The period of adolescence is a transitional developmental stage, critical in shaping health trajectories across the life course. While many individuals traverse the adolescent transition relatively unscathed, a number suffer from significant health problems from adolescence to adulthood. Recent studies have begun to investigate the biological mechanism through which social conditions early in the life course influence health trajectories. Previous research on allostatic load, an indicator of physiological dysregulation resulting from the wear and tear of stress, has focused on adults and the aging, but few have explored allostatic load among adolescents. Additionally, recent literature has begun to explore the mechanisms through which social conditions during adolescence lead to changing obesity patterns during the transition to adulthood, though none have considered the mediating mechanism of stressful life events.

Using data from two nationally representative samples of adolescents age 12 to 19 years, the National Health and Nutrition Examination Survey (NHANES) (N = 8,431) and the National Longitudinal Study of Adolescent Health (Add Health) (N = 9,311), the overarching goals of this study were (1) to investigate sociodemographic correlates of AL across adolescence from age 12 to 19 years, and (2) to determine whether stressful life events (SLE) in adolescence explain the relationship between adolescent sociodemographic factors and longitudinal patterns of obesity from adolescence to young adulthood. The research for this dissertation drew upon life course, social stratification, and stress process theories.

Specific significant differences in AL among adolescents by age and race/ethnicity were found. In particular, higher AL scores, suggestive of greater cumulative physiological dysregulation, were significantly associated with older age and Black race/ethnicity. Select significant mediating pathways of adolescent SLE on becoming obese among males were also found. Mediation analysis revealed that SLE done to adolescent males partially explained the relationship between age and low family income on becoming obese over time. Surprisingly, no significant mediating effects of adolescent SLE on longitudinal obesity patterns were found among females.

This study provided the first examination of associations between major sociodemographic factors and AL among a nationally representative sample of adolescents. The concept of AL offers great promise toward expanding our understanding of how social and environmental factors are embodied within our biological regulatory systems, and translated into disease outcomes and health disparities. The present research has significant implications for informing health prevention interventions among younger populations. Additionally, by focusing on the intervening mechanism through which adolescent social conditions may affect obesity, this research contributes to an understanding of the processes of obesity development during childhood and adolescence. These findings point to possible interventions that can prevent obesity among young males who are from low SES households. Recommendations regarding stress management and coping mechanisms could aid in the fight against the increasing obesity epidemic among the younger population.