Association between overweight/obesity and academic performance in South Korean adolescents.

The purpose of this study was to examine the relationship between academic performance and obesity/overweight among South Korean adolescents. Our data set included 72,399 adolescents in grades 7-12 who had participated in the 5th Korea Youth Risk Behaviour Web-based Survey (KYRBWS-V) in 2009. We assessed the association between academic performance and body mass index (BMI), using multivariate logistic regression analysis after adjusting for covariates such as age, parents' education level, economic status, mental stress experienced, sleep duration, frequency of muscle-strengthening exercises, smoking and drinking behaviour, and vigorous and moderate physical activity (PA). For boys, being overweight (compared with being of normal weight) had a significantly greater odds of poor academic performance (OR=1.182, 95% Cl 1.052-1.329, p=0.005). Obese boys had 1.182 (1.048-1.332, p=0.006), 1.461 (1.294-1.648, p<0.001), and 1.443(1.256-1.657, p<0.001) greater odds of having average, poor, and very poor performance, respectively. In the analysis for girls, overweight girls had 1.314 (1.124-1.536, p<0.001) and 1.296 (1.084-1.548, p=0.004) greater odds of having poor and very poor academic performance, respectively. Finally, obese girls had 1.374 (1.098-1.718, p=0.005), 1.672 (1.339-2.089, p<0.001), and 1.887 (1.478-2.409, p<0.001) greater odds of having average, poor, or very poor academic performance, respectively. Thus, overweight/obesity was negatively associated with academic performance in both boys and girls. The results of this study indicate that adolescents would benefit from weight management to prevent obesity and, possibly, improve academic performance.