Self-Expression and Sharing around Chronic Illness on TikTok.

While prior work has investigated the benefits of online health communities and general-purpose social media used for health-related purposes, little work examines the use of TikTok, an emerging social media platform with a substantial user base. The platform's multimodal capabilities foster creative self-expression, while the content-driven network allows users to reach new audiences beyond their personal connections. To investigate users' challenges and motivations, we analyzed 160 TikTok videos that center on users' firsthand experiences living with chronic illness. We found that users struggled with a loss of normalcy and stigmatization in daily life. To contend with these challenges, they publicly shared their experiences to raise awareness, seek support from peers, and normalize chronic illness experiences. Based on our findings, we discuss the modalities of TikTok that facilitate self-expression around stigmatized topics and provide implications for the design of online health communities that better support adolescents and young adults.