Last week doctors gathered in Rome for a conference of the European Association of the Study of Diabetes. They were there to discuss the latest treatment of diabetes type 2, arguably the greatest long-term problem facing 21st-century medicine. The ever-increasing number of patients developing the condition in part reflects the rise in obesity and lack of exercise, as well as a genetic tendency to the condition.

One patient in five develop kidney failure and there's a 50 per cent chance of death from cardiovascular disease, usually a stroke or a coronary heart attack. Diabetes is also responsible for blindness in 2 per cent of sufferers and severe loss of vision in 10 per cent. Half of patients develop nerve damage, the most common manifestations of which are pain, tingling and numbness in feet and hands, and impotence in men.

While the Rome conference was taking place, it emerged that President Kim Jong Il of North Korea had failed to attend his country's annual military rally. As it has been widely reported that Mr Kim suffers from diabetes type 2, speculation was rife that he might well have suffered a stroke or heart attack, common complications.

Although effective anti-diabetic treatment has been available for only around 80 years, the disease has been recognised for several millennia. The Ancient Egyptians recorded cases 3,500 years ago and there are even earlier Chinese reports of it. The full name is diabetes mellitus - from the Latin mellitum, a preparation made with honey. Roman physicians diagnosed diabetes by tasting a finger dipped in the patient's urine. If the lick revealed a sweet, honey-like taste, the doctor knew it was diabetes.

In 1921 Banting and Best isolated insulin, the hormone produced by the beta cells of the pancreas that controls blood sugar levels. However, only recently has the complex physiological and biochemical mechanism that regulates blood sugar levels been understood.

Other hormones, as well as those from the pancreas, help to maintain blood sugar levels. The pancreas reacts to the level of circulating blood sugar by producing varying amounts of insulin, the hormone that encourages the body's cells to pick up glucose from the blood stream and use it to produce energy. If the level is too low, glucagon is produced and this restricts the production of insulin. Among the other hormones produced to maintain a balanced blood sugar level are incretins, formed in the gastro-intestinal tract in response to a meal. The incretins are the glucagon-like peptide GLP-1 and the gastric inhibitory peptide GLP that act through the beta cells of the pancreas.

A greater understanding of the body's method of regulating carbohydrate and hence blood sugar levels, whether from the porridge and muesli of the health-conscious eater or the chocolates and biscuits of the comfort-eater, has enabled the development of liraglutide, a new drug designed to improve blood sugar control. It can also increase weight loss, reduce blood pressure and have a beneficial effect on the beta cells.

As well as insulin injections for type 1 diabetes and some cases of type 2, tablets that lower blood sugar have been available for many years. These include sulphonylureas and the biguanides - this latter group includes Glucophage (metformin). Other oral drugs, such as pioglitazone or rosiglitazone, stimulate the release of insulin from the beta cells. But, unlike insulin or liraglutide, they don't seem to have the same beneficial effect on the condition of the beta cells.

The Rome conference was given details of a phase 3 clinical study of liraglutide, manufactured by Novo Nordisk. The international trial involved 4,000 people suffering from diabetes type 2. Once liraglutide has been approved it will be used as an addition to metformin. This can be enhanced by adding a glitazone. Liraglutide increases the quantity and the quality of a patient's remaining beta cells, increases insulin sensitivity and decreases glucagon production.

It also has the advantage of reducing the appetite so that people won't be so tempted to visit the biscuit tin and will keep their weight down.

Now that doctors have worked so hard to unlock the secrets of our bodies and develop a better understanding of the complexity of the body's engineering, they will be able to help those with diabetes to live longer.