When your child can't sleep: anxiety, screens and the teenage body clock

A child who can't switch off at night is tired and on edge the next day, and a child who is on edge struggles to switch off. Each keeps the other going. The research is fairly clear about which usually comes first in teenagers, and that's useful, because it points to something a family can change.

Sleep and worry feed each other

Poor sleep and anxiety each make the other more likely. A review of long-term studies across all ages suggested this can work both ways round: insomnia went with later anxiety and depression, and anxiety and depression with later insomnia, though the authors said firm conclusions were not yet possible. In the studies of children, poor sleep came before low mood but not the other way round ^[1].

The effects can also last a long time. A large UK study followed more than 5,000 young people and found that those who slept badly at 15 were more likely to be anxious or low at 17, at 21 and even at 24 ^[2]. It also found that anxious teenagers mostly described sleep that didn't feel restful, rather than problems with when they went to bed.

So when an anxious child says they’re sleeping badly, they often mean the sleep they get isn't restful: lying awake, waking in the night, never quite feeling rested. Bedtime itself may look normal.

Which comes first?

For teenagers, the research leans one way. One study followed young people for fifteen years and looked at what happened to each of them over time. When a young person went through a spell of poor sleep, more anxiety tended to follow. It didn't reliably work the other way round: a spell of anxiety wasn't usually followed by worse sleep ^[3].

The effect was modest, so it isn't a hard and fast rule. But it does mean sleep deserves attention in its own right, rather than being treated as a symptom that will sort itself out once the anxiety lifts.

Lying awake going over things

Part of the link is something most parents will recognise: the mind that won't switch off.

A study that followed 11 to 16 year olds for five years found that those who slept poorly went on to become more anxious and low. Part of the reason was worrying: going over the same thoughts again and again, including the worry that arrives at bedtime ^[4]. Here too, it didn't work the other way round: being anxious or low didn't lead to worse sleep later.

In practice this looks like a young person replaying something awkward that happened at school, dreading a test or a social situation tomorrow, or running over the same thought again and again. The dark and the quiet leave nothing else to think about. The less they sleep, the harder it is to hold those thoughts at bay the next night.

If your child's worry is showing up in the daytime too, our guide to anxiety covers the wider picture.

The teenage body clock

There is also a biological reason teenagers stay up late. At puberty, the body clock shifts later, so many teenagers genuinely don't feel sleepy until late in the evening, while school still starts early. That mismatch is covered in our guide to why a child can seem unmotivated, including how much sleep teenagers need.

The body clock explains why a teenager goes to bed late. It doesn't explain lying awake worrying, which is why it helps to keep the two apart.

What the evidence actually says about screens

Screens get most of the blame for teenage sleep, and the advice parents usually hear is to stop all screens an hour before bed. The best recent evidence is narrower than that, and kinder.

One study filmed what young teenagers were actually doing on their screens before bed and measured their sleep with wrist monitors. Screen use in the two hours before bed made little difference to most measures of their sleep. What did matter was using a screen once in bed, especially for something interactive like gaming, and doing several things at once ^[5]. It was a small study, but a 2026 review of 25 studies found much the same: screens pushed bedtime a little later, but made little difference to how long or how well young people slept ^[6].

Other studies point the same way: what a young person is doing on the screen, and where, matters more than the screen itself. Teenagers who messaged friends or gamed in the hour before bed fell asleep around half an hour later than those who didn't, while quieter use, such as watching videos, may not affect sleep ^[7]. In a London study of 11 and 12 year olds, using a phone in a dark room before sleep was linked to too little sleep on school nights ^[8].

So the useful line isn't "no screens after tea", which tends to become a nightly argument. It's that the phone comes out of bed, notifications go off overnight, and the gaming and group chats finish before lights out. A teenager watching something quietly before bed is a much smaller concern than one who takes their phone under the covers.

What helps

Work on sleep in its own right

The encouraging part is that helping sleep also helps anxiety. A large 2026 review, which included trials, found that when young people's sleep improved, their anxiety eased, and when their sleep was cut short, their anxiety rose ^[9]. So sleep isn't only a sign that something is wrong. It can also be a practical place to start when you're trying to reduce anxiety.

Keep the wake time steady

A consistent time to get up, including at weekends, does more to set the body clock than a fixed bedtime. Long weekend lie-ins can make Sunday night and Monday morning harder.

The phone charges outside the bedroom

This targets the kind of screen use that matters most: the late-night messaging, the scrolling under the covers and the notifications in the night, without banning screens in the evening. Even a fairly late cut-off can help. In one study, teenagers asked to stop using screens after 9pm on school nights fell asleep earlier, slept longer and were more alert the next day ^[10].

It works best as a family arrangement rather than a punishment, and better still if the adults' phones charge downstairs too.

Move the worry earlier

If bedtime is when the worrying starts, it helps to give it somewhere to go earlier in the evening. That might be ten minutes of talking in the car, over food, or doing the washing up. Some young people find it helps to write down what's on their mind before bed, so it isn't all waiting for them in the dark.

Don't make sleep a battleground

Sleep cannot be forced, and pressure to fall asleep can add to the worry that is keeping a child awake. Calm, consistent routines tend to work better than nightly negotiations.

Talking to your child about sleep

Most of the changes above work better when a young person has helped to shape them. A plan agreed together is more likely to stick than one announced at bedtime.

Pick a calm moment

Bedtime, when everyone is tired, is the hardest time to talk about sleep. A weekend afternoon or a car journey tends to go better. Starting with what you've noticed, rather than what needs to change, keeps it from feeling like a telling off: "You've seemed really tired in the mornings lately. How are you sleeping?"

Ask what's keeping them awake

A young person who can't sleep often knows more about why than anyone else. It might be a group chat that runs late, a falling out with a friend, a test coming up, or simply not feeling tired. Asking, and listening to the answer before offering solutions, shows which kind of help will make a difference. It also lets them know the worries that come up at night are something they can bring to you during the day.

Explain the why, not just the rule

Many young people don't know that the body clock shifts later in the teenage years, or that screens in bed matter more than screens in the evening. Sharing what the research says can make a phone rule feel less like a punishment and more like common sense. Some teenagers are more open to a change once they see it's about how sleep works, not about control.

Agree the plan, and keep a few limits

Give them a say in the details, such as when and where the phone charges and what happens at weekends. That makes the plan theirs as well as yours. Limits still help, though. In an Australian study, teenagers with a parent-set bedtime on school nights went to bed earlier, slept longer and felt less tired during the day ^[11].

Keep checking in

Sleep habits drift, especially around exams, holidays and the start of a new school year. A quick, relaxed check-in every few weeks ("How's the phone-downstairs thing going?") keeps the plan working without turning it into a nightly argument.

When to talk to the GP

Most sleep problems settle with steady routines and patience. If you're worried, that is reason enough to speak to your GP, especially if:

• sleep problems seem to be settling in rather than passing, despite changes at home
• they're affecting school, mood or how your child copes during the day
• your child is very sleepy during the day, or snores loudly and seems to stop breathing at night
• poor sleep comes alongside low mood, panic attacks or a lot of worry

Our guide to when to speak to the GP about your child's mental health covers how to have that conversation. If your child is having panic attacks at night, our guide to panic attacks may also help.

When worry is what keeps a young person awake, counselling can help with the worry itself. At Finding Therapy, you can browse our counsellors and choose someone for your child yourself. We've vetted every one of them, and we've known them for years.

If you'd like help choosing, you can book a free consultation with Helen Spiers, our Head of Counselling. We work with children and young people aged 6 to 25. We're a private, paid service with no GP referral needed, and a first session can be available in as little as 48 hours.