Signal Two Hours of Daily Social Media Linked to Teen Depression (longitudinal 10-year)

Summary

A ten-year longitudinal study conducted through the Child to Adult Transition Study (CATS), led by the Murdoch Children's Research Institute and Deakin University, followed almost 1,200 children in Melbourne from age nine to nineteen, gathering annual data on social media use and mental health indicators including depression, anxiety, well-being and self-harm. The research found that more than two hours of daily social media use significantly raised depression risk one year later, with the peak psychiatric-risk velocity concentrated among girls aged 12 to 13. Findings were reported around 11-12 June 2026, roughly six months into Australia's under-16 social media restrictions, which took effect 10 December 2025. Researchers, including Dr Nandi Vijayakumar, stressed a balanced view, noting social media is not universally harmful and many adolescents report positive experiences with online community, creativity and self-expression. The MCRI/Deakin team is separately monitoring the impact of Australia's age restrictions through the Connected Minds Study, tracking 13- to 16-year-olds' use of apps such as Instagram, TikTok, Snapchat and YouTube before and after the ban.