Mental and physical health: the mediating role of physical activity

Mental health problems are on the rise and affect the lives of millions of people globally. Research has shown that individuals with better mental health tend to have better physical health, but the mechanisms behind this relationship are not well understood. The current study focuses on the potential role of physical activity, smoking, and alcohol consumption as mechanisms through which mental health affects physical health. To address the endogeneity of mental health, we use an instrumental-variables model that incorporates individual-level fixed effects. We find that better mental health leads to increased physical activity, which is associated with better physical health. Our results highlight the importance of policies that promote physical activity as a means of enhancing physical health.