Doctors are fingering a lack of sleep as at least partially responsible for a growing number of physical and psychological ailments. Diabetes is one of those ailments.
In a new study, researchers show how a lack of sleep can encourage pre-diabetic conditions in otherwise healthy young men. Specifically, researchers found that a persistent lack of sleep promoted increased fatty acid levels in the blood. Heightened fatty acid levels disrupt fat metabolism and disrupts insulin's ability to properly regulate blood sugar -- thus, diabetes.
The levels of fatty acids normally fluctuate throughout the day, but generally follow a pattern of peaking in the evening and receding overnight. But the new study showed a recession of fatty acid levels was mitigated by sleepless nights.
Study participants who got just a little more than four hours of sleep for four consecutive nights had elevated blood levels of fatty acids from about 4 a.m. to 9 a.m. The heightened levels corresponded with an increase in insulin resistance, as measured by an intravenous glucose-tolerance test. The insulin resistance, a hallmark of pre-diabetes, lasted nearly five hours.
The research also pulled the curtain back on the mechanisms encouraging heightened fatty acid levels in the study participants' blood.
"Curtailed sleep produced marked changes in the secretion of growth hormone and levels of noradrenaline -- which can increase circulating fatty acids," lead study author Josiane Broussard, a former graduate student at the University of Chicago, explained in a press release.
"The result was a significant loss of the benefits of insulin," Broussard said. "This crucial hormone was less able to do its job. Insulin action in these healthy young men resembled what we typically see in early stages of diabetes."
Broussard, having earned her PhD since the research was conducted, now works as a researcher at the Cedars-Sinai Medical Center's Diabetes and Obesity Research Institute in Los Angeles.
The new study was published online this week in the journal Diabetologia.
Previous research has found insomnia to increase the risk of stroke. Sleeplessness has also been linked with systematic inflammation, unstable blood sugar, high blood pressure, and other cardiovascular problems. The National Sleep Foundation recently put out updated recommendations for nightly sleep totals, most notably increasing the amount of sleep advised for teens to eight to ten hours.