How two hours of screen time can harm your child’s health

Two hours of screen time each day is enough to trigger depression or physical illness in children. Experts reveal what parents need to know.

Two hours of screen time each day is enough to “dumb down’’ children or trigger depression or physical illness, an alarming global study reveals.

The Australian-led study of 577,000 children from 42 wealthy nations, published in The Lancet on Wednesday, shows that girls suffer ill-health after just two hours watching screens including television, social media or online gaming.

Boys can safely spend twice as much time online, with four hours of screen time daily before suffering health problems.

As psychiatrists warn of rising anxiety and depression among Australian children, the landmark study highlights the urgent need to balance screen time with “green time’’ outdoors.

Kids who exercise or play outdoors regularly are healthier and happier, the study shows.

Screen Time

Lead author Asaduzzaman Khan, associate professor of biostatistics and epidemiology at the University of Queensland, said the study found boys are twice as likely as girls to meet health guidelines for physical activity of an hour each day.

He said 24 per cent of boys, compared to 14 per cent of girls, spent an hour a day exercising.

“We found there were some benefits during the first hour of daily screen use, but detrimental effects … on mental wellbeing kick in after 75 minutes in girls and 105 minutes in boys,’’ he said.

“The (health) detriment starts after two hours of screen time for girls, and four hours for boys.

“Boys are more involved in outdoor activities than girls.’’

Children need more time outdoors to stay healthy.

The study found that children’s mental wellbeing could improve by cutting back on screen time and increasing physical activity.

The recipe for mental wellbeing was an hour of physical activity, and no more than two hours a day using screens, apart from schoolwork.

Dr Khan said too much time spent watching TV, gaming or social media could lead to “decreased cognitive abilities’’.

“Excess screen time effects can include depression, obesity, poor quality of life, unhealthy diet and decreased physical and cognitive abilities,’’ he said.

“If you spend more time on screens you are likely to not do well in your academic performance.’’

The global study, in collaboration with the University of NSW, Queensland University of Technology and Queen’s University in Canada, analysed data measuring screen time, physical activity, mental health indicators and physical ailments reported by 577,000 children aged 11, 13 and 15 from 42 wealthy countries.

It found that recreational screen time – excluding school work – averaged 6.3 hours for boys and 5.4 hours for girls.

Dr Khan said the children were surveyed before the start of the Covid-19 pandemic, which has kept children cooped up indoors and home schooling on screens.

“The situation is much worse now,’’ he said.

“My advice to parents is we need to exchange screen time for green time.

“I know this is challenging but if we try, we can do something … in relation to the mental health of our kids.’’

The Australian Medical Association is concerned about rising rates of obesity and mental illness among children glued to online games and social media.

“Screenagers” who spend a third of their waking hours glued to screens are growing short sighted, clumsy and even showing signs of autism, medical experts have warned.