The effect of broadband internet on children's weight: Evidence from China

This study employs ten-wave data from the China Health and Nutrition Survey (CHNS), covering the period from 1989 to 2015. It leverages the nationwide internet speed upgrading project launched in the early 21st century as an exogenous shock. Using this variation, we construct a difference-in-differences model to identify the causal effect of broadband internet access on children’s weight outcomes. The results show that broadband internet significantly increases the probability of children being overweight. Robustness tests support these results. The heterogeneity analysis reveals that the weights of children who are older and in urban are more affected by broadband internet. Mechanism analysis reveals that broadband internet increases children’s sedentary game activities time, decreases their physical activities time, and increases their snack intake and total energy intake. This study underscores the significance of coordinated regulation of children's gaming activities by parents, schools, communities, and the government, in order to effectively reduce children's online game time, mitigate the risk of overweight, and alleviate the economic burden associated with childhood overweight.