Sleep Duration, Sleep Regularity, Body Weight, and Metabolic Homeostasis in School-aged Children. Objective: The goal was to explore the effects of duration and regularity of sleep schedules on BMI and the impact on metabolic regulation in children. Methods: Sleep patterns of 308 community-recruited children 4 to 10 years of age were assessed with wrist actigraphs for 1 week in a cross-sectional study, along with BMI assessment. Fasting morning plasma levels of glucose, insulin, lipids, and high-sensitivity C-reactive protein also were measured for a subsample. Results: Children slept 8 hours per night, on average, regardless of their weight categorization. A nonlinear trend between sleep and weight emerged. For obese children, sleep duration was shorter and showed more variability on weekends, compared with school days. For overweight children, a mixed sleep pattern emerged. The presence of high variance in sleep duration or short sleep duration was more likely associated w...