It's six o'clock in the morning,pitch(a strong level of feeling about something or a high level of an activity or a quality.)black outside. My 14-year-old son is fast asleep in his bed, sleeping thereckless(not caring or worring about the possible bad or dangerous results of your actions.), deep sleep of a teenager. Iflip(to move a switch so  that a machine or piece of electrical equipment starts or stops.)on the light and physically shake the poor boy awake,because I know that, like ripping off aBand-Aid(a piece of thin material that is stuck to the skin to cover cuts and other small wounds.), it's better to get it over with quickly.

I have a friend who yells "Fire!" just to rouse her sleeping teen. And another who got sofed up(If you are fed up, you are unhappy, board , ot tired of something, especially something that you have been experiencing for a long time.)that she had todump(If you dump something somewhere, you put it or unload it there quickly and carelessly.)cold water on her son's head just to get him out of bed. Sound brutal ... but perhaps familiar?

Every morning I ask myself, "How can I — knowing what I know and doing what I do for a living — be doing this to my own son?" You see, I'm a sleep researcher.

So I know far too much about sleep and the consequences of sleep loss. I know that I'm depriving my son of the sleep he desperately needs as a rapidly growing teenager. I also know that by waking him up hours before his natural biological clock tells him he's ready, I'm literallyrobbing(to steal money or property from a person, bank etc.)him of his dreams — the type of sleep most associated with learning, memory consolidation and emotional processing.

But it's not just my kid that's being deprived of sleep. Sleep deprivation among American teenagers is anepidemic(a large number of cases of a disease that happen at the same time.). Only about one in 10 gets the eight to 10 hours of sleep per nightrecommended(to advise someone to do something, especially because you have special knowledge of a situation or subject.)by sleep scientists andpediatricians(a doctor who studies and treats the diseases of children.). Now, if you're thinking to yourself, "Phew, we're doing good, my kid's getting eight hours," remember, eight hours is the minimum recommendation. You're barely passing.Eight hours is kind of like getting a C on your report card.

There are many factors contributing to this epidemic, but a major factor preventing teens from getting the sleep they need is actually a matter of public policy. Not hormones, social lives or Snap chat. Across the country, many schools are starting around 7:30am or earlier, despite the fact that major medical organizations recommend that middle and high school start no earlier than 8:30am. These early start policies have a direct effect on how much — or really how little sleep American teenagers are getting.They're alsopitting(if two opposing things or people are pitted against one another, they are in conflict.)teenagers and their parents in afundamentally(you use fundamentally for emphasis when you are stating an opinion, or when you are making an important or general statemeng about something.)unwinnable fight against their own bodies. Around the time ofpuberty(the stage of physical development during which you change from a child to an adult and are abole to have children.), teenagers experience a delay in their biological clock, which determines when we feel most awake and when we feel most sleepy. This is driven in part by a shift in the release of the hormonemelatonin(a hormone that is sometimes used as a drug to help you sleep.). Teenagers' bodies wait to start releasing melatonin until around 11pm, which is two hours later than what we see in adults or younger children. This means that waking a teenager up at 6am is the biologicalequivalent(having the same value, purpose, job etc as a person or thing of a different kind.)of waking an adult up at 4am. On the unfortunate days when I have to wake up at 4am, I'm azombie(someone who moves very slowly and does not seem to be thinking about what they are doing, especially because they are very tired.). Functionally useless. I can't think straight, I'mirritable(getting annoyed quickly or easily.), and I probably shouldn't be driving a car. But this is how many American teenagers feel every single school day. In fact, many of the, shall we say, unpleasant characteristics that wechalk up(to earn or achieve:to accumulate)to being a teenager —moodiness(often changing quickly from being in a good temper to being in a bad temper.), irritability, laziness, depression — could be a product ofchronic(a chronic problem is one that continues for a long time and cannot easily be solved.)sleepdeprivation(the lack of something that  you need in order to be healthy, comfortable, or happy.). For many teens battling chronic sleep loss, their go-to strategy to compensate is consuming large quantities of caffeine in the form ofventi frappuccinos,or energy drinks and shots. Soessentially(used when stating the most basic facts about something.), we've got an entire population of tired butwired(feeling very active and excited, especially because you have drunk a lot of coffee or taken a drug.)youth.

