The Effects of Old and New Media on Children's Weight

The aim of this paper is to determine if there is a causal relationship between children's time spent on media related activities and their weight. Since the beginning of 1980s, childhood obesity rates in the U.S. and other developed countries have been increasing. It has been suggested in the literature that changes in children's media use is an important explanation for the observed increase in children's weight. I investigate whether or not this hypothesis is supported by data. Additionally, I compare the eff ects of television, or old media, with the eff ects of computers and video games, or new media. The Child Development Supplement to the Panel Study of Income Dynamics is used for the analysis. To address the endogeneity of children's media use, I use the child fixed effects and correlated random eff ects models. I find no evidence that media use contributes to weight gain among children. On average, a one hour per week increase in a child's computer or video game time is estimated to decrease his/her body mass index slightly and to not aff ect significantly the probability of being overweight or obese. The estimated e ffects of television time on weight are not signi ficantly different from zero. These findings, especially the results related to children's computer or video game time, are robust to a number of sensitivity checks. Additionally, there is heterogeneity in the e ffects of media time by child and family characteristics