Childhood overweight and parent- and teacher-reported behavior problems: evidence from a prospective study of kindergartners.

OBJECTIVES: To determine if there is a relationship between overweight and behavior problems among children as young as 5 years old by studying the association between overweight and behavioral health at entry into kindergarten and to determine whether overweight status is a risk factor for the onset of new behavior problems during the first 2 years in school.

DESIGN: We use data from a nationally representative sample of kindergartners in the United States-the Early Childhood Longitudinal Study-Kindergarten class. Data on height, weight, and parent- and teacher-reported behavior problems were collected 3 times during their first 2 years in school for 9949 children. We use a multivariate regression analysis that controls for sociodemographic characteristics, parent-child interaction, birth weight, and mother's mental health.

RESULTS: Among girls, but not boys, there is a significant association between overweight and teacher-reported externalizing behavior problems (odds ratio [OR], 1.81; 95% confidence interval [CI], 1.23-2.68), teacher-reported internalizing behavior problems (OR, 1.54; 95% CI, 1.09-2.17), and parent-reported internalizing behavior problems (OR, 1.49; 95% CI, 1.08-2.06) at the beginning of kindergarten. However, overweight status was not a risk factor for the onset of new behavior problems over time for either girls (teacher-reported externalizing behavior problems: OR, 0.58 [95% CI, 0.25-1.33]; teacher-reported internalizing behavior problems: OR, 1.34 [95% CI, 0.88-2.03]; and parent-reported internalizing behavior problems: OR, 1.29 [95% CI, 0.82-2.01]) or boys (teacher-reported externalizing behavior problems: OR, 1.02 [95% CI, 0.67-1.57]; teacher-reported internalizing behavior problems: OR, 1.02 [95% CI, 0.68-1.52]; and parent-reported internalizing behavior problems: OR, 1.42 [95% CI, 0.94-2.15]), whereas low family income and maternal depression were strong predictors of such problems.

CONCLUSIONS: Childhood overweight is already associated with behavior problems when girls start school, but not boys. In contrast to common belief, overweight status does not predict the onset of new internalizing or externalizing behavior problems during the first 2 years of school.