Why sleepless nights are causing diabetes
Just one sleepless night can hamper our ability to use insulin to process sugar in the bloodstream, according to a study -- which might explain why diabetes is on the rise.
Researchers said it may be no coincidence that while sleep duration has shortened in western societies, there has also been an increase in cases of "insulin resistance" and adult-onset diabetes.
"Our findings show a short night of sleep has more profound effects on metabolic regulation than previously appreciated," said Esther Donga, the Dutch researcher who led the study.
Type 2 diabetes is caused by the body's inability to adequately use insulin, a hormone produced by the pancreas, to control glucose sugar produced from food.
Sugar levels rise and can damage the eyes, kidneys, nerves, heart and major arteries.
The disease, linked to poor diet and lack of exercise, is reaching epidemic levels. An estimated 180 million people now suffer from diabetes around the world.
Previous studies have found that several nights of poor sleep can result in impaired use of insulin, but Donga said this was the first study to examine the effects of only a single bad night's sleep.
The Dutch scientists examined nine healthy people -- once after a night of eight hours sleep and once after a night of just four hours. The findings showed that partial sleep restriction during a single night reduced some types of insulin sensitivity by 19 to 25pc.
"Our data indicate that insulin sensitivity is not fixed in healthy (people), but depends on the duration of sleep in the preceding night," Donga wrote in the study.
"In fact, it is tempting to speculate that the negative effects of multiple nights of shortened sleep on glucose tolerance can be reproduced, at least in part, by just one sleepless night."
A study by US scientists last year found that people who slept less than six hours a night were 4.5 times more likely to develop abnormal blood sugar readings.