Study author Dr. Virend Somers, professor of medicine and cardiovascular disease at the Mayo Clinic, in Rochester, Minn., and colleagues studied 17 normal, healthy young men and women for eight nights -- with half of the participants sleeping normally and half sleeping only two-thirds their normal time. The study participants ate as much as they wanted during the study.
The study found in the group that was sleep deprived -- sleeping 1 hour, 20 minutes, less than the control group each day -- consumed an average 549 additional calories each day.
The amount of energy used for physical activity didn't significantly change between groups, suggesting neither those who slept less nor those who slept more burned additional calories.
The study found a lack of sleep was associated with changes in hormones related to eating -- increased leptin levels and decreased ghrelin -- changes that were more likely a consequence, rather than a cause, of overeating.
"Sleep deprivation is a growing problem, with 28 percent of adults now reporting that they get 6 or fewer hours of sleep per night," co-investigator Dr. Andrew D. Calvin said.
The findings were presented at the American Heart Association's Epidemiology and Prevention/Nutrition, Physical Activity and Metabolism scientific sessions in San Diego.