How much sleep did your child get last night? Sleep is integral to daily and long-term health. Yet 66 percent of 9th and 78 percent of 12th graders in the United States do not get the recommended number of hours of sleep per night.
What can happen to children and youth when they don’t get enough sleep? What can we do to improve sleep for people of all ages? On the eve of National Sleep Awareness Week, here’s a roundup of the wide-ranging research on the topic—enough for every letter of the alphabet.
A: Adolescents. Teenagers have a reputation for frequently staying up late, sleeping in, and generally not getting enough sleep. Sleep deprivation has been described as an epidemic. Although it is recommended that teens get 8 to 10 hours of sleep a night, the average high school senior only sleeps 6.9 hours.
B: Biological clock. Our bodies have circadian clocks that regulate our periods of sleepiness and wakefulness. This natural rhythm causes us to be more awake at certain parts of the day and is part of what determines who is an “early bird” or “night owl.” Periods of wakefulness and alertness also shift throughout one’s life. For example, younger children have more energy in the early morning, while teenagers often find it hard to go to sleep before 11 p.m.
C: Cycle. In addition to being attuned to a 24-hour day/night cycle, our sleeping brain emits different waves on a cycle that lasts about 90 minutes for adults and 50 to 60 minutes for newborns. These cycles of rapid-eye-movement (REM) and non-REM sleep help us recuperate and process the day’s events. Being woken up in the middle of REM sleep can leave you groggy.
D: Disorders. As with many aspects of health, there are irregularities and disorders associated with sleep. The onset of sleeping disorders varies throughout the life course. For example, narcolepsy—a condition marked by extreme tiredness and spontaneous sleep during the day—often first affects people between the ages of 15 and 25.
E: Exercise. If you are having a hard time falling asleep or are not sleeping well, research indicates that exercise is an effective way to improve sleep quality without resorting to medication.
F: Focus. The ability to focus is an important benefit of a good night’s sleep. The relationship between focus, energy, and sleep is especially important for adolescents. Research has established that pushing back the start time of middle and high schools is associated with greater attendance, improved academic performance, more alertness, and fewer traffic accidents.
G: Gadgets. Sleep, like so much else, has gone high-tech. Sleep apps, trackers, smart alarm clocks, special light bulbs, and other gizmos aim to improve sleep. However, the jury is still out about whether these products do what they claim—and in some cases, they may impede sleep.
H: Health. Too little sleep can hurt our mental and physical health. Particularly among adolescents, lack of sleep is associated with increases in suicidal thoughts, substance abuse, and anxiety disorders. Over the course of a person’s life, insufficient sleep also can contribute to chronic conditions such as diabetes, obesity, and heart disease.
I: Infants. Experts recommend that infants (4 to 12 months old) get 12 to 16 hours of sleep a day, including naps.
J: Journaling. Keeping track of your sleep habits in a diary can help you find patterns and develop strategies to improve sleep.
K: Kids. School-aged kids (6 to 12 years old) should get between 9 and 12 hours of sleep per night.
L: Learning. The relationship between brain chemistry, sleep, and learning is complex. Recent theories suggest that during sleep our brain trims synapses (i.e., neural connections) to help us selectively forget, so we can learn new information. Learning can be negatively influenced by sleep deprivation through mood alteration, lack of focus, impaired judgement, and fatigued neurons (brain cells).
M: Memory. Scientists have only begun to understand how the brain makes and stores memories. Sleep plays a central role in most theories, especially in transferring memories from the short-term to long-term memory and making them accessible for future recollection.
N: Naps. Naps are an important supplement for night-time sleep, especially for children under 5 years old. But everyone can benefit from the increased alertness and mood boost from a 20- to 30-minute nap. However, if you are struggling to fall asleep at night, it’s best to avoid sleeping in the afternoon.
O: Outcomes. Homework and school demands are often cited as reasons teens do not get enough sleep. However, research and surveys have shown an association between sleeping more and having better academic outcomes, like higher grades.
P: Positions. For newborns and infants, sleep position could be a matter of life and death. Newborns should sleep on their backs, not bellies or sides, to help prevent sudden infant death syndrome.
Q: Quiet. A quiet bedroom is important for quality sleep. Background noise such as a television can hinder sleep quality and cause drowsiness the next day, even after a full night of sleep. Furthermore, research indicates that environmental noise such as transportation, especially at night, can have long-term negative impacts on children’s health.
R: Routine. Going to bed and waking up at the same time each day establishes a pattern, solidifies the body’s biological clock, and boosts energy levels. Routines help people of all ages, but they can be particularly helpful for newborns, school-age kids, and adolescents.
S: Screen time. Using computers, televisions, and smart phones close to bedtime can impact sleep. Lights from screens can suppress melatonin, the hormone that tells us to go to sleep, and make it harder to fall asleep. In a review of the role of screens in children’s sleep, researchers found that screen time was associated with shortened sleep times, especially for teens.
T: Tips. General tips (some specifically for teens) for improving sleep include establishing a routine, building in winding-down time, exercising, avoiding caffeine, and keeping your bedroom cool, between 60 and 67 degrees.
U: Unequal. There are sleep health disparities by income and by race and ethnicity. Low-income children face greater risk of poor-quality sleep because of environmental factors like noise and overcrowding. However, higher-income adolescents report shorter sleep durations. Sleep challenges have also been associated with increased risk for obesity among black adolescents and childhood asthma among Latinos.
V: Vehicles. By one estimate, accident rates for drivers who got 4 to 5 hours of sleep are more than 4 times higher than those for drivers who slept for 7 or more hours. This is comparable to drunk driving accident rates. Even drivers who sleep 5 to 6 hours are twice as likely to be in an accident relative to those who sleep 7 hours. Young drivers—those under age 25—are especially likely to drive while drowsy; 15 percent of 10th to 12th graders who drive reported driving drowsy once a week.
W: Walking. Sleepwalking can result in accidental injury and disorientation. Prevalence is highest among 3- to 7-year-olds and children with sleep apnea.
X: (E)Xcessive daytime sleepiness. Try as we might, sometimes we just can’t seem to stay awake. In fact, in 2012, nearly 40 percent of adults reported accidently falling asleep in the day. Among adolescents, the number ranges from 20 to 60 percent.
Y: Young children. Quality sleep is crucial for brain development. Poor-quality sleep during early childhood is linked to impairment of social-emotional and cognitive functioning. However, 20 to 50 percent of 3- to 5-year-olds experience sleep problems.
Z: Zen. Sleep should be relaxing and peaceful. Sweet dreams!