A multi-institutional team of researchers conducted the first study to evaluate how the duration of nightly sleep early in the semester affects first year college students end-of-semester grade point average (GPA). Using Fitbit sleep trackers, they found that students on average sleep 6.5 hours a night, but negative outcomes accumulate when students received less than six hours of sleep a night. The results are available in the Feb. 13 issue of the Proceedings of the National Academy of Sciences.