"Do not let them watch screens" is advice you hear constantly, but how many hours actually counts as the limit is rarely set out clearly. In 2019 the World Health Organization published guidelines on physical activity, sedentary behaviour and sleep for children under five, and they contain specific numbers. Let us look at the numbers first, then at how to apply them in real life.

What the numbers mean — a ceiling, not a target

The 60 minutes for two- to four-year-olds is an upper limit, not a recommended amount. The WHO adds the phrase "less is better". In other words, it is not a quota to fill but a line not to cross.

For children under one, screen exposure is not recommended at all. What a child needs at that age is not a screen but back-and-forth interaction with people.

Another point that is easy to miss is that the WHO guidelines do not deal with screen time alone. Recommendations for physical activity and sleep are given alongside it. Screen time is a problem less in itself than because it pushes out time spent moving and time spent sleeping. Seen as a question of how the whole day is divided up, the judgement becomes easier.

The bigger variable: alone, or together

The same 30 minutes can be two different things. Thirty minutes of a child staring at a screen alone and 30 minutes with an adult beside them talking about what is on it do not give the child the same thing.

What you can do while watching together is simple.

• Name what is on screen. "The dog is running."
• Take up the child's reaction in words. When they point, turn it into a sentence.
• Talk about it afterwards. Even briefly.

Do that and the screen turns from one-way stimulation into material for conversation. The sheer amount of language input changes.

Realistic ways to cut it down

Knowing the limit and keeping to it are two different things. There are moments when a screen is the only option because someone has to cook dinner or simply catch their breath. There is no need to blame yourself for not keeping to it perfectly. It is more realistic to start with the time that is easiest to remove.

• Do not leave it on in the background. A screen that is on while nobody is watching is the easiest time to reclaim.
• Turn it off at mealtimes. Conversation over food is language input that is hard to replace.
• Avoid the hour before bed. It has a direct bearing on meeting the sleep recommendations.
• Agree the end point in advance. "When this one finishes, we turn it off" — settling the stopping condition first cuts down the arguing.
• Have the next activity ready. Switching it off leaves a gap. It is better to have something to put in their hands.

If development worries you, do not start by counting hours

If speech is late or interaction is limited even after screen time has come down, it is better not to try to explain it by exposure alone. Language delay has many causes, and there is already a route for checking it through the developmental screening in the national infant health check-up. That process is set out in Early Development.

In summary

The numbers to remember are not recommended under one, no more than 60 minutes a day at two to four, three hours of physical activity at three to four, and 10 to 14 hours of sleep. And changing how you watch — together, talking — makes more difference in practice than shaving minutes off.