Research has found that people burn fewer calories when they sleep during the day and log their waking hours after the sun’s gone down. To come to this finding, University of Colorado at Boulder researchers studied 14 healthy adults for six days. For two days, study participants slept at night and stayed awake during the day, then they reversed their routines to mimic the schedules of night owls. When participants slept during the day, researchers found that they burned 52 to 59 fewer calories than they did while catching their zzz’s in the evening—likely because the schedule messed with their circadian rhythm, the body's internal clock that plays a major role in metabolism function. If you have no choice but to sleep during the day, aim to cut 50-60 calories from your daily diet.
