Amid the worsening teen mental health crisis and new legislation proposing to ban children under 16 from using social media, a new study finds that greater screen time among children aged 9–11 is associated with a higher risk of developing suicidal behaviours two years later.

The study, published in the journal Preventive Medicine, finds that each additional hour of screen time is associated with a 9% higher risk of reporting suicidal behaviour two years later. In particular, each extra hour spent watching videos, playing video games, texting, and video chatting led to a higher risk of suicidal behaviour.

“Screen usage could lead to social isolation, cyberbullying, and sleep disruption, which could worsen mental health,” said senior author, Jason Nagata, MD, assistant professor of paediatrics at the University of California, San Francisco. “More time on screens often displaces time for in-person socialising, physical activity, and sleep.”

The study builds upon the existing knowledge surrounding the youth mental health crisis. Suicide is the second leading cause of death among adolescents. The study extracts data from the nationwide Adolescent Brain Cognitive Development (ABCD) study, the largest long-term study of brain development in the United States. The study collected screen time data for 11,633 children 9-11 years who were followed for two years. The children answered questions about their time spent on six different screen time modalities as well as suicidal behaviours.

“The study was conducted mostly prior to the Covid pandemic, but its findings are especially relevant now since youth mental health worsened during the pandemic,” noted co-author Kyle T. Ganson, PhD, assistant professor at the University of Toronto’s Factor-Inwentash Faculty of Social Work. The researchers previously found that adolescent screen time doubled to nearly eight hours daily at the start of the pandemic in a 2021 study published in JAMA Pediatrics.

“Screen time can have important benefits such as education and socialisation, but parents should try to mitigate adverse mental health risks from excessive screen time. Parents should regularly talk to their children about screen usage and role model screen behaviours,” said Nagata.