Trying to get rid of that extra fat? Sleep in.
It may sound counterintuitive, but a study that randomly assigned dieters to different sleep regimens found that participants allowed only five and a half hours in bed at night lost less flab than those who spent eight and a half hours in bed and got more sleep, reports the New York Times.
The total amount of weight loss did not differ — both groups lost about six and a half pounds over two weeks — but the optimal outcome of a diet is to lose fat, not muscle, researchers said.
The sleep-deprived participants felt hungrier than the others, and had higher levels of ghrelin, a hormone that drives appetite, the study found.
“The bottom line is that if people are trying to diet and lose weight for health reasons, it makes sense to get a sufficient amount of sleep,” said Dr. Plamen D. Penev, an assistant professor of medicine at the University of Chicago and the senior author of the study, which was released Tuesday in Annals of Internal Medicine. “If they’re not getting enough sleep as they diet, they may have higher levels of hunger and be struggling to adhere to the regimen.”
The study was small, including only 10 adults; they lived in a clinical research center for weeks at a time so their exercise, food intake and sleep schedules could be tightly controlled and monitored.