LAUSR

A substantial body of epidemiologic data has demonstrated associations between obesity and shorter sleep duration.1–6 These associations have been found in both adults and children and in diverse populations. These findings are particularly relevant because insufficient sleep is a widespread problem in the United States.7,8 Depending on the cutoff used to define inadequate sleep duration, anywhere from 30% to 90% of American children sleep fewer than the recommended number of hours per night.7,8 Adolescents meet recommended targets for sleep duration less frequently than younger children.7–9 The pressure of homework or extracurricular activities, the distraction of electronics, the mismatch between adolescents’ biological clocks and school schedules, and the noisy environments of many inner cities may be contributing factors for the relative sleeplessness of these children and adolescents. To date, most pediatric studies investigating relationships between sleep and obesity have been strictly observational and therefore do not provide information to make inferences about causation. Decreased sleep duration of children aged 16 months to 17 years is associated with a risk ratio between 1.86 and 2.06 for obesity, as well as increased calorie and sugar intake in many10–13 but not all studies.14 … Address correspondence to Nicole Glaser, MD, Department of Pediatrics, Section of Endocrinology, University of California Davis, School of Medicine, 2516 Stockton Blvd, Sacramento, CA 95817. E-mail: nsglaser{at}ucdavis.edu