Sleep Expert Shares The Science Behind Why Teens Are Such Night Owls

After years of sleep deprivation and the general chaos of life, parents have become pretty proficient at hunkering down for an early night.

But this is often at odds with the schedule of their teenage children, who are all for those late nights and, as a result, late morning lie-ins. 

Dr Sophie Bostock, resident sleep expert for Bensons for Beds, says there’s actually an easy explanation behind teenagers’ unusual sleeping patterns. And it’s all down to science. 

“In the evening, the sleep hormone melatonin signals the brain and body to prepare for sleep,” she says.

Adults usually start to produce melatonin before 9pm, around 90 minutes before the onset of sleep, she explains, whereas the average teen’s melatonin production starts hours later.

For pretty much all teens, the release of melatonin doesn’t begin until about 10.45pm and lasts until 8am – this means most will be unable to fall asleep until this process begins, and it’ll be pretty difficult for them to wake up early too.

So, Dr Bostock adds, expecting a teenager to go to bed at 10pm is a bit like asking an adult to be in bed at 8pm – they’re just not that sleepy.

In addition to our body clocks, a second drive to sleep comes from the build up of a drowsy-inducing chemical called adenosine.

The longer we’ve been awake, the greater the sleepiness we feel from adenosine – this is also called sleep pressure.

“Sleep pressure accumulates in teens more slowly than in adults, which is another reason they feel sleepy later than their parents,” says Dr Bostock. 

Delays to the body clock typically appear around the onset of puberty, when there are surges in sex hormones.

For girls in particular, puberty can also be accompanied by difficulties falling asleep and waking up during the night, says the expert.

“Fluctuations in oestrogen and progesterone can have an unsettling impact on sleep,” she explains.

“Girls who experience pre-menstrual syndrome (PMS) often report insomnia symptoms, disturbed dreams or excessive sleepiness during the day.”

A survey from Bensons for Beds revealed that environmental factors can also disrupt teen sleep. It found discomfort, room temperature and a lack of bedtime routine can all play a part.

And, shock horror, social media use can have a knock-on effect on bedtime, too. 

A recent study by the BMJ, analysing 11,872 teens aged 13-15, found extreme social media users were roughly 70% more likely to fall asleep after 11pm on school days and after midnight on free days than average social media users.

Whilst science is a force to be reckoned with, Dr Bostock has shared some helpful advice for those wanting to support their teenagers’ sleep:

• Stick to the same wake up and wind down schedule as often as possible, even on weekends.
• Aim for a minimum of 8.5 hours in bed, every night. Younger teens are likely to need more than this.
• Spend at least 15 minutes outside in daylight, or with a bright SAD lamp, in the first hour after waking.
• Get active every day – this might just mean going for a walk, or doing some gentle stretching.
• Avoid caffeine in the afternoon and evening.
• Dim bright lights and limit exposure to screens (or use night mode) in the last 90 minutes before bed. Leave screens outside the bedroom.
• Try to eat something within the first two hours of waking up, and avoid eating large meals or very sugary snacks in the last two hours before getting into bed.
• Design a consistent bedtime routine for the last 30-60 minutes before bed. Relaxing rituals can help to prepare the body for a deep sleep. For example, journalling, reading a book, crafts, listening to music, meditating or having a warm bath.