Weight stigma and engagement in physical health behaviours among young adults in India.

Background: Weight stigma - bias, prejudice, and discrimination based on weight - affects engagement in physical health behaviours in Western populations. Effects on individuals from South Asia, particularly India, are less well understood. Objective: This study examined whether weight stigma is associated with young Indian adults' engagement in physical health behaviours and explored potential moderators and mediators. Methods: 781 adults (18-26 years) completed an online survey. Multiple regression analyses assessed whether experienced (EWS), anticipated (AWS), and internalised (IWS) weight stigma is associated with engagement in physical health behaviours while controlling for self-reported BMI, gender, age, and income, whether effects were mediated by stress and self-esteem, and moderated by perceived weight status and BMI. Results: EWS, AWS and IWS were significantly associated with greater engagement in unhealthy and extremely unhealthy weight control behaviours, alcohol consumption, and binge eating with and without loss of control. EWS was also associated with greater cigarette use. AWS and EWS were associated with lower physical activity. While stress more consistently mediated the relationship between weight stigma and health behaviour, self-esteem emerged as a novel mediator. Perceived weight status was a more consistent moderator than BMI. Discussion: This is the first study to provide evidence that weight stigma is associated with greater engagement in unhealthy behaviours and less engagement in healthy behaviours in young Indian adults. Mediation by stress supports COBWEBS and the Weight-Based Social Identity Threat Model, while self-esteem emerged as a novel mediator. These findings offer insights into mechanisms linking weight stigma to physical health behaviours and the impacts of weight stigma within a non-Western setting.