Posted: Jun 25, 2014 7:00 AM
Anyone with teens knows — if they could sleep past noon every day, they would do it. Why do they need so much sleep and how do they sleep so long?
Photo credit: Juanmonino/ E+/ Getty Images

Teenagers are capable of staying awake until the wee hours of the morning to cram for finals, then have no problem tuning out the vacuum cleaner and chaos of the house in order to sleep until noon. The phrase "sleep like a baby" might actually be more accurate as "sleep like a teen." Researchers are interested in teens and their sleep habits — and we wanted to learn more.

What does sleep really do for us, anyway?

For those of us (me) who don't often feel there are enough hours in the day to get all the things accomplished, sleep can feel like a waste of time. So why sleep? University of California Berkeley researchers Matthew Walker, who directs the sleep and neuroimaging laboratory, and Allison Harvey, who leads the sleep and psychological disorders laboratory have found that sleep doesn't just refresh our bodies and give our brain a reboot. The amount of sleep we get has a direct effect on how our memory functions, our immune system responses, our metabolism, control of our emotional functioning and even learning. Sounds like we all need more sleep then, right?

But our need for sleep isn't only measured in hours but in quality as well, which is often affected by nighttime routines. Teens are often doing multiple things at the same time — texting with friends, downloading a new song, working on homework or studying for a test — right up until the time they try to fall asleep. So while our teens need even more sleep than we adults need, their habits and tendency to stay up later don't always help them get the sleep they need.

Why teens need their sleep

Parents spend a lot of time enforcing sleep habits and bedtime routines with our babies and elementary-aged children, but that isn't the case by the time they are teens. "At some point between childhood and the teenage years, parents stop worrying about sleep and start worrying about everything but sleep, including homework and sports," says Walker. Many experts say that nine hours of sleep is a good target for teens, who are experiencing an incredible period of growth during this time.

The hormones of puberty are thought to have an impact on bedtimes and waking times, pushing both later as teens pass through their high school years. These effects then begin to reverse by the early 20s, which is why a father in his 50s might wake up a good two hours earlier than his teen. "During adolescence, surges of hormones have an amphetamine type effect on the pineal gland of the brain, a tiny, little pea-sized gland that produces melatonin and causes you to be drowsy," shares JoAnne Deak, Ph.D., author and psychologist. "As you move into adolescence with these surges of hormones, the pineal gland is actually suppressed for a couple of hours." This explains why teens have a hard time falling into a good sleep until 11 p.m. or even later. With many school bells ringing at 8 a.m. or earlier, it's easy to see how teen sleep deficits add up quickly.

Inadequate sleep can result in academic underachievement, health-damaging behaviors and negative mood.

Skimping on sleep not healthy

Researcher Karen Matthews, professor of psychiatry at the University of Pittsburgh School of Medicine, studied 250 high school students and found that they were averaging about six hours of sleep per night, which is only 66 percent of the recommended nine hours teens need. She noted in her report, which was published online in the journal Pediatrics, that the teens who skimped on sleep most often reported that they drink alcohol, use marijuana, smoke and experience mental health issues such as feeling hopeless. "Inadequate sleep can result in academic underachievement, health-damaging behaviors and negative mood," Matthews says. Earlier research tied insufficient sleep to serious health concerns, such as higher blood pressure and insulin resistance, which is a risk factor for diabetes.

Better health, better grades?

In addition to the impact that getting enough sleep has on your teen's overall health and mental well-being, there may be an impact on his studies as well. Sleep plays a big role in learning and memory, and was the focus of Walker's main studies. His studies show that our past experiences, as well as facts we have learned, are more easily accessed when we have had a good enough amount of sleep. Walker says that while we sleep, fragile new memories must pass through our brain's neural architecture before being stored for later retrieval. Those Revolutionary War facts your teen was cramming before bedtime? They are becoming memories while she sleeps.

Bottom line^Don't boot those teens from the bed. Help them get the sleep they need while their bodies and brains are still growing.

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