Parental Work Hours and Childhood Obesity: Evidence using Instrumental Variables Related to Sibling School Eligibility
This study exploits plausibly exogenous variation from the youngest sibling’s school eligibility to estimate the effects of parental work on the weight outcomes of older children in the household. Data come from the 1979 cohort of the National Longitudinal Survey of Youth linked to the Child and Young Adult Supplement. We first show that mothers’ work hours increase gradually as the age of the youngest child rises, whereas mothers’ spouses’ work hours exhibit a discontinuous jump at kindergarten eligibility. Leveraging these insights, we develop an instrumental variables model that shows that parents’ work hours lead to larger increases in children’s BMI z-scores and probabilities of being overweight and obese than those identified in previous studies. We find no evidence that the impacts of maternal and paternal work are different. Subsample analyses find that the effects are concentrated among advantaged households, as measured by an index involving education, race, and mother’s marital status.
We thank Barry Hirsh, Rachana Bhatt, Sara Markowitz, James Marton, Kurt Schnier, Darren Lubotsky, and seminar participants at the Southern Economic Association Annual Meeting and the Western Economics Association Annual Conference. We also thank Patricia Anderson for sharing parameter estimates from Anderson et al. (2003). This research was conducted using restricted data from the Bureau of Labor Statistics. The views expressed in this paper do not reflect those of the BLS. The views expressed herein are those of the authors and do not necessarily reflect the views of the National Bureau of Economic Research.