This study examined proposed direct and mediating relationships in the Structural Influence Model (SIM) of Communication within the chronic disease context. Using data from the Annenberg National Health Communication Survey (N = 14,472), we tested the potential mediating roles of information seeking, information scanning, and social capital between social determinants of health and four chronic disease risk behaviors: exercise level, fruit and vegetable intake, cigarette smoking, and excessive alcohol use. Information seeking, information scanning, and social capital received support as potential mediators. Our results are largely consistent with predictions of the SIM and highlight the important role of communication in reducing health risks and increasing healthy behaviors.