Sayings like “You’ll be fine after a good night’s sleep” and “Sleep on it” are widely used for good reason - there are lots of things happening in our brains while we sleep, so that we can function well the next day. Vhi clinical psychologist, Dr Aoife Dáibhis, explains why a good sleep pattern is so vital for teenagers’ mental health and how you can spot the signs your teen might not be getting enough sleep at night.

The role of sleep for mental health

We all know from experience that the day after a bad night’s sleep can really throw you for a loop. Your appetite feels off, you walk into rooms and forget what you came for, and minor inconveniences like getting your shirt caught on a door handle can feel like the last straw! But if you multiply one bad night’s sleep by many, so that it becomes a pattern, the impact is significant. Sleep is vital for our brain to repair and restore itself so that everything runs smoothly. While we sleep, we process information, consolidate our memories, and undergo what you could describe as ‘maintenance’ so that we function well during the day.

When we look at sleep and mental health for teenagers specifically, we can add a few more layers to the story! Teenagers need more sleep than adults do; the guidelines say 13 to 18 year olds need between 8-10 hours’ sleep a night. Aside from needing more sleep, teens also experience some changes to their internal clock once they hit adolescence. Children and adolescents who don’t get enough sleep are more at risk of developing mental health issues like poor emotional regulation, which means they can be more irritable, cranky or temperamental. Concentration and retention of information will also be affected by poor or lack of sleep, so your teen could struggle to focus during school as a result. Not getting enough sleep has clear impacts, but it’s not as straightforward as your teen choosing to sleep less at their age; the changes they experience during puberty play a big part.

Puberty and a change in circadian rhythm

Teens have a different sleep ‘schedule’ to children and adults. Once they hit puberty, a teenager’s internal clock (called the circadian rhythm, which regulates alertness and sleepiness) moves by one or two hours. This means that melatonin (a hormone that makes us sleepy) is released one or two hours later each night, so a teenager that used to sleep at 9pm now might not feel tired enough to sleep until 11pm. In turn, their bodies don’t want to wake up until two hours later each morning. Unfortunately, day-to-day schedules such as school start times don’t accommodate sleeping that extra hour or two in the morning. Your teen might find it difficult to sleep before midnight but still needs to get up at 7am each morning, putting them in a one to three-hour deficit. If your teen is consistently under the sleep target of 8-10 hours each night, it will start to impact various areas of their life, such as mood, appetite, and school. If this happens, you should check in with your healthcare provider for guidance. Working out a schedule with your teen and supporting them to stick to it will make all the difference for their sleep pattern.

Spotting the signs your teen isn’t getting enough sleep

You might see for yourself that your teen is going to bed quite late, or maybe they’ve told you they’re usually awake for a while after they get into bed. If that’s not the case, you’ll be able to tell they aren’t getting enough sleep by indicators such as:

• Lethargy or fatigue during the day
• Low energy
• Irritability or crankiness
• Poor memory or concentration
• Mood swings

Tips for improving sleep patterns

Although they have a changing internal body clock to compete with, teenagers can practice various habits, known as ‘sleep hygiene’, to try to improve their sleep cycle. They can try:

• Making sure their bedroom is at a comfortable temperature - not too hot or too cold.
• Following a largely consistent sleep and wake time each day.
• Ensuring their bedroom is quiet and dark.
• Reducing screen time in the couple of hours before sleep.
• No exercise right before sleep.

Once your teen finds what works for them, they should keep with that routine as consistently as possible. When it comes to the weekends, sleeping in a bit longer is fine as long as it doesn’t interrupt their sleep schedule once Sunday night comes round again. There’s no need to interfere if your teen is still asleep at 10am on a Saturday, but regularly spending much of the day in bed at the weekend is unhelpful and warrants a gentle knock on the bedroom door.

It’s possible for your teen to re-set their internal clock if it’s slipped into a bad pattern - especially during holidays from school. They’ll need to work at having a consistent wake time every day. Even if they fall asleep late the night before, the early wake time each day will eventually leave them sleepy earlier each night. Introducing ‘no tech’ rules is also effective for this; no phones or gaming after 9pm will help your teen to naturally unwind because their minds won’t be as active. It can be useful to negotiate these rules with your teen, so they feel less enforced, and more like a decision they were involved in. Maybe the no tech rule applies to the whole house, parents included. Or perhaps your teen can choose between ‘no tech after 8pm’ or ‘tech until 9pm but only in common spaces like the living room’.

‘Too much’ sleep

If your teen is consistently getting an excess of the recommended 8-10 hours’ sleep a night, this can potentially indicate mental health issues like low mood or depression. Every now and again, or one week of sleeping more than usual, is nothing to worry about. But if it’s for a prolonged period, it’s a good idea to speak to your healthcare provider. Excessive fatigue and sleepiness could also be a side effect of a physical illness, so it’s important to visit your healthcare provider for peace of mind. 

When your teen’s sleep is suffering due to stress about exams and school

This is a tough one and is also common. Firstly, have an open conversation and try to figure out if the stress crops up the night before an exam or if it’s felt over a longer period. Different solutions will work best depending on which of these your teen is dealing with. Maybe your teen is in an exam year, for example, and they have been stressed since the start of September. A predictable and consistent routine can be effective here, as is helping them find a good balance between exercise, sleep, study, and socialising. Teens who are particularly committed to their academics might need some extra support to achieve a balance, so they don’t burn themselves out or affect their sleep pattern and health. Work backwards with them on their schedule; first, figure out how many hours of sleep they need a night to make sure they feel well rested the following day (stick between the recommended 8 to 10 hours).  Next, agree on a set bedtime that ensures they’ll get enough sleep, and allow time to for them to unwind before sleeping. Choose a set slot of study time in the evenings, so time isn’t being borrowed from their window for relaxing and sleeping.

When your teen is more inclined to stress the night before an exam, support them and validate their feelings, and then find ways for them to de-stress. Maybe take them for a quick walk, try some breathing exercises, or watch an episode of their favourite show; whatever soothes them enough that they can unwind and sleep that night. You could also agree to get up a little earlier the morning of the exam and help them revise; this might reduce stress, so their sleep is less likely to be impacted. Simply work with them to bring your experience and expertise to the table and find a plan that works best for your teen.

This content is for information purposes only and is not intended or implied to be a substitute for professional medical advice, diagnosis, or treatment. Always seek advice from your GP or an appropriate medical professional if you have concerns about your health, or before commencing a new healthcare regime. If you believe that you are experiencing a medical emergency call 999 / 112 or seek emergency assistance immediately.

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