Teens and Lack of Sleep: The Impact and What to Do About It
As a whole, adolescents and teens are getting too little sleep. The deficit starts in early adolescence and typically gets worse each year through high school. In fact, about 75-80% of seniors are getting less than eight hours on school nights. The recommended amount for teenagers is 8-10 hours a night.
The causes of too little sleep
The causes of too little sleep are many. First, we know that physiologically, the internal clock of teens shifts later and later and hits its latest point around age 20. Then it starts to go earlier again. That process appears to be development-dependent, not just age dependent. Meaning, the “early bloomers” – the ones who go through puberty earlier – tend to have a later internal clock. In other words, an 8th grade boy who looks like he’s ready to go to college is probably ready for bed later than his peers. Individual differences aside, though, the average adolescent has a later internal clock than they did when they were younger, or than they will when they are their parents’ age.
Second, structured and unstructured after-school activities contribute to later bedtimes. By structured, I mean homework, work, and sports. Unstructured activities are things like the internet, social media and the peer pressure to respond to friends at all hours of the night. Together with the change in internal clock, this pushes bedtimes later and later.
Finally, as kids transition to middle school and high school, start times stay about the same or even get earlier. Many high schools start around 7:30 a.m. The American Academy of Pediatrics recommends that no school should start before 8:30 a.m., as their biological clocks push them to sleep later in the mornings. Between the later bedtimes and the early school starts, most teenagers are in a chronic state of sleep deficit.
The impact of too little sleep
The impact of that sleep deficit is bigger than you might think. We have been studying it at Cincinnati Children’s, and I can sum up our findings in one sentence. Teens getting too little sleep are sleepy, surly, spacey, sedentary, sugared-up, scary on the road, and a little less smart.
Most of that sentence is self-explanatory, but I would like to highlight a few areas. Typically, the first symptom of sleep deprivation is the lack of emotion regulation. I think many parents assume that teens are naturally moody and surly; but in fact, most teenagers are sleep deprived.
In addition to that, there is a correlation between school start times and accident rates. There have been comparison studies between schools that have later start times compared to those with earlier start times. The students attending schools with later start times have less driving accidents. Our data show that this is likely a cause-effect relationship.
Also related to schools, teens’ school performance tends to be worse when they sleep less. It’s not just that they have more trouble paying attention. They actually don’t take in and retain as much information in this sleepy state.
So what can be done about it? Here are six tips to help your teen sleep more:
6 Tips to Help Your Teen Sleep More
Set a bedtime for both school and weekend nights
Many teens don’t have a bedtime at all. It’s important to set a reasonable one during school nights, so that they can get enough sleep. Studies show that adolescents whose parents set a bedtime get more sleep than those who don’t. If possible, avoid big swings in bedtime and wake times on the weekends. Try to keep that schedule within a couple of hours. I mention this because teens are brilliantly good at shifting their body clocks later. And if they are sleeping in late on the weekends, they reset their body clocks later. So when Sunday night rolls around, they have even more trouble falling asleep. And on Monday morning comes, they’ll feel jet lagged.
Get rid of caffeine after lunch – or better yet, get rid of it all together
Caffeine consumed after lunch can most certainly interfere with your teen’s ability to fall asleep earlier. As a side note, teens should limit their caffeine intake to 100 milligrams a day, or quit all together. Read a previous post to understand its impact.
Set limits on screen time
I realize this is a tough one, but it’s important. Screens emit blue light that pushes teens (and adults!) body clocks later. But don’t fool yourself into thinking that the “night shift” feature on a device (which reduces blue light) means that it is OK to have screens at night. The light is only part of the problem. Probably the bigger effect of those devices is that they’re really engaging and difficult to put down, keeping teens up later and restricting their sleep. Ideally, they should be put away an hour before bedtime.
Put phones on airplane mode
Similarly, have your teens turn their phones off or put them on airplane mode while they’re attempting to fall asleep and throughout the night. The last thing we want is for your teen to be really close to drifting off to sleep and receive a vibrating alert.
Establish relaxation time
Teens should take some time to wind down before bedtime. This may mean taking a shower, dimming the lights, reading a book, or listening to relaxing music. Having this type of routine will signal to your brain that it’s time to relax and eventually, sleep.
Advocate for later school start times
This is a complicated subject, and there isn’t an easy solution for schools to push back their start times. But I recommend that parents be a part of the discussion to help their schools find a solution. Many schools understand the health and school performance benefits, but are facing bussing, budgetary and prioritization constraints. They need your input, your support, and your push so that they can do the right thing for teens’ sleep.