affect someone's health?
Diabetes, unless treated appropriately, greatly increases the risk of a range of diseases, including heart disease, blindness, gangrene (leading to the need for limb amputations) and kidney disease. It is estimated that the risk of having a heart attack among people with type 2 diabetes is equal to that of someone without diabetes who has already experienced a heart attack.
But diabetes greatly increases these risks only if it is not treated
effectively. With proper management, including appropriate alterations to diet and lifestyle as described below, the vast majority of people with diabetes can lead full and satisfying lives.