* With diabetes, the amount of glucose (sugar) in the blood is too high because the body cannot use it properly.
* In Type 1 ('juvenile-onset'), the body does not produce the hormone insulin, which helps the glucose enter the cells, where it is used as fuel by the body. The insulin-producing cells (beta cells) have been destroyed by the body's immune system. Type 1 is usually first diagnosed in people under 40, and is treated with insulin injections.
* In Type 2 ('adult-onset), the body does not produce enough insulin, or the insulin it produces does not work properly. Type 2 is treated by diet and exercise alone, or with tablets and, sometimes, insulin.
Indications of Type 2 include drinking a lot more; urinating a lot more, especially at night; developing thrush (rare in under-fives), or genital itching; bed-wetting once they have already been dry at night; and blurred vision.
Who gets diabetes?
* Around 1.3 million people have been diagnosed. A further million people are thought to have diabetes without knowing.
* Type 1 diabetes affects about 15 per cent of sufferers and is rising in children, particularly the under-fives.
* Type 2 affects about 85 per cent of sufferers, rising across all age groups.
