From Coverage to Consequences: BMI, Health Behaviors, and Self-rated Health After Medicaid Contraction

Leveraging Tennessee's 2005 Medicaid contraction, I study the impact of losing public health insurance on body weight and relevant health behaviors. Using Behavioral Risk Factor Surveillance System (BRFSS) data from 1997 to 2010, I estimate synthetic difference-in-differences models. The estimates suggest that the reform increased Body Mass Index by 0.38 points and the overweight or obesity prevalence (BMI$\geq$25) by $\sim$4\% among Tennessean childless adults. My findings -- a 21\% increase in the share of childless adults reporting ``poor'' health status (the lowest level on the five-point scale), a reduction in Medicaid-reimbursed utilization of pain and anti-inflammatory medications, and a reduction in participation in moderate physical activities -- suggest that worsening unmanaged health conditions may be a key pathway through which coverage loss affected weight gain. Additionally, my analysis offers practical guidance for conducting robust inference in single treated cluster settings with limited pre-treatment data.