Home / Sleep News / Why Do Teens Need to Sleep So Much?

Why Do Teens Need to Sleep So Much?

Heather Turgeon
Julie Wright

Written by

Heather Turgeon and Julie Wright

Fact Checked Icon
Fact Checked

Our dedicated team rigorously evaluates every article, guide, and product to ensure the information is accurate and factual. Learn More

It’s no secret that preteens and teenagers want to sleep in. But logging hours of sleep well above and beyond the rest of the family on weekends still seems to leave many of them drowsy and wanting more. 

Psychotherapists and sleep specialists Heather Turgeon and Julie Wright witnessed this firsthand. And they wondered what they could do about it. 

In this passage from their new book, “Generation Sleepless: Why Tweens and Teens Aren’t Sleeping Enough and How We Can Help Them,” the authors examine the science of teen sleep and the challenge it may present parents, educators, and kids themselves in ensuring teens’ sleep needs are met.

Sleep Foundation staff

The Rumblings of an Approaching Storm

Middle childhood is the sunny springtime of sleep.

When kids are ages 6 to 10, the resistance to bedtime routines has often faded, nightmares are less frequent, and most school-age kids can go full speed all day long, running, swinging, reading, eating — and then naturally fall into a deep and long sleep. During this time, good sleep becomes the norm in many homes, and parents often forget it was ever a concern.

In adolescence, the pressure begins to build, and clouds of sleep loss move across the sky. This sweet honeymoon of sleep comes to an end.

In middle school, most kids lose their footing on healthy sleep habits. By age 15, the vast majority of kids are sleep-deprived.

A lab study of 10th graders showed that, when given the opportunity to sleep during the day, nearly half fell directly into REM sleep — a symptom normally associated with the sleep disorder narcolepsy. It took these kids an average of 3.4 minutes to fall asleep when given the chance at 8:30 a.m., a time when the average high schooler might be expected to take a calculus test. One set of data from the Centers for Disease Control and Prevention (CDC) showed that 57% of middle schoolers in the U.S. do not meet the recommended number of hours of sleep, and in high school that increased to 93%.

Meanwhile, the severity of the problem goes largely unnoticed. Many parents don’t realize how sleep-deprived their teen is and the nature of the mental and physical toll this takes on the body.

How Sleep Impacts Our Mood

Sleep is when growth hormone is secreted, muscles and tissues repair, and neural connections are refined and strengthened. Deep sleep sends soothing signals to the body’s fight-or-flight system. Healthy sleep gives us an infusion of neurochemicals like dopamine (the reward chemical) and norepinephrine (akin to the brain’s natural adrenaline), fueling us with positive energy. Our waking hours, on the other hand, are when stress hormones are higher and the body is taxed. When teens do not sleep enough, brain and body repair is cut short, positive neurochemicals are dampened, and the scales are tipped toward chronic stress. Regions of the brain, like the prefrontal cortex, that help us regulate emotions are dulled, which is why studies of even partially sleep-deprived people show they become more irritable, volatile, and negative.

Pioneering sleep researcher Dr. William Dement, known as the father of sleep medicine, once described sleep1 (or lack thereof) as creating our life’s mood music. When you sleep well, the background music is upbeat and positive, so you interpret people’s behaviors and daily events with humor and optimism. When you miss sleep, the mood music darkens, and suddenly people have questionable motives. Life takes on a more negative and gloomy tone.

To address teen mental health effectively is to address sleep. There’s just no getting around it.

Research closely connects lost sleep with deteriorating mental health. A recent study2 of adolescents in the U.K. found that teens who slept less at age 15 were significantly more likely to have symptoms of depression and anxiety at age 17 and in their early 20s. Those diagnosed with depression went to bed later, woke up more during the night, and were more likely to say they felt very sleepy during the day than those without a mental health diagnosis.

We are all discussing teen mental health, but sleep is a glaring hole in this conversation. To address teen mental health effectively is to address sleep. There’s just no getting around it.


The Dazzling Powers of Teenage Sleep

Do you remember, as a teen, that you could stay awake into the wee hours and sleep deeply through the morning — sunlight streaming in the windows, neighborhood dogs barking, and other family members banging pots and pans in the kitchen? Many teens have zero interest in climbing into bed before midnight and can sleep through a fire drill in the early morning.

What’s the reason for this teen nocturnal transformation? It’s not rebellion or laziness — as we once might have thought. The answer starts with an interesting shift in the adolescent sleep clock — a neurological change that sets teenagers on a later rhythm than the rest of us.

What we know about the curious sleep patterns of adolescents began to unfold in the 1970s, with the work of Dement and Mary Carskadon at Stanford University. To investigate how sleep changes through the preteen and adolescent years, the researchers created the Stanford Sleep Camp and embarked on a multiyear study.

Starting with a group of 10-, 11-, and 12-year-olds, the researchers organized camp-like activities during the day and measured the kids’ sleep at night. The same kids returned to campus in the summers for several years, giving a longitudinal view of how their sleep developed through adolescence.

