March 14, 2012 -- Being sleep deprived may make you eat more than usual, according to a new study.
When researchers compared people allowed to sleep as much as they wished with those who slept just two-thirds of their normal time, they found that sleep deprivation was linked to eating more calories.
"When people were sleep deprived, they ate an extra 549 calories per day," says researcher Andrew Calvin, MD, MPH, a fellow in cardiovascular disease and assistant professor of medicine at Mayo Clinic, Rochester.
Over a week's time, that could add up to a pound of weight gain. However, Calvin says, "we don't know how long this effect lasts." His study lasted eight days.
He will present the findings today at the American Heart Association's Epidemiology and Prevention/Nutrition, Physical Activity, and Metabolism 2012 Scientific Sessions in San Diego.
The research echoes previous studies finding that lack of sleep is linked with weight gain and obesity, both in adults and children.
The study was funded by the National Institutes of Health, the Minnesota Obesity Center, and the Mayo Clinic.
Sleep Deprivation Effects: Study Details
Calvin and his team studied 17 men and women, ages 18 to 40. First, they ruled out sleep disorders by having participants spend a night in a sleep lab.
Next, the participants wore a wristwatch-sized device called an actigraph to track their sleep for three nights at home. The researchers evaluated how much time each person normally slept.
Next was the eight-day study in the sleep lab. Men and women were randomly assigned to sleep as much as they wanted or to sleep only two-thirds of their normal sleep time.
During the at-home phase, the average amount of sleep was 6.5 hours.
During the sleep lab phase, the sleep-deprived group averaged 5.2 hours a night. The other group continued to sleep about 6.5 hours nightly.
The National Sleep Foundation suggests adults get seven to nine hours of sleep a night.
Everyone had access to as much food as they wanted. Food intake was logged.