All screens toxic for teen health after just two hours of use

Whether it is watching television or playing electronic games, teenagers are experiencing serious physical and mental health consequences after just two hours of screen use, according to University of Queensland-led research.

UQ School of Health and Rehabilitation Sciences researcher Associate Professor Asad Khan said the global study of more than 400,000 adolescents is the first to provide evidence that both passive and mentally active screen time adversely affects teens' mental wellbeing.

"Teens need to be limited to less than two hours per day, whether it's passive screen time which includes watching a TV series and scrolling on social media or mentally active screen time, like playing computer games or using a computer for entertainment purposes," Dr. Khan said.

"We found teens are more likely to report psychosomatic symptoms, a combination of physical and psychological complaints, if they exceed two hours of screen time and these effects were similar regardless of physical activity levels.

"Psyche stands for mind and soma stands for body, and it is no longer possible to separate mind and body, which is why we looked at psychosomatic complaints together.

"Psychological complaints from teens included feeling low, irritable, nervousness and sleeping difficulty, and somatic complaints included headaches, abdominal pain, backache and dizziness."

Key study findings showed teen boys who watched more than four hours of television per day, compared with those who watched less than two hours per day were 67% more likely to report high psychosomatic complaints while girls were at slightly higher risk at 71%.

Adolescents who exceeded four hours of playing electronic games had a 78% higher risk in boys and 88% in girls of reporting high psychosomatic complaints.

High computer use for entertainment purposes was also reported to result in high psychosomatic complaints, with 84% higher risk in boys and 108% high in girls.

"The findings of this study are concerning as screen use in teens has increased significantly in recent decades, but we know little about the effects of different types of screen use on mental and physical health," Dr. Khan said.

"Our findings support existing public health recommendations of limiting screen use to a maximum of two hours per day for improved health and wellbeing outcomes of teens.

"We hope this work contributes towards the global debate on 'how much is too much' screen use for teenagers and builds pressure around reducing discretional screen time to optimize health and wellbeing of adolescents."

The research was conducted in collaboration with Queen's University and University of Ottawa, Canada.

The study is published in American Journal of Preventive Medicine.