What they expected was that kids would naturally sleep less as they got older. They were astounded to see this was not the case at all.

How Much Sleep Do Teens Need?

At the beginning of the study, the preteens slept an average of 9.25 hours of the 10 hours allotted. But every year they returned to sleep camp, they continued to sleep the same number of hours. Not only that: When they were younger, after nine or 10 hours of sleep, the kids tended to wake up naturally and easily and were alert when tested during the day. The older teenagers, on the other hand, despite also sleeping nine to 10 hours, often had to be woken up in the morning after an allotted 10-hour sleep period and were less alert during the day.

It was truly a surprise to see how much the older teens continued to sleep, and even with this long night of sleep, the data seemed to show they were drowsier than their younger counterparts.

Dement wrote that one of his first takeaways from the early years of the sleep camp was just how alert and well-rested the preteens were. He described them as “like puppies, bursting with energy; at night they slept about 10 hours” and referred to this age as the pinnacle of sleep perfection. Seeing that the older adolescents, by measures taken in the lab, were sleepier during the day initially led Carskadon and Dement to think that teens might need about an hour more sleep than younger kids. They later revised their thinking to reflect that the drowsiness resulted from the sleep debt these older teens carried (even though they were instructed to sleep for 10 hours a night the week before the lab assessments), as well as the developmental force we’ll explore in a moment — the natural timing shift in the teen sleep clock.

Regardless, the adolescents averaged about 9.25 hours at every age. Since these classic studies, much more research has backed up this need for an average of nine to 10 hours per night through adolescence.

Sleep Fuels the Teenage Brain

This remarkable desire for sleep has amazed scientists and parents alike. In lab studies, researchers have seen just how long teens’ bodies want to sleep, if given the chance. In a later study, Carskadon found that teenagers, studied in the lab for three nights, given an 18-hour opportunity to sleep, slept an average of nearly 12.5 hours the first night (again, a sign of teens making up for lack of sleep) and 10.1 hours by the third night.

Most parents tell us they too are in awe of their teen’s sleeping powers. A dad joked recently that over the summer, his two teenage boys were like cats — coming out to eat and then disappearing again, back to bed. night. If they’re allowed to sleep to their body’s full desire, many kids will sleep even more at age 16 than they did at age 10.

If this sounds surprising, consider how much sense it makes. As we have learned, the brain and body are going through massive transformations during adolescence, and much of this transformation in the brain happens during sleep. Remember when you worked so hard to get your baby sleeping on a schedule, or you noticed your toddler became hyper and overtired, so you created an elaborate bedtime routine to help with winding down? We take such good care of our little ones’ sleep because we know their brains are exploding with growth. Teenagehood is the same.

Changes related to puberty and a reorganization of the brain mean that the period of adolescence, similar to earlier massive developmental explosions, is a time when sleep becomes more important, not less. Meanwhile, recent estimates3 put the average teen at a loss of about two hours of sleep every school night.

If they’re allowed to sleep to their body’s full desire, many kids will sleep even more at age 16 than they did at age 10.

Sleep on the Decline

Even though teen sleep needs are high, their sleep time is at a historical low. The CDC’s Youth Risk Behavior Survey, a large, nationally representative sample of high schoolers, gathers data on sleep habits. The percentage of teens who sleep at least eight hours a night has been trending down for many years, with the most recent estimates around 20%.

This decline in sleep seems to be occurring at all ages. Data suggest children in general sleep an hour and a half less than they did in the 20th century. In the 1940s, Gallup poll data4 showed the average American adult slept just shy of eight hours per night. Now it’s 6.8.

As sleep researcher Robert Stickgold once told Harvard Magazine: “We are living in the middle of history’s greatest experiment in sleep deprivation, and we are all a part of that experiment.”

From the book GENERATION SLEEPLESS by Heather Turgeon MFT and Julie Wright MFT, published by TarcherPerigee, an imprint of Penguin Publishing Group, a division of Penguin Random House LLC. Copyright © 2022 by Heather Turgeon and Julie Wright.

  • Was this article helpful?
  • YesNo

About Our Editorial Team

Heather Turgeon

Guest Contributor

Heather Turgeon, MFT, is a psychotherapist, sleep specialist, and co-author of the popular parenting books "Generation Sleepless," "The Happy Sleeper," and "Now Say This." Through her online sleep classes and consultations as co-founder of The Happy Sleeper, she helps families with babies, kids, and teens sleep well. Heather’s writing has appeared in The New York Times and The Washington Post. She lives in Los Angeles and has a (well-rested) tween and teen.

Julie Wright

Guest Contributor

Julie Wright, MFT, is a psychotherapist, sleep specialist, and co-author of the popular parenting books "Generation Sleepless," "The Happy Sleeper," and "Now Say This." Through her online sleep classes and consultations as co-founder of The Happy Sleeper, she helps families with babies, kids, and teens sleep well. Julie is the creator of one of Los Angeles' best-known parenting programs, The Wright Mommy and Me. She lives in New York City and has a young adult son.


+4  Sources

Learn more about Sleep News