The longitudinal effects of social media on sleep among youth: A scoping review

Social media has become an integral part of our everyday lives, with nearly 5 billion users worldwide. Its ubiquity has sparked concerns about the potential effects on sleep, particularly among young people. Previous research has generally shown that greater social media engagement is associated with poorer sleep outcomes, such as later bedtimes and longer sleep onset latency. However, most evidence is cross-sectional, limiting causal claims. This scoping review synthesises longitudinal studies published in the last five years examining the impact of social media use on subsequent sleep in young people. In accordance with cross-sectional findings, the majority of studies (∼70 %) provide evidence of a negative impact of social media use on bedtime and sleep onset latency, particularly in relation to problematic social media use, including at bedtime. However, methodological limitations, such as heavy reliance on self-reports and non-validated measures of social media use and sleep, restrict the strength of these conclusions. Future studies should employ validated measures and move beyond frequency-based metrics of social media to explore how content, patterns of problematic use, and the timing of use influence sleep longitudinally. It will also be important to consider bidirectional pathways and interactions with other key variables such as neurodiversity, socioeconomic status and mental health. • Two-thirds of longitudinal studies link social media use to poor sleep. • Problematic and bedtime use show the strongest adverse effects. • Sleep onset times and latency are most consistently impacted. • Inconsistent findings are likely due to heterogenous methods. • Heavy reliance on self-report limits strength of conclusions.