Screen time, physical activity, and suicidality

In this study from DRISP, Rasmussen and colleagues examine how screen time and physical activity at age 11 are associated with suicide-related behavior in adolescence.

A total of 28,613 children from the Danish National Birth Cohort (DNBC) participated (17,101 girls and 11,512 boys) and were followed until age 18. Screen time was assessed as the average number of hours spent in front of a screen per day (<2, 2–4, 4–6, ≥6 hours), while physical activity was evaluated based on participation in sports and activity level during leisure time. Suicidal behavior was defined as none, suicidal thoughts, or suicide attempts (both self-reported and hospital-registered).

The results showed that high screen time was associated with an increased risk of suicidal behavior, particularly among girls. Girls with ≥6 hours of daily screen time had a 1.7 times higher risk of suicidal thoughts and twice the risk of suicide attempts compared to those with less than 2 hours of screen time. Among boys, the association was weaker for suicidal thoughts but more pronounced for attempts (aRRR 3.6). Low physical activity, on the other hand, was a strong risk factor for both genders — for both suicidal thoughts (aRRR ≈ 2.1) and attempts (aRRR ≈ 2.3). The combination of high screen time and low physical activity was especially harmful, resulting in nearly a threefold increase in the risk of suicide attempts. The analysis also indicated that boys with low physical activity were vulnerable regardless of their amount of screen time.

The study concludes that both sedentary behavior and physical inactivity early in childhood can have long-term mental health consequences and increase the risk of suicide-related behavior. The authors emphasize that prevention efforts should focus on promoting physical activity, limiting screen time, and supporting parents and schools in fostering healthy habits, as lifestyle and mental well-being are closely linked even before puberty.