This thesis examines the relationship between obesity and health and health service use, and whether or not this relationship varies by socioeconomic status (SES). We start by generating hypotheses for this relationship based on a human capital model for health. We conduct a literature review on the topic and generate econometric models to be tested. We then provide an analysis of socioeconomic variation in the relationship between obesity and Health Related Quality of Life (HRQL). The results show that obesity is negatively associated with HRQL and that the negative association is more pronounced in lower SES individuals than higher SES individuals. We then conduct an analysis of socioeconomic variation in the association between obesity and HRQL in individuals with obesity-related comorbidities. The results show that the association between obesity and HRQL is more negative in individuals with these comorbidities than individuals without. Furthermore, it shows that obesity-related comorbidities are associated with greater reductions in HRQL in lower SES groups than in higher SES groups. We also examine SES variation in the impact of obesity on life expectancy and find that obesity increases mortality and reduces life expectancy. We find that the impact of obesity on mortality is more negative in lower SES women than in higher SES women. Mortality does not vary by SES groups in men. We then conduct an analysis of SES variation in the association between obesity and health service use. We use a range of health service indicators and find that obesity is associated with increased use. We also find that obesity will lead to greater use of some services in lower SES groups compared with higher SES groups. The main implication of this thesis is to illustrate that obesity can constitute different challenges across SES groups
