ABSTRACT
The prevalence of childhood obesity in the United States has more than tripled over the last four decades from 5 percent in 1978 to 18.5 percent in 2016. There is evidence for a break in trend in recent years: after growing from 0.4 to 0.7 percentage point per year between 1978 and 2004, the rate of increase has slowed to 0.1 percentage point per year from 2004 to 2016. To better understand these trends, in this paper we analyze a range of datasets that collect information on childhood obesity. We analyze the data overall, across the age distribution, across birth cohorts, and for subgroups of interest. We find steady increases in cohort-level obesity prevalence through approximately age 10, with levels unchanged thereafter, suggesting a need for additional interventions at early ages. We find that the prevalence of obesity has diverged by race and gender in recent years, especially among children entering kindergarten. Compared with 5-year-olds in 1997, 5-year-olds in 2010 were 2 percentage points more likely to be obese overall. Black and Hispanic 5-year-olds were 5 and 3 percentage points more likely to be obese, respectively, while whites had a 1 percentage point increase in obesity. However, overall and among all subgroups the rate of growth in obesity from kindergarten through 3rd grade has declined in recent years. Together, these findings can inform a future research literature that aims to target obesity interventions where they will be most impactful.
Subject(s)
Pediatric Obesity/epidemiology , Adolescent , Black or African American , Age Distribution , Child , Child, Preschool , Cohort Studies , Female , Hispanic or Latino , Humans , Male , Pediatric Obesity/ethnology , Prevalence , Racial Groups , Sex Distribution , United States/epidemiology , White PeopleABSTRACT
In this paper, we investigate the impact of attending school on body weight and obesity using a regression-discontinuity design. As is the case with academic outcomes, school exposure is related to unobserved determinants of weight outcomes because some families choose to have their child start school late (or early). If one does not account for this endogeneity, it appears that an additional year of school exposure results in a greater BMI and a higher probability of being overweight or obese. When we compare the weight outcomes of similar age children with one versus two years of school exposure due to regulations on school starting age, the significant positive effects disappear, and most point estimates become negative, but insignificant. However, additional school exposure appears to improve weight outcomes of children for whom the transition to elementary school represents a more dramatic change in environment (those who spent less time in childcare prior to kindergarten).
Subject(s)
Body Mass Index , Obesity/epidemiology , Schools , Social Environment , Age Distribution , Child , Empirical Research , Female , Humans , Male , Regression Analysis , United States/epidemiologyABSTRACT
This paper seeks to determine whether a causal relationship exists between maternal employment and childhood weight problems. We use matched mother-child data from the National Longitudinal Survey of Youth (NLSY) and employ econometric techniques to control for observable and unobservable differences across individuals and families that may influence both children's weight and their mothers' work patterns. Our results indicate that a child is more likely to be overweight if his/her mother worked more hours per week over the child's life. Analyses by subgroups show that it is higher socioeconomic status mothers whose work intensity is particularly deleterious for their children's overweight status.
