When it comes to sleep the deck is already stacked against the teenager. A circadian rhythm is a 24-hour cycle in the physiological process of all living things; it determines when certain biological activities will take place (hormone production, cell regeneration, sleep, etc.). The typical adolescent undergoes a change in their circadian rhythm sometime in middle school, which makes them more alert later in the day.
According to the National Sleep Foundation, the typical teenager needs an average of 9 ¼ hours of sleep each night. With their biological clock keeping them up until around midnight, and school start-times between 7:30-8:30 a.m., there is almost no margin of error for the teen.
Short term, a lack of sleep can prolong a dip in a teen’s circadian rhythm, extending the dip by a few hours. Long term, a lack of sleep can lead to more sickness (due to a 30-40 percent drop in T-cells), frequent headaches, increase anxiety and risky behaviors—like using drugs and alcohol. Furthermore, a study from the Journal of Sleep found that teenagers who go to bed after midnight are more likely to suffer from depression and to consider harming themselves than those who are in bed before 10 p.m.
A person’s circadian rhythm is pretty much determined, but a person’s ability to sleep can be easily influenced by external forces. For example, a 2008 study—funded by various cellphone companies—found that “during laboratory exposure to 884 MHz wireless signals, components of sleep, believed to be important for recovery from daily wear and tear, are adversely affected.”
The cellphone has broken down the wall between public and private life. Teenagers may leave school, but their friends are always one text away. According to research done in 2010, one in three teens sends more than 3000 texts a month. There have even been reports of teens texting while asleep. If the hidden, pervasive effects of cell phone radiation are not bad enough, just think about all of your child’s friends in their rooms with their phones. Inevitably, someone will send a text. A quick, meaningless text can pull your child out of the sleep cycle, even if he or she thinks better of responding.