Abstract
BACKGROUND: Effortful control, or the regulation of thoughts and behaviour, is a potential target for preventing childhood obesity. OBJECTIVES: To assess effortful control in infancy through late childhood as a predictor of repeated measures of body mass index (BMI) from infancy through adolescence, and to examine whether sex moderates the associations. METHODS: Maternal report of offspring effortful control and measurements of child BMI were obtained at 7 and 8 time points respectively from 191 gestational parent/child dyads from infancy through adolescence. General linear mixed models were used. RESULTS: Effortful control at 6 months predicted BMI trajectories from infancy through adolescence, F(5,338) = 2.75, p = 0.03. Further, when effortful control at other timepoints were included in the model, they added no additional explanatory value. Sex moderated the association between 6-month effortful control and BMI, F(4, 338) = 2.59, p = 0.03, with poorer infant effortful control predicting higher BMI in early childhood for girls, and more rapid increases in BMI in early adolescence for boys. CONCLUSIONS: Effortful control in infancy was associated with BMI over time. Specifically, poor effortful control during infancy was associated with higher BMI in childhood and adolescence. These findings support the argument that infancy may be a sensitive window for the development of later obesity.