TallPlanHow much sleep, by age
The American Academy of Sleep Medicine’s recommendations, also endorsed by the American Academy of Pediatrics, count hours of sleep in every 24:
| Age | Hours of sleep a day |
|---|---|
| 6 to 12 | 9 to 12 |
| 13 to 18 | 8 to 10 |
The low end is the minimum, not the goal. A 15-year-old who sleeps 8 hours on school nights is at the floor; many feel better closer to 9.
What sleep has to do with growing
Growth hormone is released in pulses, and the biggest ones come during deep sleep, mostly in the first part of the night. That is the real link between sleep and height: a large share of growth hormone is released while you sleep.
What sleep can’t do is add height beyond what your genes and health allow, and more sleep than you need won’t make you taller. The aim is simply enough sleep, most nights. It supports the body’s normal daily rhythms, growth hormone included, and it clearly helps mood, concentration at school and recovery from sport.
Why it is hard for teens
During puberty the body clock shifts later. Teens tend to feel sleepy later at night than they did as kids, while school still starts early. That squeeze is why so many teens run short on weekdays and try to catch up at weekends.
Working out your bedtime
Count back from the time you have to get up:
Wake-up time − hours of sleep you need − about 15 minutes to fall asleep = time to be in bed
Up at 07:00, aiming for 8.5 hours: in bed by 22:15.
TallPlan works out tonight’s “in bed by” time for you, from the target for your age and the time you usually wake up.
Habits that make it easier
- Keep the same times on weekends, or within an hour or two. Long weekend lie-ins push the body clock later and make Monday harder.
- Dim the lights in the last hour, and put the phone away from the bed. Bright screens late at night delay sleepiness.
- Watch caffeine after lunch. Cola, energy drinks, coffee and some teas can keep you awake hours later.
- Get daylight in the morning. Light soon after waking helps set the body clock earlier.
- Keep naps short and before mid-afternoon, so they don’t eat into the night.
When to see a doctor
If sleep is a struggle that habits don’t fix, it’s worth asking a doctor. Some common reasons:
- Loud snoring, pauses in breathing or gasping in sleep.
- Trouble falling or staying asleep most nights for weeks, even with good habits.
- Falling asleep in class or feeling exhausted despite enough hours in bed.
Sources
- Paruthi S, et al. Recommended amount of sleep for pediatric populations: a consensus statement of the American Academy of Sleep Medicine. Journal of Clinical Sleep Medicine, 2016.
- American Academy of Sleep Medicine. AAP publishes endorsement of AASM pediatric sleep duration recommendations, 2016.
- Van Cauter E, Plat L, Copinschi G. Interrelations between sleep and the somatotropic axis. Sleep, 1998.
- American Academy of Pediatrics, HealthyChildren.org. My teen is having trouble falling asleep at night. How can I help?
- American Academy of Pediatrics, HealthyChildren.org. Daylight saving time: don’t lose sleep over it.
- Misiunaite I, Eastman CI, Crowley SJ. Circadian phase advances in response to weekend morning light in adolescents with short sleep and late bedtimes on school nights. Frontiers in Neuroscience, 2020.
