Abstract
How young adults access health information has changed rapidly with the rise of social media, and Instagram influencers in particular. Therefore, it is critical to analyse whether this new wave of Instagram health influencers is strictly beneficial to the physical and mental health of their followers. This thesis utilises a mixed-methods design to investigate the health and well- being of young adults who follow health influencers. In Study 1, 1022 young adults completed a quantitative survey of lifestyle habits, and their mental health and well-being. Results showed that young adults who follow health influencers reported higher levels of vigorous exercise, greater fruit and vegetable intake, higher well-being and greater distress compared to non- followers. Moreover, moderator analyses showed that following health influencers disrupted the typically positive relationship between health behaviours and distress. Specifically, among health influencer followers, engagement in healthier behaviours was associated with higher distress levels. Study 2 probed these findings further in a qualitative focus group study consisting of 19 young women, and found that health influencers could positively and negatively impact health and well-being, sometimes simultaneously. Influencers with greater expertise and body positivity linked to positive outcomes. Influencers that were more appearance-focused and followers of younger age were linked to negative outcomes. In this qualitative investigation, upwards social comparison was identified as a potential mechanism behind poor outcomes associated with following health influencers. These findings taken together suggest there are positive and negative aspects to following health influencers, which are often due to the relationship the follower has with the influencer. Ensuring positive outcomes and preventing negative outcomes of following health influencers for young adults is of utmost importance.