Dietary-Related and Physical Activity-Related Predictors of Obesity in Children: A 2-Year Prospective Study

Background: This observational study examined cross-sectional and 24-month longitudinal associations of physical activity and dietary behaviors with change in BMI and percent body fat among children aged 6-9 years old. Methods: Data were from the control group (n = 271; 48% Latino) of a community-based childhood obesity prevention program. Assessments were conducted at baseline and at 24 months and included height and weight, bioelectrical impedance-derived percent body fat, and 10 physical activity and dietary behaviors measured via parent report of their child. Cross-sectional analysis of variances ANOVA) normal weight, overweight, obese) and longitudinal mixed-effects linear regression models were used to investigate the relation of each physical activity and dietary behavior with BMI and percent body fat. Results: At baseline, obese children engaged in less physical activity and more sedentary behavior than normal-weight children p < 0.05). Increased physical activity p < 0.01) and number of breakfasts eaten with family p < 0.05) were associated with decreased BMI z-score and percent body fat. Decreased sedentary behavior and sugar-sweetened beverage consumption were associated with decreased percent body fat p < 0.05) but not BMI. Conclusions: In this cohort of 271 children, increased physical activity and eating breakfast with family and reduced screen-based sedentary behaviors and sugar-sweetened beverage consumption were associated with more favorable trends in adiposity. Therefore, attention to these behaviors may be of particular importance. Results also suggest that future studies should include percent body fat as an outcome for a more precise assessment of the association of behavior with adiposity.