What is Type 2 diabetes?

With Type 2 diabetes, the illness and symptoms tend to develop gradually (over weeks or months). This is because in Type 2 diabetes you still make insulin (unlike Type 1 diabetes). However, you develop diabetes because:

you do not make enough insulin for your body's needs, OR
the cells in your body do not use insulin properly. This is called 'insulin resistance'. The cells in your body become resistant to normal levels of insulin. So, you need more insulin than you normally make to keep the blood glucose level down, OR
a combination of the above two reasons.

Type 2 diabetes used to be known as maturity onset, or Non-Insulin Dependent Diabetes. It develops mainly in people older than 40 (but sometimes occurs in younger people). In the UK about 3 in 100 people aged over 40, and about 10 in 100 people aged over 65, have Type 2 diabetes. It is more common in people who are overweight or obese. It also tends to run in families. It is also more common in South Asian and African-Caribbean people (often developing before the age of 40 in this group).

What is Type 1 diabetes?

In Type 1 diabetes the beta cells in the pancreas stop making insulin. The illness and symptoms develop quickly (over days or weeks) because the level of insulin in the bloodstream becomes very low. Type 1 diabetes used to be known as juvenile, early onset, or Insulin Dependent Diabetes. It usually first develops in children or in young adults. Type 1 diabetes is treated with insulin injections and diet.

The rest of this leaflet deals only with Type 2 diabetes.