What exactly is type 2 diabetes?

Type 2 diabetes is the fastest-growing health epidemic of our times, and the number of people in the UK with the condition is predicted to rise to five million by 2025. It develops when the level of glucose (an essential sugar used for energy in the body) in the bloodstream is higher than normal.

It usually occurs from middle age but, alarmingly, the under-40s now account for 12 per cent of all newly diagnosed cases.

In the short term, abnormally high blood sugar causes – among many things – tiredness, extreme thirst (and, subsequently, needing the loo all the time), and blurred vision.

Long-term, type 2 diabetes can lead to serious health complications including damage to the retina, kidneys and nerves, and a higher risk of heart attack, stroke and amputation.

When we eat carbohydrates (sugars and starch), they are broken down into glucose by the body, which is then absorbed from the gut into the bloodstream and transported to the tissues to be used as energy. The latter part of this process is controlled by insulin – a hormone produced by the pancreas.

The main problem in type 2 diabetes is that accumulation of fat in the internal organs (particularly the liver) means that insulin doesn’t work properly and glucose builds up in the bloodstream. The pancreas produces more insulin in an attempt to control this but eventually the body becomes more resistant to insulin and so blood-glucose levels rise regardless.

If you have been diagnosed with type 2 diabetes, that will be because your blood sugar has been found by blood tests to be consistently higher than it should be both when you’ve not eaten, and after a meal.