This study examines user behaviors in online health communities (OHCs) through a mediated-moderated model grounded in the health disclosure decision-making framework. Preliminary findings indicate that information stigma increases concise disclosures, whereas information anxiety drives detailed sharing, both enhancing the helpfulness of support responses. Information tone significantly moderates these relationships. The study contributes to theory by clarifying disclosure dynamics and offers practical recommendations for OHC managers and users to optimize support exchanges.