Abstract
How young adults access health information has changed rapidly with the rise of social media and the new wave of Instagram health influencers. Therefore, it is important to investigate whether following health influencers on Instagram is strictly beneficial to the physical and mental health of their followers. In this cross-sectional study, 1,022 young adults (aged 18-25) across New Zealand, the United States, and the United Kingdom, completed a survey in 2021 of their lifestyle habits including measures of social media usage, dietary and exercise habits, and mental health. Results showed that health influencer followers (HIFs) reported more vigorous exercise (p < .001), higher fruit and vegetable intake (p < .001), and better well-being (p < .001) but also greater distress (a factor comprised of depression, anxiety and negative mood; p = .006) compared to non-followers, controlling for age, gender, ethnicity, education level, socioeconomic status, and body mass index. Higher distress was especially pronounced among those who followed food or diet-related health influencers (p < .001). Moreover, following health influencers disrupted the typical protective relationship between health behaviours and distress. Among health influencer followers, more vigorous physical activity was associated with higher distress levels. This was in sharp contrast to the lack of a relationship for non-followers, and the typical protective relationship in non-users of Instagram. These findings suggest that following health influencers may disrupt the positive relationship between health behaviours and mental health. Followup research exploring prospective patterns could reveal the exact impact of following health influencers on mental health.