Abstract
OBJECTIVE: To test the hypothesis that healthy weight status and adherence to American Academy of Pediatrics (AAP) guidelines for diet and physical activity would extend to greater executive function (EF) at age 24 months. STUDY DESIGN: Parents of 24-month-old children from the STRONG Kids 2 cohort study (n = 352) completed the Behavioral Rating Inventory of Executive Function for Preschoolers (BRIEF-P) and reported physical activities, diet, and screen time. Toddlers met AAP guidelines if they consumed at least 5 servings of fruits and vegetables, were physically active, refrained from sugar-sweetened beverages, and limited daily screen time to <60 minutes. Relationships between EF, 24-month weight status, and meeting AAP guidelines were tested independent of child sex, ethnicity, socioeconomic status, weight status at birth, and maternal pregnancy weight status. RESULTS: Weight-for-length z-score had no effect on EF. Toddlers meeting the screen time guideline had greater EF (β, -0.125; 95% CI, 0.234 to -0.008), inhibitory self-control (β, -0.142; 95% CI, -0.248 to -0.029), and emergent metacognition (β, -0.111; 95% CI, -0.221 to 0.002), indicated by lower BRIEF-P scores. Those with more minutes of screen time had poorer overall EF (β, 0.257; 95% CI, 0.118-0.384), inhibitory self-control (β, 0.231; 95% CI, 0.099-0.354), cognitive flexibility (β, 0.217; 95% CI, 0.082-0.342), and emergent metacognition (β, 0.257; 95% CI, 0.120-0.381). Daily physical activity was associated with greater emergent metacognition (β, -0.116; 95% CI, -0.225 to -0.005). CONCLUSIONS: Meeting AAP guidelines for physical activity and screen time was related to greater EF in a demographically homogenous sample of toddlers. Future randomized control trials and more diverse samples are needed to confirm the directionality of this relationship. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT03341858.