A Psychobiobehavioral Expansion of the Cyclic Obesity/Weight-Based Stigma (COBWEBS) Model in Adolescents With Overweight and Obesity

Abstract

The Cyclic Obesity/Weight-Based Stigma (COBWEBS) model is an original, theory-based framework that describes how stress from obesity- and weight-stigma promotes weight gain among individuals of higher weight. Though the COBWEBS model advances our understanding of how stress promotes weight gain, gaps within the model related to physical activity (PA), metabolic risk, and the psychological constructs underlying PA and eating behaviors remain. Using primary and secondary data analysis, this dissertation expands the COBWEBS framework to address these gaps. Study 1 of this dissertation examined the association between stress, objectively measured PA, and the moderating effect of PA enjoyment among adolescents with overweight/obesity. Greater stress was found to be associated with lower enjoyment of PA. However, stress was not associated with objectively measured PA, nor was PA enjoyment a significant moderator. Findings from study 1 suggests that increased stress may exert more immediate effects on factors preceding PA, which may ultimately lead to decreased participation in PA among adolescents with overweight/obesity. Study 2 of this dissertation examined the association between acute stress, caloric intake, and the moderating effect of disordered eating behavior in adolescents with overweight/obesity. Acute daily stressors were associated with greater caloric intake. Disordered eating behavior moderated the association between acute stress frequency and caloric intake, but not between acute stress sum and caloric intake. Findings from study 2 suggests that greater exposure to acute daily stressors may increase food intake in adolescents with overweight/obesity, with greater susceptibility among those with high levels of disordered eating. Study 3 of this dissertation examined biobehavioral pathways linking stress to metabolic risk in adolescents with overweight/obesity. Stress was not association with metabolic risk, nor was PA, caloric intake, or cortisol significant mediators. However, racial differences in metabolic risk was observed. Specifically, higher levels of stress was associated with lower insulin sensitivity (Si) among Black adolescents, whereas the inverse association was observed for White adolescents. Study 3 findings suggest that stress may uniquely influence racial differences in metabolic risk among Black and White adolescents with overweight/obesity. Study 4 of this dissertation examined the association between weight stigma exposure and health-promoting intentions and behaviors among older adolescents. It was observed that prior weight stigma experiences were associated with PA avoidance. However, prior weight stigma experiences was not associated with positive PA or eating intentions, nor were there any differences in positive PA intentions, PA avoidance, or eating intentions and behaviors among participants. Study 4 findings indicate that greater weight stigma experiences may lead to higher avoidance of PA. Together, findings from these studies suggests that psychological stress affects behavioral antecedents such as physical activity enjoyment, and that greater susceptibility to the effects of stress on eating behavior is pronounced among those with disordered eating behavior. Additionally, the stressor of weight stigma leads to the habitual avoidance of engaging in PA. Upstream, preventative approaches addressing these behavioral precursors may help interrupt the cycle of stress and weight gain among adolescents with overweight/obesity.