Successive nights of disturbed sleep appear to put people at greater risk of developing type 2 diabetes, according to research in which scientists interfered with volunteers' sleep patterns.

The research is the first to show that disturbed sleep can affect the production of insulin, and consequently a person's ability to metabolise glucose. It could have huge implications for understanding and tackling the diabetes epidemic that is predicted to grip Western countries due to increasingly obese populations.

According to the leading charity Diabetes UK, there are more than 2.3 million people with diabetes in the UK, and up to 750,000 more who have the condition but do not know it.

Between 85% and 95% of diabetes cases are type 2, which typically develops later in life and is linked to obesity.

Eve Van Cauter, a professor at the University of Chicago, and colleagues studied five healthy men and four healthy women aged between 20 and 31. The volunteers received two consecutive nights of undisturbed sleep and three nights during which they were prevented from entering the most restorative stages three and four of slow-wave sleep - a time when you do not dream.

The team reported in Proceedings of the National Academy of Sciences that after three nights of disturbed sleep the volunteers were significantly glucose-intolerant: they had, on average, 23% more glucose in their blood. The results suggest obesity and a lack of quality sleep may interact to cause type 2 diabetes.