This dissertation uses a multi-level approach to assess how social determinants of health influence life course health trajectories through a structural intersectional lens. The three chapters assess a macrolevel, meso-level and microlevel exposure, respectively, over a range of physical, mental, physiological, and self-reported health measures. Longitudinal data from both the Survey on Income and Program Participation (SIPP) and the Health and Retirement Study (HRS) is used to integrate a life course approach to health into this work. The structural intersectionality perspective is employed by using multiple social positions of an individual (such as race-ethnicity-citizenship) when constructing categories for assessment, as opposed to relying on a series of interaction terms in the modelling process. Fixed effects models are used to isolate policy effects in chapter one, while both chapters two and three employ multilevel growth curve models to map life course health trajectories. The first chapter emphasizes macro-level exposure in the form of state immigrant policy contexts, considering how state immigrant policies influence anxiety and self-rated health at the intersection of race, ethnicity, nativity, and legal status. The second chapter addresses how meso-level processes in the form of neighborhood conditions moderate adult life course trajectories of aging across different intersectional statuses. The third chapter analyzes individual-level exposures in the form of stress exposure and appraisal while considering how these stressors differentially shape markers of health across various intersectional groups. This work contributes to the field in three major ways. First, by calling attention to the importance of looking within racial and ethnic groups to capture variation in health. The usage of intersectional identities rather than multiple interaction terms is a more succinct way to capture these health differences. Second, by properly accounting for timing and cumulative effects over life course exposures. The life course perspective with exposures that are age-specific add necessary context to how these societal exposures pattern health over the life course. Third, this multilevel approach to the social determinants of health allows for the examination of a range of health outcomes, capturing the multidimensional nature of population health and our assessment of it. Results from this work serve as an important extension of previous research, while serving to inspire future questions and expansion on the ideas presented in the chapters to follow.