Garrett had a hard time waking up for school during his sophomore year. At first he thought it was because he'd been going to bed late over summer vacation and then sleeping in the next day. He assumed he'd adjust to his school schedule after a couple of weeks. But as the school year progressed, Garrett found himself lying awake in bed until 2 or 3 in the morning, even though he got up at 6:30 AM every day. He began falling asleep in class and his grades started to suffer.
Most teens don't get enough sleep, but that's usually because they're overloaded and tend to skimp on sleep. But sleep problems can keep some teens awake at night even when they want to sleep.
Over time, those nights of missed sleep (whether they're caused by a sleep disorder or simply not scheduling enough time for the necessary ZZZs) can build into a sleep deficit. People with a sleep deficit are unable to concentrate, study, and work effectively. They can also experience emotional problems, like depression.
What Happens During Sleep?
You don't notice it, of course, but while you're asleep, your brain is still active. As people sleep, their brains pass through five stages of sleep. Together, stages 1, 2, 3, 4, and REM (rapid eye movement) sleep make up a sleep cycle. One complete sleep cycle lasts about 90 to 100 minutes. So during an average night's sleep, a person will experience about four or five cycles of sleep.
Stages 1 and 2 are periods of light sleep from which a person can easily be awakened. During these stages, eye movements slow down and eventually stop, heart and breathing rates slow down, and body temperature decreases. Stages 3 and 4 are deep sleep stages. It's more difficult to awaken someone during these stages, and when awakened, a person will often feel groggy and disoriented for a few minutes. Stages 3 and 4 are the most refreshing of the sleep stages — it is this type of sleep that we crave when we are very tired.
The final stage of the sleep cycle is known as REM sleep because of the rapid eye movements that occur during this stage. During REM sleep, other physical changes take place — breathing becomes rapid, the heart beats faster, and the limb muscles don't move. This is the stage of sleep when a person has the most vivid dreams.
Why Do Teens Have Trouble Sleeping?
Research shows that teens need 81/2 to more than 9 hours of sleep a night. You don't need to be a math whiz to figure out that if you wake up for school at 6:00 AM, you'd have to go to bed at 9:00 PM to reach the 9-hour mark. Studies have found that many teens have trouble falling asleep that early, though. It's not because they don't want to sleep. It's because their brains naturally work on later schedules and aren't ready for bed.
During adolescence, the body's circadian rhythm (sort of like an internal biological clock) is reset, telling a teen to fall asleep later at night and wake up later in the morning. This change in the circadian rhythm seems to be due to the fact that the brain hormone melatonin is produced later at night in teens than it is for kids and adults, making it harder for teens to fall asleep. Sometimes this delay in the sleep–wake cycle is so severe that it affects a person's daily functioning. In those cases it's called delayed sleep phase syndrome.
Changes in the body clock aren't the only reason teens lose sleep, though. Lots of people have insomnia — trouble falling or staying asleep. The most common cause of insomnia is stress. But all sorts of things can lead to insomnia, including physical discomfort (the stuffy nose of a cold or the pain of a headache, for example), emotional troubles (like family problems or relationship difficulties), and even an uncomfortable sleeping environment (a room that's too hot, cold, or noisy).
It's common for everyone to have insomnia from time to time. But if insomnia lasts for a month or longer with no relief, then doctors consider it chronic. Chronic insomnia can be caused by a number of different problems, including medical conditions, mental-health problems, medication side effects, or substance abuse. People with chronic insomnia can often get help for their condition from a doctor, therapist, or other counselor.
For some people, insomnia can be made worse by worrying about the insomnia itself. A brief period of insomnia can build into something longer lasting when a person becomes anxious about not sleeping or worried about feeling tired the next day. Doctors call this psychophysiologic insomnia.
Periodic Limb Movement Disorder and Restless Legs Syndrome
People with these conditions find their sleep is disrupted by leg (or, less frequently, arm) movements, leaving them tired or irritable from lack of sleep. In the case of periodic limb movement disorder (PLMD), these movements are involuntary twitches or jerks: They're called involuntary because the person isn't consciously controlling them and is often unaware of the movement.
