Attention parents with toddlers and “screenagers”. Sweden’s public health agency, Folkhälsomyndigheten, has said babies should not be allowed to watch screens at all while teenagers should have no more than three hours of screen time a day.

The figures represent a sharp cutback on the current average screen time restrictions in Sweden. The suggestion is to cap daily screen use in the two-to-five age group to a maximum of one hour, children between six and 12 should not have more than two hours and then till age 18, it’s three hours. The current usage in Sweden is four hours a day for the 9-to-12 age group and more than seven hours a day (minus homework) for 17/18-year-olds.

“There are millions and millions of neurons in a child's brain and as a child is growing, these neurons develop a rich connection with each other. The number of shoots and branches is constantly growing. Making this possible are human interactions and stimulation. It’s like serve-and-volley: A child smiles and you smile back or a child talks and you reply. It’s a constant dyadic interaction that enhances nerve connections within the brain. Too much screen time makes a child a passive absorber and the serve-and-volley interaction does not happen. Thus, screen time impacts brain growth adversely. The younger a brain is, the more it suffers,” Dr Jai Ranjan Ram, senior consultant psychiatrist, told The Telegraph.

The Indian Academy of Paediatrics issued “screen time guidelines for parents” a few years ago. They recommended that children below age two “should not be exposed to any type of screen except for occasional video call with relatives”. For those in the two-five age group, “it should not exceed one hour”.

They wrote: “For older children and adolescents, it is important to balance screen time with other activities that are required for overall development. These activities include an hour of physical activity (playtime), adequate duration of sleep (adolescents require eight-nine hours of uninterrupted sleep at night), and time for schoolwork, meals, hobbies and family time.”

China, which has 1.1 billion Internet users, was early in proposing rules to separate teenagers from smartphones. Under the draft regulations released by the Cyberspace Administration of China (CAC), a “minor mode” feature would limit 16- and 17-year-olds to two hours of Internet usage a day.

For 8-to-15-year-olds, it would be restricted to one hour and for those under eight, usage would be limited to 40 minutes a day. The mode would also stop minors from using apps (beyond educational) between 10pm and 6am, the draft said.

In the US, California governor Gavin Newsom is trying to “get smartphones out of schools”.

His recent call to action follows demands from parents to protect children from harms associated with smartphones and social media where cyber bullying and body image issues are rampant.

In July, the US Senate passed the Kids Online Safety Act (KOSA) and the Children and Teens’ Online Privacy Protection Act, the first important Internet bills meant to protect children.

In the UK, Prime Minister Keir Starmer is not in favour of a smartphone ban among children under 16.

He told ITV: “Generally, I do think we should look at what is available online to children, but in relation to simply banning phones for under-16s, I don’t think that’s a good idea. I don’t think that’s a practical way forward.”

In April, communications regulator Ofcom showed that a quarter of three- and four-year-olds in the UK now own a smartphone, while half of children under 13 are on social media.