How Lack of Sleep Can Affect Glucose MetabolismWednesday, October 21, 2009
Regular readers of these pages will recall several posts on the importance of adequate restorative sleep for the maintenance of healthy weights. As blogged previously, reduced sleep is not only associated with increased risk for obesity, but sleep deprivation also has profound effects on ingestive behaviour.
A new study by Schmid and colleagues from the University of Luebeck, Germany, published in the Journal of Clinical Endocrinology and Metabolism now shows that sleep deprivation can have profound effects on glucagon levels, a key determinant of glucose control.
Their study examined the effects of a single night of sleep restriction to 4.5 hours vs. a night of 7 hours of sleep in a crossover study in 10 healthy men.
Sleep deprivation not only reduced basal plasma glucagon levels but also glucagon response to a hypoglycemic clamp, but had no effect on circulating concentrations of insulin, C-peptide, epinephrine, norepinephrine, or growth hormone. Basal concentrations of ACTH and cortisol were also reduced after sleep loss during baseline.
This finding provides further evidence for the notion that glucose homeostasis is sensitive to subtle changes in sleep duration.
Importantly, as glucagon is a key hormone that helps maintain normal glucose levels during fasting by inducing the liver to convert stored glycogen into glucose and release it into the bloodstream, lack of glucagon release resulting from sleep deprivation could promote eating in response to hypoglycemia, thereby promoting weight gain. This may be of particular relevance to diabetic patients on hypoglycemic medications, who are particularly prone to hypoglycemic episodes.
This interesting observation clearly supports the notion that ensuring adequate amounts of sleep should be an important cornerstone of weight management.