Men who don't get the right amount of sleep may have an increased risk of developing diabetes, a recent study suggests.
Plenty of previous research has linked sleep problems to diabetes, but the reasons behind this connection still aren't well understood, said lead study author Femke Rutters of Vrije University Medical Center in Amsterdam.
The current study looked at one possible explanation: insulin resistance.
Researchers examined data on sleep patterns and insulin resistance for 788 men and women who didn't have diabetes. People with obesity, heart disease, high blood pressure or elevated cholesterol levels were excluded from the analysis.
To measure sleep, researchers asked participants to wear accelerometers during most waking hours. Periods when people took these motion detectors off for longer than an hour were counted as sleep.
Overall, people slept an average of 7.3 hours a night, the study team reports in the Journal of Clinical Endocrinology and Metabolism, online June 29.
Men who slept much more or less than average were more likely to have insulin resistance than their peers who got average amounts of rest, the study found.
For women, however, the opposite happened. Women had less insulin resistance when they got more or less sleep than average.
It's unclear from the study findings why this gender gap occurred, Rutters said by email.
The results for women contradict results from numerous previous studies, noted Dr. James Gangwisch, a researcher at Columbia University in New York who wasn't involved in the study.
One shortcoming of the study is that it didn't examine what people ate, Gangwisch said by email.
"Getting adequate sleep can help with insulin sensitivity and appetite," Gangwisch said. "Getting enough sleep can also help provide the energy necessary to exercise regularly."
Another limitation of the study is the way sleep was measured, noted Kristen Knutson, a researcher at the University of Chicago who wasn't involved in the study.
Counting all the hours people didn't wear accelerometers as sleeping time might not be accurate because it wouldn't capture times when people were awake during the night, or sleeping fitfully, Knutson said by email.
Even so, the study adds to a growing body of evidence suggesting that insufficient sleep may be one trigger for developing diabetes, Knutson said.
"Quite a large number of studies have shown short sleep duration to be associated with diabetes," Rutters noted.
"The take-home message is that even when you are healthy, sleeping too much or too little can have detrimental effects on your health," Rutters added.
Most adults typically need about seven or eight hours of sleep a night, according to the U.S. Centers for Disease Control and Prevention. In addition to boosting the risk of diabetes, insufficient sleep is also associated with other chronic health problems like obesity, depression and cardiovascular disease.