An Ecological Model of Weight Gain Among School-Age Children

Objective: Childhood obesity rates remain historically high in the United States. One way to conceptualize the many factors that contribute to obesity is through the use of an ecological model. There is a particular need to adapt and test this type of comprehensive model among vulnerable racial/ethnic and socioeconomic groups. Method: Using a large sample of U.S. youth (n = 8,225) drawn from the ECLS-K:2011, this project applied an ecological model of childhood obesity from kindergarten to second grade, including factors such as child physical activity, child screen time, child bedtime, family physical activity, family food insecurity, family meals, and neighborhood safety. The contributions of each of these factors across racial/ethnic, socioeconomic, and income-to-needs groups were examined concurrently and longitudinally. Results: Among the full sample, the largest standardized effect on weight was for income-to-needs ratio. Moving from above to below 200% of the poverty line resulted in an increase of .12 standard deviations in BMIz. Multigroup analyses indicated that there was only a significant difference in model fit based on race/ethnicity. Among Latino youth, income-to-needs ratio was a significant negative predictor of kindergarten BMIz; however, this effect was not significant among Black/African American youth. Conclusions: Overall, income-to-needs ratio emerged as the strongest link to obesity among the early elementary school years; this was particularly present among Latino youth.