The social contingency of weight: National obesity prevalence as a moderator of the link between individual obesity and mental health

This study examines whether national obesity prevalence moderates the association between individual Body Mass Index (BMI) and mental well-being. Drawing on insights from minority stress theory and sociological research on the framing of obesity as a health crisis, we analyze how the relationship between body weight and mental health varies across national contexts. Using data on 58,274 respondents from 21 countries in the International Social Survey Programme (ISSP) Health and Health Care modules (2011 and 2021), our results reveal that the psychological burden of weight is not universal. While we find little or no mental health penalty for higher BMI in contexts where obesity is less common, the negative association between body weight and mental well-being sharpens dramatically in high-prevalence societies. These findings suggest that the psychological consequences of body weight are deeply shaped by the broader social environments and societal norms surrounding obesity.