The diabetes explosion

Millions of people are at risk from diabetes and we need to examine our lifestyles and those of our children to prevent it becoming an epidemic, says Dr Lesley Hickin.

In the UK, 1.4 million people suffer from diabetes and at least another million are estimated to have it without knowing. The cost of treating diabetes and related conditions is soaring and is set to use up a fifth of the entire NHS budget by the year 2010.

The reasons for the increase include an ageing population (Type 2 diabetes is more common among older people), growing obesity among all age groups and lack of exercise. There are also worrying signs that overweight children who don't exercise are risking diabetes in later life. Three out of five adults in the UK are considered overweight or obese, and one in four children.

What is diabetes?
Diseases involving the chemical reactions going on in your body are called metabolic disorders. Diabetes (or diabetes mellitus, sugar diabetes) is the most common of these. Normally carbohydrate-containing foods are broken down into glucose (sugar) to be absorbed from the bowel into the bloodstream. Glucose in the blood is then delivered to cells in all the tissues of the body, where it is broken down to give us energy by chemical reactions.

Insulin, a hormone produced by a gland called the pancreas, situated behind the stomach, helps glucose enter cells. Levels are increased in response to a rise in the blood glucose level, and levels of insulin go down when blood glucose levels fall, for example during exercise. In this way the blood glucose level is kept within a narrow range. Insulin also enables carbohydrate stored in muscles and the liver to be converted to glucose when necessary.

In diabetes the amount of glucose in the body rises too high because of insufficient insulin or resistance to the action of insulin in the tissues. The cells have to find an alternative source of energy, particularly stored fat, leading to a build-up of toxic waste products in the body. Glucose accumulates in the blood and spills out into the urine, drawing extra water with it. All these processes can lead to the symptoms of diabetes detailed below.

Many people think of diabetes simply as a disorder of glucose and insulin, but it would be more realistic to think of it as a complicated metabolic disorder of glucose and blood lipids (fats in the blood including cholesterol), high blood pressure and disease of blood vessels.