Skip Navigation Bar
NIH MedlinePlus the Magazine, Trusted Health Information from the National Institutes of Health

Your Wake-Up Call

A man taking a sleep study.


Researchers at NIH's National Center on Sleep Disorders Research are discovering the many ways that skimping on sleep can be harmful to your health.

When you're trying to squeeze in more time for your work, family, and other activities, it can seem like your only option is to cut back on sleep. But that could be a dangerous choice. Sleep isn't just "down time," when your brain shuts off and your body rests.

"We are learning more and more about how sleep disturbances can increase the risk of many health problems, including hypertension, cardiovascular disease, diabetes, obesity, and infections," says Michael Twery, Ph.D., Director of the National Heart, Lung, and Blood Institute's National Center on Sleep Disorders Research (NCSDR).

The NCSDR was established in 1993 to combat a serious public health concern. About 70 million Americans suffer from sleep problems; among them, nearly 60 percent have a chronic disorder. Each year, sleep disorders, sleep deprivation, and sleepiness add an estimated $15.9 billion to the national health care bill. Additional costs to society for related health problems, lost worker productivity, and accidents have not been calculated. Sleep disorders and disturbances of sleep comprise a broad range of problems, including sleep apnea, narcolepsy, insomnia, parasomnia, jet-lag syndrome, and disturbed biological and circadian rhythms. The NCSDR conducts and funds research relating to all sleep disorders.

participant Scott Ward

At a SleepMed diagnosis and therapy center in Maryland, participant Scott Ward prepares to have his own sleep patterns and possible problems diagnosed.

Why Sleep Is Important

Adults, even seniors, need at least 7 to 8 hours of sleep a night, NCSDR research shows. Not getting enough sleep has many well-known consequences, such as interfering with concentration, learning, and problem-solving. Sleepiness is also an obvious danger on the road.

Sleep lets your heart and vascular system rest. The body releases hormones during sleep, including those related to stress and growth. The immune system creates more infection-fighting cells. All of these important functions are disrupted when a person doesn't get sufficient sleep, which can lead to illness in a variety of ways. "Our goal is to provide information that people can use to make decisions about their lifestyles and sleep that will lead to better health," Dr. Twery says.

Are You Getting Enough Sleep?

You may have a sleep disorder and should see your doctor if:

  • You regularly take more than 30 minutes each night to fall asleep.
  • You regularly awaken more than a few times or for long periods of time each night.
  • You take frequent naps.
  • You often feel sleepy during the day—especially if you fall asleep at inappropriate times during the day.

One way to help your doctor determine if you need help with your sleep is to create a sleep diary for a week or two. It should include what time you go to bed, what time you get up, how you feel when you get up, and what time of day you feel sleepy. Your doctor will also take into account your medical history and may order certain tests to see what might be causing your sleep disturbance. He or she can recommend lifestyle changes or medical treatment to help you sleep better.

Dr. Michael Twery

Dr. Michael Twery:
"Sleep disturbances
increase your health
Photo courtesy of

Sleep Apnea and Children

Snoring is common in children and usually isn't a serious medical concern. But in some children, snoring is a sign of underlying obstructive sleep apnea—a common but potentially dangerous condition during which a person has episodes of stopped breathing while asleep.

Like adults with this nighttime breathing disorder, children with sleep apnea are at risk of developing abnormal blood pressure levels and insulin resistance, which may lead to serious health problems later in life, including heart disease, stroke, and high blood pressure. Sleep apnea can also lead to problems with behavior, growth, and learning, says Susan Redline, M.D., Director of the Case Western Reserve Sleep and Epidemiology Research Center and Director of the Sleep Disorders Center at University Hospitals of Cleveland.

In addition to snoring, children with sleep apnea may snort or gasp. Sleep apnea in children is often caused by large tonsils and adenoids, which are tissues at the back of the nasal cavity and throat. When the throat muscles relax during sleep, the adenoids and tonsils can block the airway.

Dr. Redline is leading a multi-center study of children with sleep apnea funded by the National Heart, Lung, and Blood Institute. The Childhood Adenotonsillectomy Study (CHAT) will compare children who have a tonsillectomy soon after their diagnosis with children who are observed but not treated for seven months. The study will determine the overall effectiveness of this treatment, and will identify whether there are subgroups of children who may need additional treatment to improve their sleep apnea. The researchers also will see if improvement in sleep apnea results in improved health and functioning, including learning abilities and behavior, blood pressure, and growth.

To Find Out More

For more ideas on improving your sleep, download a free copy of the National Heart, Lung, and Blood Institute's "Your Guide to Healthy Sleep" at There is a variety of sleep-related information there. Just click on "Sleep Disorders." And visit for more information.

SIDS and Infant Sleep

Sudden infant death syndrome (SIDS) is the sudden, unexplained death of an infant younger than one year old. Some people call SIDS "crib death" because many babies who die of SIDS are found in their cribs. SIDS is the leading cause of death in children between one month and one year old. Most SIDS deaths occur when babies are between two months and four months old. Although health care professionals don't know what causes SIDS, they do know ways to reduce the risk. These include

  • Placing babies on their backs to sleep, even for short naps—"tummy time" is for when babies are awake and someone is watching
  • Using a firm sleep surface, such as a crib mattress covered with a fitted sheet
  • Keeping soft objects and loose bedding away from sleep area
  • Making sure babies don't get too hot—keep the room at a comfortable temperature for an adult

Summer 2007 Issue: Volume 2 Number 3 Pages 17 - 19