Laugh and grow fat: Happiness affects body mass index among Urban Chinese adults.

Previous studies have extensively examined the relationship between body mass index (BMI) and subjective well-being (SWB) but have mainly focused on the effects of BMI on SWB, leaving the question of whether BMI can be influenced by SWB largely neglected. In this study, we present the first empirical evidence on the effects of SWB on BMI among adults, using data combined from four waves of the Chinese General Social Survey (CGSS) (2010-2013). We find that, among urban Chinese adults, those who have a higher level of happiness tend to have higher BMI, after extensively controlling for a constellation of individual sociodemographic and health attributes. Further analyses using the instrumental variable method and propensity score matching provided similar results.