The effects of public health insurance on health behaviors: Evidence from the fifth year of Medicaid expansion

This study examines the longer term relationship between public health insurance expansions and health behaviors. I leverage geographic and temporal variation in the implementation of the Affordable Care Act‐facilitated Medicaid expansions and provide the first estimates of the expansions' behavioral impacts during their first 5 years. Using national survey data from the 2010 to 2018 Behavioral Risk Factors Surveillance System and a difference‐in‐differences regression design, I show that the Medicaid expansions increase utilization of certain forms of preventive care, while reducing heavy drinking. I also find suggestive evidence that the expansions reduce smoking and increase the probability of exercise. These results stand in contrast with earlier studies that used only 2 or 3 years of postexpansion data and found no detectable effect of the Medicaid expansions on health behaviors in the short run. My results, combined with evidence from previous studies, suggest that public insurance expansions may not prompt an immediate change in health behaviors, but newly eligible populations do increase investments in healthy behaviors over time. In the long run, Medicaid expansions may help reduce engagement in risky behaviors like drinking and smoking among low‐income people.