Every parent will attest that bright-eyed children grow into sleepy adolescents, and the science confirms their observations. There are multiple factors that prevent adolescents from getting the sleep they need, and inadequate sleep has serious consequences – from impaired learning to depressive symptoms, obesity to deadly accidents – all of which are potentially preventable with some practical strategies to promote adequate sleep.
Adolescence is a period of intense growth and development, so it is no surprise that adolescents require a lot of sleep, over 9 hours nightly. But surveys have shown that only 3% of American adolescents get 9 hours of sleep nightly, and the average amount of weeknight sleep is only 6 hours.1 Sleep deprivation is not a problem in childhood, so why can’t adolescents get enough sleep?
Some of the reasons are biological. Adolescent sleep is marked by a phase change in circadian rhythm, so that teens become sleepy about 2 hours later than younger children and need to sleep later to get adequate sleep. There also is a change in sleep homeostasis, so that it takes a teenager longer to feel sleepy after waking. These biological forces are compounded by external forces: school work, athletics, jobs, and the gravitational pull of friendships provide multiple reasons to stay up rather than sleep. Most high schools in the United States start by 7:30 a.m., meaning teens must get up after only 6-7 hours of sleep. Ambitious teenagers are often involved in sports and extracurricular activities which take several hours after every school day. Homework can consume several hours every night. Even with exquisite organization and discipline, it is challenging to fulfill these commitments and still get 9 hours of sleep nightly.
Over the last 15 years, a new factor – screen time – has worsened the adolescent sleep situation. Most teens have an electronic device in their bedroom and use it for homework, entertainment, and socializing well into the night. Multiple studies have confirmed that electronic exposure in the evening is associated with less sleep at night and more day time sleepiness,by competing with sleep and suppression of nocturnal melatonin release, which can delay the onset of sleep.2
It is ironic that many teens are staying up late for homework, when their lack of sleep can interfere with consolidation of learning. It also has powerful effects on working memory and reaction time, making both academic and athletic performance suffer. Chronically sleep-deprived teenagers often complain of difficulty with initiating and sustaining attention, which may lead to a mistaken diagnosis of ADHD, and stimulant treatment may further complicate sleep.
Even a few days of inadequate sleep can lead to anxiety and depressive symptoms, and chronic sleep deprivation is associated with a higher incidence of clinical depression. The relationship between inadequate sleep and depression is also two-way – disrupted sleep is a hallmark of depression. Beyond the links with depression, there appears to be an association between suicide attempts and inadequate sleep. One recent study found a threefold increase in the rate of suicide attempts in those adolescents who were getting less than 8 hours of sleep nightly, compared with their peers who were getting 8 or more hours of nightly sleep. The degree of risk is inversely related to the amount of sleep.3
Good mental health is not the only casualty of inadequate sleep. A growing body of evidence links short sleep duration with an increased risk of obesity. This appears to be mediated by alterations in neurohormones associated with sleep, leading to higher carbohydrate and fat intake, more snacking and insulin resistance.
Anything that compromises attention and reaction time, including sleep deprivation, adds risk to driving, particularly for inexperienced and impulsive adolescent drivers. The National Highway Transportation Safety Administration estimates that drivers 25 and younger cause more than half of all “fall asleep” crashes.
Teenagers generally know that they are exhausted, but the strategies they might use to manage their fatigue can actually make things worse. Sleepy teenagers often consume large amounts of caffeine to get through their days and their homework at night. Caffeine, in turn, interferes with both the onset and quality of sleep, perpetuating the cycle. Even “catch-up” sleep on weekends is a strategy that can contribute to the problem, as it can lead to more disrupted sleep by pushing the onset of school night sleepiness even later.
While growing autonomy is part of why teenagers are sleep deprived, they will consider the caring and informed guidance of their pediatricians about their health. Ask your teenage patients how much sleep they usually get on a school night. It can be validating to show them how sleep deprived they are, and point out how strategies like caffeine and oversleeping might be making it worse. Explain that people (adults, too!) need to make time for sleep just as they might for exercise or friends. Tell them about “good sleep hygiene,” the practice of having consistent sleep times and routines that are conducive to restful sleep. This can include a hot shower before bed, reading for the last 30 minutes before lights out, and no screen time for at least 1 hour before bed. Indeed, it can be powerful to urge that everyone in the family takes screens out of their bedrooms.
Additionally, while they might sleep in on weekends, it shouldn’t be much more than an hour longer than on weekdays. And no naps after school! It is common for teens to feel overwhelmed by their commitments and that sleep must be the first thing to go. Use their growing sense of autonomy to remind them that they get to choose how to use their time, and balance will pay off much more than sacrificing sleep. A practical conversation about sleep can help them to make informed choices and thoughtfully take care of themselves before they head off to college.
Dr. Swick is an attending psychiatrist in the division of child psychiatry at Massachusetts General Hospital, Boston, and director of the Parenting at a Challenging Time (PACT) Program at the Vernon Cancer Center at Newton Wellesley Hospital, also in Boston. Dr. Jellinek is professor emeritus of psychiatry and pediatrics, Harvard Medical School, Boston. Email them at pdnews@frontlinemedcom.com.
Resources
1. “Adolescent Sleep Needs and Patterns: Research Report and Resource Guide.” (Arlington, Va.: National Sleep Foundation, 2000.)
