The association between short sleep duration and body mass index among South Korean children and adolescents.

This study aims to examine the relationship between sleep duration and body mass index (BMI) in two South Korean samples: children and adolescents. Nationally representative secondary data (i.e., the Korean Survey on the Obesity of Youth and Children) collected in 2009 were analyzed (N = 2,499 for children and N = 7,431 for adolescents). Descriptive statistics and analysis of variance were implemented to examine BMI levels depending on sleep duration. Multiple regression analysis was conducted to explore the existence of a strong association between sleep duration and BMI z score after controlling for other factors. In both samples, sleep length had a reverse linear relationship with BMI z score, and shorter sleep duration was significantly associated with an increase in BMI z score. School nurses should take note of the strong association between sleep duration and BMI for more effective weight control in children and adolescence.