Sleep

The teen body clock

Teenagers' body clocks naturally shift later, yet they still need 8 to 10 hours of sleep. Learn why, and how to protect your sleep around school, coaching and phones.

5 minutes·For 14 to 16, 17 to 19

Why teens feel awake at night

During puberty, your body clock shifts. The sleep hormone melatonin is released later in the evening, so you may not feel sleepy until later at night.

But school, coaching and tuition often start early. This mismatch leaves many teenagers short of sleep.

How much sleep you need

Teenagers aged 13 to 18 need about 8 to 10 hours of sleep a night.

Signs you are short of sleep: struggling to wake up, dozing in class, needing caffeine to get through the day, irritability, poor concentration and sleeping very late at weekends.

Too little sleep is linked to lower marks, more accidents, low mood, getting ill more often and feeling hungrier for sugary foods.

Phones and sleep

Screens give off light that delays melatonin, and exciting content keeps the brain alert. Notifications can wake you in the night.

Try charging your phone outside your bedroom, or at least across the room, with notifications off. Stop scrolling about an hour before bed.

Better sleep habits

Keep a regular wake-up time, even on weekends, to anchor your body clock. Get daylight in the morning.

Avoid tea, coffee, cola and energy drinks in the afternoon and evening.

Keep your room dark, cool and quiet. If you share a room, an eye mask or earplugs can help.

A short nap after school, under about 30 minutes, can help. Long late naps make night sleep harder.

Key points

Teen body clocks naturally shift later.
Teens need about 8 to 10 hours of sleep.
Screens before bed delay sleep.
A regular wake-up time and morning light help reset your clock.
Avoid caffeine later in the day.

Myth or fact?

Myth

Teenagers who sleep late are lazy.

Fact

Teen body clocks really do shift later. It is biology, not laziness.

Myth

You can train yourself to need only five hours of sleep.

Fact

Almost no one can. Your body still needs 8 to 10 hours, even if you get used to feeling tired.

When to get help

See a doctor if you regularly cannot fall asleep or stay asleep, or feel exhausted despite enough sleep.
See a doctor if you snore loudly, stop breathing during sleep, or fall asleep suddenly during the day.
If worry or low mood keeps you awake, talk to someone, or call Tele-MANAS on 14416.

Get help now

Check what you know

1.Why do teenagers often feel sleepy later at night?

2.How much sleep do most teenagers need?

3.What helps reset your body clock?

Based on guidance from American Academy of Pediatrics, WHO, NHS. Awaiting review by Puberty Lab's clinical advisory board. General education, not medical advice for any one person.