Current estimates predict that by 2010 some 220 million people will have succumbed to diabetes, which basically is a failure of the body to regulate blood sugar. Although it need not be debilitating, poorly controlled diabetes can lead to complications such as blindness, strokes, heart disease and lower limb amputations. And for every person diagnosed, there's at least another unaware he or she has it.

``A lot of diabetes is hidden,'' says Professor Stephen Bloom, chair of the British Diabetic Association's research committee. ``Many people die of heart disease, while the underlying factor is probably undiagnosed diabetes.'' In most developed countries, it is the fourth or fifth leading cause of death.

Normally the amount of glucose in the blood stream is controlled by insulin produced by the pancreas. In diabetes, this control mechanism is disrupted. By far the most common type is Type II, or non-insulin dependent diabetes mellitus (NIDDM), which usually afflicts the over-40s and causes the majority of diabetes-related deaths. But it is almost entirely preventable, says Bloom.

``Type II is caused principally by obesity. The beta cells in the pancreas which produce insulin become exhausted with the effort of overcoming the excess weight, and begin to die off. If you eat less and exercise more, you won't get it.'' But that can be easier said than done. ``I have a fair amount of willpower and I know overweight people have a 50 times higher incidence of diabetes, but I still find it difficult to control what I eat,'' says Bloom, who is looking into ways of regulating appetite.

The good news is that diabetes research is constantly breaking new ground. In the US, the new drug troglitazone, marketed as Rezulin, is helping people with Type II diabetes who do not respond well to conventional diet and drug treatments. It re-sensitises the body to insulin and so helps supplies go further - in one study, patients taking it for six months were able to reduce their insulin dose by 58 per cent.

In the UK, however, troglitazone has been withdrawn following concerns about side effects, although so far these have proved minimal, says Bloom, who believes it represents a new line of drugs that will be powerful in 10 years' time.

Other research is focusing on oral forms of insulin to replace injections. An initial UK study on a preparation called macrulin indicates it may be effective in lowering blood sugar in Type II diabetics but Bloom says: ``While oral insulin is perfectly possible in theory, in practice it is difficult to get precise doses. A child needing 32 units of injected insulin can have a severe attack of low blood sugar at 34 units - you're working with a very narrow range. By mouth the absorption rate would be much more variable; if anxious you'd absorb more and with diarrhoea you'd absorb less.'' There is hope on the horizon for those at risk of the other, currently unpreventable, form of diabetes - Type I, or insulin-dependent diabetes mellitus (IDDM). Most common in childhood and adolescence, it results from the body mounting an autoimmune attack on its own insulin-producing beta cells in the pancreas.

``Although we don't yet know what triggers the autoimmune attack, we may be able to pick it up through screening and use drugs to stop it in its tracks,'' says Bloom, ``Attacking itself is a pretty daft thing for the body to do - if you could only damp don the process, you might just get the body to see reason.''