Experts say children's screen time should be limited to less than two hours each day.

Durban - To improve children’s cognitive skills such as problem solving, memory and attention, their screen time should be limited to less than two hours a day. This is the recommendation from experts, published this week in The Lancet Child & Adolescent Health journal.

The observational study, led by Dr Jeremy Walsh, of the Canadian children’s health research centre CHEO Research Institute, said children should have between nine to eleven hours of sleep, less than two hours of recreational screen time, and at least an hour of physical activity every day.

However, only one in 20 children in the US met the recommended guidelines.

“Behaviours and day-to-day activities contribute to brain and cognitive development in children, and physical activity, sedentary behaviour, and sleep might independently and collectively affect cognition. Evidence suggests that good sleep and physical activity are associated with improved academic performance, while physical activity is also linked to better reaction time, attention, memory, and inhibition,” said Walsh.

The results were compiled from data gleaned from 4,520 questionnaires from 20 sites across the USA, in which children and parents estimated the child’s physical activity, sleep and screen time. Children also completed a cognition test, which assessed language abilities, episodic memory, executive function, attention, working memory and processing speed.

“We found that more than two hours of recreational screen time in children was associated with poorer cognitive development. More research into the links between screen time and cognition is now needed, including studying the effect of different types of screen time, whether content is educational or entertainment, and whether it requires focus or involves multitasking. Based on our findings, paediatricians, parents, educators, and policymakers should promote limiting recreational screen time and prioritising healthy sleep routines throughout childhood and adolescence,” said Walsh.