“Late Gain” — The Discovery Files

Teenagers and adults who go to bed late on weeknights are more likely to gain weight than their peers who hit the hay earlier, according to a new study from UC Berkeley that has found a correlation between sleep and body mass index. Berkeley researchers analyzed longitudinal data from a nationally representative cohort of more than 3300 youths and adults, and found that over time for every hour they went to bed after 11:15 p.m., they gained 2.1 points on the BMI index. This gain occurred roughly over a five-year period.