Suppression of slow-wave sleep in healthy young adults significantly decreases their ability to regulate blood-sugar levels and increases the risk of type 2 diabetes, report researchers at the University of Chicago Medical Center in the Early Edition of the Proceedings of the National Academy of Science, available online as soon as Dec. 31, 2007.
Deep sleep, also called slow-wave sleep, is thought to be the most restorative sleep stage, but its significance for physical well-being has not been demonstrated. This study found that after only three nights of selective slow-wave sleep suppression, young healthy subjects became less sensitive to insulin. Although they needed more insulin to dispose of the same amount of glucose, their insulin secretion did not increase to compensate for the reduced sensitivity, resulting in reduced tolerance to glucose and increased risk for type 2 diabetes. The decrease in insulin sensitivity was comparable to that caused by gaining 20 to 30 pounds.
Previous studies have demonstrated that reduced sleep quantity can impair glucose metabolism and appetite regulation resulting in increased risk of obesity and diabetes. This current study provides the first evidence linking poor sleep quality to increased diabetes risk.
"These findings demonstrate a clear role for slow-wave sleep in maintaining normal glucose control," said the study's lead author, Esra Tasali, MD, assistant professor of medicine at the University of Chicago Medical Center. "A profound decrease in slow-wave sleep had an immediate and significant adverse effect on insulin sensitivity and glucose tolerance."
Since reduced amounts of deep sleep are typical of aging and of common obesity-related sleep disorders, such as obstructive sleep apnea these results suggest that strategies to improve sleep quality, as well as quantity, may help to prevent or delay the onset of type 2 diabetes in populations at risk, said Eve Van Cauter, PhD, p
|Contact: John Easton|
University of Chicago Medical Center