Advocates of sleep-friendly start times know thatadolescence(the time, usually between the age of 12 and 18, when a young person is developing into an  adult.)is a period of dramatic brain development,particularly in the parts of the brain that areresponsible( if someone is responsible for an accident , mistake, crime etc, it is their fault or they blamed.)for those higher order thinking processes,including reasoning, problem-solving and good judgment. In other words, the very type of brain activity that's responsible forreining(to start to control a situation more strictly.)in thoseimpulsive(someone who is impulsive does things without considering the possible dangers or problems first.)and often risky behaviors that are socharacteristic(very typical of a particular thing or of someone's character.)of adolescence and that are so terrifying to us parents of teenagers. They know that like the rest of us, when teenagers don't get the sleep they need, their brains, their bodies and behaviors suffer with both immediate and lasting effects. They can't concentrate, their attentionplummets(to suddenly and quickly decrease in value or amount.)and many will even show behavioral signs thatmimic(to copy the way someone speaks or behaves, especially in order to make people laugh.)ADHD(attention deficit hyperactivity disorder.).

But the consequences of teen sleep loss go well beyond the classroom, sadlycontributing(to help to cause something to happen.)to many of the mental health problems that skyrocket during adolescence, includingsubstance use, depression and suicide. In our work with teens from LAUnified (created from more than on part, group)School District, we found that teens with sleep problems were 55 percent more likely to have used alcohol in the past month. In another study with over 30,000 high school students, they found that for each hour of lost sleep, there was a 38 percent increase in feeling sad or hopeless, and a 58 percent increase in teen suicide attempts. And if that's not enough,teens whoskip out（to leave a place quickly in a secret and improper way.)on sleep are at increased risk for a host of physical health problems thatplague(to cause pain, suffering, or trouble to someone, especially for a long period of time.)our country, including obesity, heart disease anddiabetes(a serious disease in which there is too much sugar in your blood.).Then there's the risk of putting a sleep-deprived teen, with a newlyminted(if you describe something as newly minted or freshly minted, you mean that it is very new, and that it has only just been produced or completed.)driver's license, behind the wheel. Studies have shown that getting five hours or less of sleep per night is the equivalent of driving with a blood alcohol content above the legal limit.

Advocates of sleep-friendly start times, and researchers in this area, have produced tremendous sciences howing the tremendous benefits of later start times. The findings areunequivocal(completely clear and without any possibility of doubt.), and as a sleep scientist, I rarely get to speak with that kind of certainty. Teens from districts with later start times get more sleep. To thenaysayers(a person who says something will not work or is not possible:a person who denies, refuses, or opposes something.)who may think that if schools start later, teens will just stay up later, the truth is, their bedtimes stay the same, but their wake-up times get extended, resulting in more sleep.They're more likely to show up for school; school absences dropped by 25 percent in one district. And they're less likely to drop out. Not surprisingly, they do better academically.

So this has realimplications(a possible future effect or result of an action,event, decision etc.)for reducing the achievement gap. Standardized test scores in math and reading go up by two to three percentage points. That's as powerful as reducing class sizes by one-third fewer students, or replacing a so-so teacher in the classroom with a truly outstanding one. Their mental and physical health improves, and even their families are happier. I mean, who wouldn't enjoy a little more pleasantness from our teens, and a little lesscrankiness(bad-tempered.)? Even their communities are safer because car crash rates go down — a 70 percent reduction in one district.

Given these tremendous benefits, you might think, well, this is ano-brainer(a decision that is easy, and that you do not need to think about, used when you want to emphasize that it is really very easy.), right? So why have we as a society failed toheed(to pay attention to someone's advice or warning.)this call? Often the argument against later start times goes something like this:"Why should we delay start times for teenagers? We need to toughen them up so they're ready for the real world!" But that's like saying to the parent of a two-year-old, "Don't let Johnny nap, or he won't be ready for kindergarten."

Delaying start times also presents manylogistical(the practical arrangements that are needed in order to make a plan that involves a lot of people and equipment successful.)challenges. Not just for students and their families, but for communities as a whole. Updating bus routes, increased transportation costs, impact on sports, care before or after school. These are the same concerns that come up in district after district, time and again around the country as school start times are debated. And they're legitimate concerns, but these are problems we have to work through. They are notvalid(a reason, argument etc that is based on what is reasonable or sensible)excuses for failing to do the right thing for our children, which is to start middle and high schools no earlier than 8:30am. And in districts around the country, big and small, who have made this change, they found that these fears are often unfounded and far outweighed by the tremendous benefits for student health and performance, and our collective public safety.

So tomorrow morning, when coincidentally we get to set our clocks back by an hour and you get that delicious extra hour of sleep, and the day seems a little longer, and a little more full of hope, think about the tremendous power of sleep. And think about what a gift it would be for our children to be able to wake up naturally, inharmony(be in harmony with something--to agree with another idea, feeling etc, or look good with other things.)with their own biology.

Thank you, and pleasant dreams.