The impact of maternal employment on children's adiposity: Evidence from China's labor policy reform

Background China has experienced a rapid growth in childhood adiposity in recent years. Although a large number of studies examine the effect of maternal employment on children's adiposity in developed countries, only a few studies investigate the issue in developing countries. Moreover, existing studies tend to suffer from a potential endogeneity issue. Aims We provide new evidence on the causal effect of maternal employment on children's adiposity in China. Materials and methods We employ a difference‐in‐difference strategy that takes advantage of China's 1995 legislative change to labor regulations, which reduced the number of workdays from 6 to 5 days per week. Using longitudinal data from the China Health and Nutrition Survey (CHNS), we compare children whose mothers are wage‐earning employees to those whose mothers are self‐employed because the reform only affected the former. Results Although maternal employment and childhood obesity in China exhibits the same positive association as in the United States, our difference‐in‐difference estimates present a different picture. We find that a reduction in the maternal labor supply led to children's weight gain. Further investigation reveals that the effect was stronger among children who were male, younger, in urban areas, and from households with low socioeconomic status. Discussion Our evidence suggests that a change in maternal behaviors was likely responsible for children's weight gain. In particular, a greater proportion of treatment group mothers cooked and also devoted more time to cooking after the reform, which led to an increased caloric intake by their children. Such weight gain was beneficial for children who were previously underweight but harmful to those who became overweight. Conclusion The finding implies that additional maternal time at home likely has a different effect in China compared to the United States.