What happens when you rouse people hundreds of time a night when they go into deep sleep — besides the possibility that they might get seriously grumpy?

Their bodies behave as if they are on an express train to diabetes. After just three nights of disturbed sleep, researchers have found, otherwise healthy young volunteers had trouble regulating their blood sugar. It was almost as if they had gained 20 to 30 pounds, said the study, which appears online in The Proceedings of the National Academy of Sciences. The lead author is Dr Esra F Tasali of the University of Chicago. For the study, nine volunteers spent two or three nights at a sleep lab on two visits. On the shorter visit, they were allowed to sleep undisturbed. On the longer, whenever they went into slow-wave sleep, they heard sounds loud enough to interrupt the sleep stage but not wake them. Afterward, the volunteers were found to be less sensitive to the insulin the body produces to regulate sugar levels. And they did not produce more insulin to make up for it. People with weight problems often do not sleep well, the researchers said. The same is true for many people as they age. The findings suggest that if sleep can be improved, perhaps the risk of diabetes may be lowered.

New York Times