A small study supported past findings suggesting there is a link between sleep loss and diabetes.
According to the study, sleep loss can elevate levels of free fatty acids in the blood and lead to temporary pre-diabetic conditions in healthy young men, the University of Chicago Medical Center reported. The study was the first to look at the influence sleep loss had on 24-hour fatty acid levels and fat metabolism, which can reduce the ability of insulin to regulate blood sugars.
"At the population level, multiple studies have reported connections between restricted sleep, weight gain, and type 2 diabetes," said Esra Tasali, assistant professor of medicine at the University of Chicago and senior author of the study. "Experimental laboratory studies, like ours, help us unravel the mechanisms that may be responsible."
The researchers found that after three nights of getting only four hours of sleep, fatty acid levels in the blood (which usually peak and fall overnight), remained elevated from about 4 a.m. to 9 a.m. When these fatty acid levels were elevated the ability of insulin to regulate the blood sugar was reduced.
The study included 19 healthy male subjects between the ages of 18 and 30. The participants were monitored during periods of getting a full night's rest and of getting around four hours of sleep a night. The subjects' blood samples were collected at either 15 or 30 minute intervals for 24 hours, starting on the third of four nights of a given sleep pattern. A glucose tolerance test was also performed at the conclusion of the four day periods.
The study showed sleep restriction resulted in a 15 to 30 percent increase in late-night and early-morning fatty acid levels. The late-night rises in fatty acid levels were linked to an increase in insulin resistance that lasted for up to five hours.
"Curtailed sleep produced marked changes in the secretion of growth hormone and levels of noradrenaline-which can increase circulating fatty acids," said Josiane Broussard, a former graduate student at the University of Chicago who is now a post-doctoral research scientist at Cedars-Sinai Medical Center's Diabetes and Obesity Research Institute. "The result was a significant loss of the benefits of insulin. 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."
The findings suggest simple interventions, such as getting a good night's sleep, could be the key to fighting the current epidemics of diabetes and obesity.
The findings were published in a recent edition of the journal Diabetologia.
