Self-controlled children stay leaner in the transition to adolescence

In a prospective longitudinal study, we examined whether the personality trait of self-control protects against weight gain during the transition from childhood to adolescence. We obtained multi-method, multi-source measures of self-control from a socioeconomically and ethnically diverse sample of 105 fifth-grade students. Height and weight were recorded by the school nurse and used to calculate age- and gender-specific standardized body mass index (BMI) z-scores. Self-controlled fifth graders had lower BMI z-scores in eighth grade compared to their more impulsive peers, and this relationship remained significant when controlling for potential confounds, including gender, age, socioeconomic status, ethnicity, IQ, and happiness. Moreover, when controlling for the same covariates, self-control measured in fifth grade predicted decreases in BMI z-scores from fifth to eighth grade. These results suggest that more self-controlled children are protected from weight gain in the transition to adolescence.