Health officials in the Trump administration have issued an advisory about children and adolescents’ excessive screen time, warning that negative impacts on sleep and mental functioning have “become a public health concern”.

The advisory from the Department of Health and Human Services (HHS) notes that the amount of screen time reaches an average of four or more hours per day by the time a child becomes a teenager and can be linked to poor sleep, decreased functioning in school, less physical activity and weakened in-person relationships.

“A concern at all stages of life, and a particularly important one around children’s screen exposure, is its potential to disrupt healthy sleep, which is fundamental to learning, mood, behavior, physical health, and overall development,” the report says.

The department provided guidance about how to identify harmful behaviors around screens and how to set limits, including no screen time for children under 18 months old, less than one hour per day for children under six and two hours per day for ages six to 18.

“Exposure often begins before a child’s first birthday and increases as children age. By adolescence, children may spend more time on screens than sleeping or attending school,” the report says.

Efforts to limit screen time outside the US include legislation in Australia and India, which both prohibit children under 16 from holding accounts on major social media platforms as well as China’s “minor mode” program, which requires device-level restrictions ⁠and app-specific rules to restrict screen time depending on age. Many other countries are also considering similar bans.

Last month, the Los Angeles unified school district passed a resolution to restrict screen use in public education classrooms. The resolution sets screen time limits for each grade level, eliminates technology for those in first grade and below and bars student-led use of YouTube and other streaming platforms.

Separately, a court in New Mexico recently found Meta, the parent company of Facebook, liable for misleading consumers about the safety of its platforms and endangering children. A court in Los Angeles also found Meta and Google negligent in a social media addiction lawsuit.

The HHS advisory was compiled and published by agency officials because there is no confirmed surgeon general. Dr Stephanie Haridopolos is now serving as the acting leader while lawmakers consider Dr Nicole Saphier, a radiologist and former Fox News contributor.

“While screen use can have some benefits, the evidence of a range of risks to children’s overall mental and physical health is mounting,” the HHS secretary, Robert F Kennedy Jr, wrote in foreword to the advisory that comes with a motto “Live real life”.

Kennedy said that social media “is only one aspect of this ongoing screen time problem. Behavior patterns involving gaming, online gambling, and other forms of virtual interaction are emerging.”

He added that “screen time” is only an understood shorthand for “the entire digital ecosystem of apps, smartphones, tablets, chatbots, and other screen-associated devices and interfaces” and that the advisory was not simply a warning but “an invitation for all of us to enjoy a broader world, beyond the confines of screens”.

In a series of “calls to action”, the department recommended tracking screen time, taking breaks, creating a set of rules over screens and screen time, the implementation of restrictions by schools and monitoring by doctors. It also calls for researchers to study long-term impacts from screens and evaluate school cellphone policy bans.

The advisory comes hand-in-hand with a campaign by Melania Trump who launched a “Be Best” initiative in 2018 and focuses on issues affecting children, including social media and cyberbullying.