Sleeping on a schedule that is out of whack with your body’s natural rhythms has long been linked to obesity and type 2 diabetes. Now a new study that subjected participants to three weeks of disrupted, short sleep sessions has begun to tease out just how those problems may arise. Researchers at Brigham and Women’s Hospital carefully monitored 21 healthy people who lived in a laboratory where their sleep schedules were tweaked, from normal night-time sleeping to five-and-a-half-hour spurts of sleep, spread out at all times of day and night.