Teenagers are known for being night owls, and recent studies have investigated just how much sleep teens are actually getting. The Journal of Adolescent Health found that two-thirds of students in high school are getting less than seven hours per night, and only about 10% are getting the nine hours required by most teens to function best during the day. Girls and students in higher grades showed the largest sleep deficits.
Teens face several barriers when it comes to sleep, some of which are unpreventable. The natural sleep-wake pattern shifts during adolescence, making it difficult to wake-up and go to sleep early. In fact, it is normal for teenagers to not be able to fall asleep before 11:00 pm. This is due to a lengthening (or slowing) of the circadian clock in the brain, and therefore there is a biological basis for this tendency. However, teens also typically worsen this tendency by developing irregular sleep-wake patterns across the span of a week – staying up late, and sleeping-in on weekends. In addition, teens are affected by emerging social changes including a hectic lifestyle – balancing homework, jobs, activities, and family obligations in many circumstances, which may increase stress and decrease the priority of sleep. The growth of technology such as computers and cell phones may also present a distraction for teens and push bedtime back even later. These factors combined with early school start times equate to a sleep deficit in most teenagers.
The lack of sleep among teenagers causes major concerns: several studies show that that sleepy students perform poorer in school as they are less alert and have impaired psychological functioning. The risks escalate when considering that teen sleep deprivation is also linked to other health problems such as headaches and a weakened immune system, as well as depression and suicide.
Some school boards have recently implemented later school start times, beginning at 10:00 – 11:00 am, in an attempt to better accommodate the sleep needs of teenagers. Studies have so far found that this measure does help teens get the extra hour or two that they need and improves school attendance and academic performance.
For the majority of teens who do not attend a late-start school, the National Sleep Foundation recommends setting a regular bedtime prior to 10:00 pm on school nights. Other studies have found a strong link between routine physical exercise and improvement in sleep habits among adolescents.