Project Summary Sexual minorities have been found to have an increased burden of several cancer risk factors, including tobacco use, alcohol consumption and obesity. Over the last decade, there has been substantial advancement in the identification of social and contextual factors related to sexual minority health, and exposure to structural stigma has been implicated as a potential explanatory factor this disparity. Thus, intervening on factors related to structural stigma could be a promising approach for reducing the burden of cancer risk factors among this highly marginalized community. Evidence suggests that effects of exposure to stigma during adolescence could be different than stigma in later years, and prior studies that have attempted to examine these lifecourse effects. However, this research has major gaps. First, these studies were not nationally representative. Second, they did not explicitly use lifecourse methods to evaluate these effects. Thus, our study proposes to explore the effects of lifecourse exposure to structural stigma on tobacco use, heavy alcohol consumption, and being overweight or obese using a nationally representative dataset. The goal of this proposal is to evaluate lifecourse effects of exposure to structural stigma on sexual minority engagement in cancer risk factors. Using publicly available administrative datasets, we will update and refine a previously constructed state-level measure of structural stigma that was created in 2011 by including more granular county-level components that have been demonstrated to be important for the health of sexual minorities (aim 1). Using data from four waves of the National Longitudinal Study of Adolescent to Adult Health, we will apply this updated measure to evaluate the effects of life-course exposure to structural stigma on cancer risk factors among sexual minorities (aim 2). Finally, we will estimate the intersectional effects of exposure to structural stigma by gender, race/ethnicity, and socioeconomic status (aim 3). The interdisciplinary training environment for this proposal will provide the applicant an opportunity to enhance methodological skills, build research competency, and augment content expertise in order to become an expert in the intersection of cancer prevention and sexual minority health.