The Impact of ACA Medicaid Expansion on Health Behaviors

The U.S. population receives suboptimal levels of preventive care and has a high prevalence of risky health behaviors. One goal of the Affordable Care Act (ACA) was to increase preventive care and improve health behaviors by expanding access to health insurance.

This paper estimates how the ACA’s state-level expansions of Medicaid in 2014 affected these outcomes. Using data from the Behavioral Risk Factor Surveillance System, and a difference-in-differences model that compares states that did and did not expand Medicaid, we examine the impact of the expansions on preventive care (e.g. dental visits, immunizations, mammograms, cancer screenings) and risky health behaviors (e.g. smoking, heavy drinking, lack of exercise, obesity).

We find evidence consistent with increased use of certain forms of preventive care such as dental visits and cancer screenings but little evidence of changes in health behaviors and in particular no evidence of ex ante moral hazard (i.e., no evidence that risky health behaviors increased in response to health insurance coverage). The Medicaid expansions also resulted in modest improvements in self-assessed health and decreases in the number of work days missed due to poor health.