Most parents operate with a rough sense that screens are bad and that there's a recommended daily limit. That framing has been substantially revised by the bodies producing the guidance, and the revision hasn't propagated.
What changed
Earlier guidance tended towards specific time limits by age.
More recent guidance from several professional bodies has moved away from fixed limits for older children, on the grounds that the evidence doesn't support a specific threshold and that content and context matter more than duration.
The distinction now emphasised is between different kinds of screen use, and between screen time that displaces important activities and screen time that doesn't.
Some age-specific recommendations remain, particularly for very young children — guidance generally continues to advise against screen media for infants other than video calling, and limited use in the toddler years.
Why the shift
Several reasons.
The evidence was weaker than assumed. Reviews examining associations between screen time and child outcomes have found small effect sizes and substantial methodological limitations, including reliance on self-reported time and difficulty separating screen use from confounding factors.
Some prominent analyses have found that associations between screen time and wellbeing, while statistically detectable in large samples, are small in magnitude — comparable to other everyday factors that nobody worries about.
"Screen time" isn't one thing. A video call with a grandparent, a maths game, a documentary, a video platform's autoplay feed and a social media app have essentially nothing in common except the device. Aggregating them produces a measure of limited meaning.
Displacement is the plausible mechanism. Where harm is found, the more likely explanation is what the screen use replaced — sleep, physical activity, face-to-face interaction, reading — rather than something inherent to screens.
Which suggests protecting those activities is more useful than counting hours.
The current framing
Guidance now tends to focus on questions rather than limits.
Is screen use displacing sleep? Sleep is where the evidence for harm is strongest, and devices in bedrooms at night are the clearest issue.
Is it displacing physical activity?
Is it displacing interaction with people?
Is the content appropriate and, ideally, of some quality?
Is use shared or solitary? Co-viewing, with an adult talking about what's on screen, appears to change what children get from it, particularly for younger ones.
Are there device-free times and places — meals, bedrooms, the hour before sleep?
Those questions produce more useful answers than a stopwatch.
The very young
Where guidance remains more restrictive, and for a specific reason.
Young children learn substantially less from screen content than from equivalent live interaction — a well-documented finding sometimes described as the video deficit. Below roughly two and a half, transfer of learning from video to real situations is poor.
Video calling appears to be an exception, plausibly because it's interactive and contingent — the person on screen responds to the child.
The practical implication is that screen media for infants and young toddlers isn't harmful so much as ineffective, and time spent that way is time not spent on interaction that would teach more.
The bigger issue
An argument gaining ground: the focus on total time has distracted from questions about specific designs.
Recommendation algorithms optimised for engagement, autoplay, infinite scroll, variable reward mechanics and social comparison features are not equivalent to other screen uses, and the concerns about them are more specific and arguably better founded than concerns about screens generally.
Which suggests attention should be on what a child is using rather than for how long — and that a household rule about which applications are available may matter more than one about minutes.
Practical suggestions
What seems well supported.
Protect sleep absolutely. No devices in bedrooms overnight. This is the single clearest recommendation and the one with the best evidence behind it.
Device-free meals. Preserves interaction and is easy to implement consistently.
Co-view where practical, particularly with younger children.
Know what they're using, not just how long.
Model it. Children's device use correlates with their parents'. Rules that don't apply to adults are read accurately as rules about power rather than about wellbeing.
Talk about it rather than only restricting. Particularly with older children, where the goal is developing their own judgement rather than external control that ends when they leave home.
General information only. Guidance varies between countries and is periodically updated; check current advice from your national health authority.
Content quality, briefly
Since the guidance now emphasises content over duration, it is worth saying what distinguishes better content for younger children.
Slower pacing. Research comparing fast-paced and slower programming has found short-term effects on executive function measures immediately afterwards, favouring the slower material.
Clear narrative rather than rapid disconnected segments. Language that models full sentences. Content that invites response rather than only delivering stimulation.
And ideally something you can talk about afterwards, since the conversation is where a good deal of the value sits for younger children.