More than 50% of teenagers feel sleepy during the day. Perhaps because more than 80% of teenagers in America don’t get the necessary nightly sleep each night.
The National Sleep Foundation (NSF) poll revealed that our adolescents sleep 7.6 hours on school nights, even though they feel they need an average of 8.2 hours of sleep for optimal day time function. Light is the main environmental stimulus that synchronizes the intrinsic human circadian period to the 24-hour day.
Melatonin, a hormone secreted by the pineal gland, induces evening drowsiness and also maintains the sleep-wake cycle. Light blocks the secretion of melatonin; therefore, light exposure at bed time can delay sleep initiation.
Causes of Insufficient Sleep
According to a 2006 NSF poll, most adolescents (97%) have an electronic device in their bedrooms. Seventy percent of adolescents report watching TV within one hour of bedtime. More than 50% use their computers after 9pm. Other night time activities include watching DVDs, using cell phone, and playing video/computer games. The light stimulation associated with use of these electronics close to bedtime may exacerbate their natural night-owl tendencies.
Caffeine consumption, which is highly prevalent at this age, may be another factor that delays the onset of sleep.
Other activities that keep teenagers up at night include homework, extracurricular activities (eg: athletics), jobs, and socializing.
Implications of Insufficient Sleep
Difficulty waking up in the morning can result in tardiness and absence from school. Poor attendance and inattentiveness in class adversely affects grades. Adequate sleep is also necessary for memory consolidation and learning enhancement.
Another NSF poll reports more than 50% of surveyed adolescents who drive reported driving sleepy in the past year! In an analysis of all U.S motor vehicle accidents occurring between 1999 and 2008, 16.5% of fatal crashes involved a drowsy driver.
Athletes in middle and high school who slept 8 hours or more per night were almost 70% less likely to be injured than athletes who got less sleep, according to study results presented at this past year’s American Academy Of Pediatrics National Conference and Exhibition, which I attended.
For more on the importance of sleep for teens, including how much sleep teens need and practical suggestions to help them get it, see this excelelnt Contemporary Pediatrics handout.
Dr. K.G. Pai is the founding father of the Kids Plus practice family.