People with restless legs syndrome (RLS) actually feel physical sensations in their limbs, such as tingling, itching, cramping, or burning. The only way they can relieve these feelings is by moving their legs or arms to get rid of the discomfort.
Doctors can treat PLMD and RLS. For some people, treating an iron deficiency can make them go away; other people may need to take other types of medication.
Obstructive Sleep Apnea
A person with this sleep disorder temporarily stops breathing during sleep because the airway becomes narrowed or blocked. One common cause of obstructive sleep apnea is enlarged tonsils or adenoids (tissues located in the passage that connects the nose and throat). Being overweight or obese can also lead a person to develop obstructive sleep apnea.
People with obstructive sleep apnea may snore, have difficulty breathing, and even sweat heavily during sleep. Because it disrupts sleep, someone with sleep apnea may feel extremely sleepy or irritable during the day. People who show signs of obstructive sleep apnea, such as loud snoring or excessive daytime sleepiness, should be evaluated by a doctor.
If someone has gastroesophageal reflux disease (GERD), stomach acid moves backward up into the esophagus, producing the uncomfortable, burning sensation known as heartburn. GERD symptoms can be worse when someone is lying down. Even if someone doesn't notice the feelings of heartburn during sleep, the discomfort it causes can still interfere with the sleep cycle.
Most teens have nightmares on occasion. But frequent nightmares can disrupt sleep patterns by waking someone during the night. Some things can trigger more frequent nightmares, including certain medications, drugs, or alcohol. Ironically, sleep deprivation can also be a cause.
The most common triggers for more frequent nightmares are emotional, such as stress or anxiety. If nightmares are interfering with your sleep, it's a good idea to talk to a parent, doctor, or counselor.
People with narcolepsy are often very sleepy during the day and have sleep "attacks" that may make them suddenly fall asleep, lose muscle control, or see vivid dreamlike images while dozing off or waking up. Someone's nighttime sleep may be disrupted, with frequent awakenings throughout the night.
Narcolepsy can be disturbing because people fall asleep without warning, making it hazardous to do things like drive. A person's schooling, work, or social life can be affected by the unusual sleep patterns.
Narcolepsy is not that commonly diagnosed in teens, although many cases go unrecognized. People usually first begin to have symptoms between the ages of 10 and 25, but may not be properly diagnosed until 10–15 years later. Doctors usually treat narcolepsy with medications and lifestyle changes.
It's rare for teens to walk in their sleep; most sleepwalkers are children. Sleepwalking may run in families. It tends to happen most often when a person is sick, has a fever, is not getting enough sleep, or is feeling stress.
Because most sleepwalkers don't sleepwalk often, it's not usually a serious problem. Sleepwalkers tend to go back to bed on their own and don't usually remember sleepwalking. (Sleepwalking often happens during the deeper sleep that takes place during stages 3 and 4 of the sleep cycle.)
Sometimes, though, a sleepwalker will need help moving around obstacles and getting back to bed. It's also true that waking sleepwalkers can startle them (but it isn't harmful), so try to guide a sleepwalker back to bed gently.
What Should I Do?
If you think you're getting enough rest at night and you're still feeling tired during the day, it's a good idea to visit your doctor. Excessive tiredness can be caused by all sorts of health problems, not just difficulties with sleep.
If a sleep problem is suspected, your doctor will look at your overall health and sleep habits. In addition to doing a physical examination, the doctor will take your medical history by asking you about any concerns and symptoms you have, your past health, your family's health, any medications you're taking, any allergies you may have, and other issues. The doctor also might do tests to find out whether any conditions — such as obstructive sleep apnea — might be interfering with your sleep.
Different sleep problems are treated differently. Some can be treated with medications, whereas others can be helped by special techniques like light therapy (where someone sits in front of a lightbox for a certain amount of time each day) or other practices that can help reset a person's body clock.
Doctors also encourage teens to make lifestyle changes that promote good sleeping habits. You probably know that caffeine can keep you awake, but many teens don't realize that playing video games or watching TV before sleeping can do the same thing.
Reviewed by: Mary L. Gavin, MD
Date reviewed: January 2011
Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.
© 1995-2015 The Nemours Foundation/KidsHealth. All rights reserved.