Sleep deprivation is bad news. Really bad news. Both short-term and chronic sleep deprivation can impair metabolic function, immune function, and cognitive function, a frighting mix that may in turn result in poor academic performance, memory difficulties, and mood swings [1, 2]. If all that goes on long enough, sleep deprivation can even cause hallucinations .
Teenagers, given hectic academic and social schedules, are prone to staying up late — usually without being given the possibility to sleep in. This can quickly lead to an "overdraft" with the "sleep bank". Yup, we're living in a culture where raising teenagers you get along with is seen as all but impossible, and parents are scratching their heads about how to deal with teenagers. Could your teen's emotional outbursts, seeming lack of devotion to school work, and general grump be explained by something other than adolescence, though?
How Much Sleep Do Teens Really Need?
You've heard the tired (pun intended) old "eight hours a night" rule for adults — but the truth is that sleep needs do vary from person to person. Teenagers, on average, require between eight and 10 hours of sleep a night to function at their best. Research, unfortunately, suggests that most teens fall way short, with one study finding that only 15 percent of teenagers get at least eight and a half hours of shut eye every night on school nights. 
Teens' lack of sleep can, in large part, be blamed on a combination of shifting natural wake-sleep cycles and school schedules. That is, it's common for teens not to be able to fall asleep before 11 pm, for biological reasons, but school starts when it does, so they still have to get up. Their bodies then try to make up for the sleep deficit they've built up over the week by sleeping in late on weekends — which has the unfortunate side effect of messing with their biological clocks. 
What Does This Sleep Deprivation Mean For Your Teen's Health?
We already looked at all the big things right in the introduction, but there's more. One study found that teenagers who performed less well in school, attaining Cs, Ds, and Fs, got less sleep than those who got As and Bs. Poor grades are additionally often accompanied by daytime sleepiness, behavioral problems, and even depression. 
Teens themselves are, of course, quite aware of how they feel when they are not getting enough sleep, even though they may not recognize the root cause of their feelings — Thirty-three percent of 12 to 18 year old individuals participating in one study reported they were so sleepy they occasionally fall asleep at school . What's next? Well, the same study showed that they turn to caffeinated drinks in a bid to stay awake. While this may improve their short-term ability to concentrate, that doesn't do any good in the long-term.
Another big problem is the nightly use of technology now common among teenagers  — and, to be fair, probably the rest of us, too. Together with academic obligations, social desires, and the natural shift to later bedtimes, this results in a uniquely modern challenge. I've combed through many more studies that demonstrate the impact sleep deprivation has on a teenager's academic performance, but I'm not going to talk about them in any more detail, because a teenager's well-being is about so much more than that. People function best when they're alert and content, and a lack of sleep easily strips us of these basics. It's really no wonder that a low-conflict relationship with your teen seems out of reach when they're running on empty!
The question is — what can you, as a parent, do to make sure your teenager gets enough sleep?
Sleep Hygiene 101
Nope, your teens probably won't like all of these suggestions, not until they've caught up on their sleep enough to think about them rationally. Here are the "sleep hygiene 101" tips anyway:
- Caffeine consumption may keep your teen awake for longer, but it has also been shown to disrupt sleep. It is actually best to not use caffeine within the last six hours before you go to sleep. 
- Make the bedroom a technology-free zone. This poses a challenge for teenagers, who often do homework on their computers in the rooms they also sleep in, and then go to bed with their cell phones under their pillows. If your teen's schedule at all allows it, encourage them to finish using their computers quite some time before they to go sleep. Definitely consider instituting a "cell phone bedtime". 
- Encourage your teen to establish a relaxing bedtime routine, such as taking a shower and putting on jammies, then reading a book for a while before turning the lights out and keeping them that way. Nothing too stressful should ideally be done right before bed. Eating, drinking, and working out are also not great things to do in the last few hours before going to bed. 
- It might be ideal if school started a few hours later, but hey, it usually doesn't. Calculate bedtimes to allow for at least eight hours of sleep, keeping in mind that almost nobody falls asleep immediately after hitting the pillow.