Phone use and mental health in adolescents and young adults: the roles of loneliness and virtual social contact

Smartphone use among adolescents and young adults has raised concerns about its impact on mental health, with heavy use linked to negative outcomes. This study explored the mechanisms behind this relationship, focusing on loneliness, in-person social contact, and physical exercise as mediators, and different types of phone use —active virtual social contact and passive scrolling—as moderators. Using a cross-sectional online survey conducted in Austria, we assessed smartphone use and time spent on virtual social contact, passive scrolling, in-person social contact, and exercise, alongside various mental health outcomes. We found an overall association between phone use and depressive symptoms, anxiety, and wellbeing, which was mediated by loneliness. Virtual social contact moderated the association: individuals with lower engagement in virtual social contact experienced higher depression and anxiety with increased phone use, while those with higher engagement showed the reverse pattern. Passive scrolling did not moderate the relationship between phone use and mental health but was directly associated with poorer sleep and well-being. These findings suggest that loneliness plays a central role in the adverse effects of excessive smartphone use on mental health. Moreover, the impact of smartphone use is nuanced and depends on whether it fosters or inhibits meaningful social connections.