Children should not be allowed to use smartphones until they are 13 and should be banned from accessing conventional social media such as TikTok, Instagram and Snapchat until they are 18, according to a report by experts commissioned by Emmanuel Macron.

The French president had asked scientists and experts to suggest screen use guidelines for children with a view to France taking unprecedented steps on limiting their exposure. It was unclear how the government might now proceed after the report’s publication. Macron said in January: “There might be bans, there might be restrictions.”

The hard-hitting report said children needed to be protected from the tech industry’s profit-driven “strategy of capturing children’s attention, using all forms of cognitive bias to shut children away on their screens, control them, re-engage them and monetise them”.

Children were becoming “merchandise” in this new tech market, the report said, adding: “We want [the industry] to know we’ve seen what they’re doing and we won’t let them get away with it.”

A three-month study by scientists and experts led by a neurologist, Servane Mouton, and Amine Benyamina, the head of the psychiatry and addiction service at Paul-Brousse hospital, said children under three should have no exposure to screens – television included – and no child should have a phone before the age of 11.

Any phone given to a child aged between 11 and 13 should be a handset without access to the internet, it said, setting the minimum age at which they should be allowed a smartphone connected to the internet at 13.

The report said a 15-year-old should be able to access only what it called “ethical” social media, such as Mastodon. Conventional, mass-marketed, profit-driven social media such as TikTok, Instagram or Snapchat should not be available to teenagers until they reached 18, it found. Teenagers should also receive better education on the science behind the need to get enough sleep.

The report made equally stringent recommendations for the very young, saying phones and screens should be limited as much as possible on maternity wards to help parents bond with their babies. Phone use should also be addressed among childminders, it said.

For children up to the age of six, screens of all kinds should be “strongly limited” and only very rarely used for education content when sitting with an adult. Screens should be totally banned from nursery schools for children under six. In primary schools, children should not be given individual tablets or digital devices to work on, unless it was for a specific disability.

The report also suggested banning connected toys, except those used as audio for storytelling.

“Before the age of six, no child needs a screen in order to develop,” Mouton said. “In fact, screens can stop them developing properly at this age.”

The scientists said they did not want to chide parents, who themselves were “victims of a powerful tech industry”. They said parents should instead be helped to avoid what they called “techno-ference” – when parents constantly checking their own phones interfered with their ability concentrate on talking to, eating with or playing with their children.

This was harming young people’s emotional development, the report said. It included adults scrolling on their phones while feeding young children, or homes where a television was constantly on in the background.

Scientists said parents were not to blame and more should be done in society as a whole, such as allowing adults to properly disconnect from work out of hours, limiting screens in public places, introducing screen-free restaurants and cafes, or parents putting their phones in a box when they got home from work.

The scientists said “parental controls” should not be seen as a sufficient means of protecting children. Rather, they were an ineffective distraction, peddled by the tech industry “to get itself off the hook” for creating algorithms, particularly within social media, designed to addict and monetise children.

Benyamina said: “Tech is and will remain a fantastic tool, but it has to act in people’s service, not people being reduced to serving a product.”

He said screens had negative effects on children “in terms of their eyesight, their metabolism … their intelligence, concentration and cognitive processes”.

He said addictions to screens were not to the product itself but to content. He said: “Algorithms that re-engage and stimulate the pleasure system and are built to avoid you losing interest in the content have a type of addictive dynamic.”

He said people should be vigilant on social media if they noticed that content was re-engaging them. “If you decided you wanted to look at one or two videos and you were on it all evening, you need to question it.”