If you are healthy and go to bed late regularly and you do not sleep enough, your risk of gaining weight is significantly greater than if you go to bed earlier and have a good night's sleep every night, says a new study published in the journal Sleep.If you also eat late at night, you will probably put on even more weight, researchers from the University of Pennsylvania added. In fact, they say it is the extra eating among sleep-deprived individuals that appears to be the main reason for the weight gain.
The authors say that theirs is the largest study so far of healthy people, under controlled laboratory conditions, that demonstrates a clear association between very late night sleeping combined with sleep restriction and weight gain.Andrea Spaeth and team had one group of participants sleeping just from 4 a.m. to 8 a.m. each night for five nights running, and compared them to a control group who were in bed from 10 p.m. to 8 a.m.The investigators also found that those who slept much less consumed more food, and therefore calories, compared to the normal-hours sleepers. Meals eaten during the late-night hours had a higher overall fat content than the other meals.
Lead author, Andrea Spaeth, a doctoral candidate in the psychology department at the University of Pennsylvania, said:
"Although previous epidemiological studies have suggested an association between short sleep duration and weight gain/obesity, we were surprised to observe significant weight gain during an in-laboratory study."
Medical News Today