My three “children” are in their 30s, but I’m still recovering from their teen years—particularly the need to drag them out of bed before sunrise to get to 7:17 classes. Yes, 7:17. And a bus that showed up at 6:23 a.m. (thank goodness for atomic clocks!).
If you’ve ever had, or been, a teenager, you likely understand why this was a nightmare.
Adding to the nightmare was my growing awareness of the active harm I was inflicting on my kids. As a medical writer, I was aware of sleep and circadian research showing that these early hours made it virtually impossible for most teenagers to get sufficient or adequately timed sleep—both essential for virtually every aspect of their growth, development, and function. But to stay in school, as they were legally required to do, they had no choice.
I was hardly alone in recognizing a problem. Organizations including the American Academy of Pediatrics, Centers for Disease Control, and American Medical Association agreed. So did Arianna Huffington and HuffPost Rise, which made a cool little video of me making the case to start school later. I knew this video was cool because my son, then a college student, texted me that it was “trending.” In fact it got over 13 million views!
But the start times wouldn’t budge. Even though parents, health professionals, and educators in my school district had been trying to change things since 1998, adult vested interests kept overriding the best interests of the kids.
The same story was playing out all over the country. In fact, to this day many secondary U.S. middle and high schools still start class in the 7 a.m. hour, with bus pick-ups beginning even earlier and students waking as early as 4:30 or 5 a.m. to make it to class on time.
Why Anyone Should Care?
A staggering array of research shows that teenagers who don’t get sufficient sleep set themselves up for lifelong health problems, as well as increased risks of depression and suicidal ideation; disciplinary issues, car crashes, and substance use/misuse; and, among other problems, impaired immunity, memory, attention, and judgment, and school performance.
Insufficient sleep is a fact of life for most American teenagers. Recent national surveys show that over 80% of US teenagers are getting less than recommended amounts of sleep on school nights, with nearly 40% getting 6 or fewer hours. Given that typical adolescents need about 9 hours per night for optimal growth, development, and function, these are scary numbers. And study after study bears them out.
With sleep essential to growth, development, and virtually every aspect of human functioning, these findings do not bode well.
Sleep scientists define “insufficient” not just as too little sleep, but also as irregular and/or poorly timed sleep, both also extremely common in teenagers—especially the many who “sleep in” on weekends but have to rise at dawn on schooldays. Insufficient sleep becomes increasingly prevalent as students progress through high school. with minority, urban, and students from lower socioeconomic status groups most greatly affected.
What Does All This Have to Do With School Start Times?
There are obviously many reasons why teenagers aren’t getting sufficient sleep (more on that below). But leading the list is a clash between non-negotiable school start times and even more non-negotiable biology.
The biology part is due to two concurrent changes at puberty: 1) a reduction in the “homeostatic drive” to sleep”—i.e., the ability to resist the pressure to sleep that builds the longer you’re awake, and 2) temporary shifts in the sleep-wake cycle that delay the body clock (circadian rhythms) by 2-3 hours.
This shift explains why most teenagers struggle to fall asleep or wake as early as they did when they were younger. Sure, some stay up even later than their bodies are telling to doing homework, texting, gaming, whatever. But even teenagers who try to go to bed at 8:30 p.m. find themselves lying awake for hours. You can “put” a 16-year-old to bed, but you can’t make them sleep.
So now the problem with 5 a.m. alarms is clear. If teens aren’t falling asleep until 11, 12, or beyond—and sleep app data confirms that most are not—then waking at dawn is going to rob them of sleep. To get enough sleep and make it to school on time (which they are required by law to do), most 16-year-olds should be asleep by 8:30 or 9 p.m.—unrealistic for many for both biological and social reasons.
The problem is not just that teenagers are not getting healthy sleep. The problem is that with current school hours, most teenagers cannot get healthy sleep.
After a week of too little sleep, many teenagers “sleep in” on weekends, creating a state of permanent “jet lag” (“social jet lag”), as if they flew coast-to-coast and back every single week. It doesn’t help that REM (rapid-eye movement) sleep—the stage believed to be critical for emotional regulation and memory consolidation—is concentrated in the last third of the night, i.e., in those early morning hour when we’re often forcing teens out of bed.
In short, the issue is not just that teenagers are not getting healthy sleep. The issue is that with current school hours, most teenagers cannot get healthy sleep.
Wouldn’t It Just Be Easier to Take Away Their Phones?
If you’re inclined to blame lazy teens, bad parents, screens, or social media, think again: scientists have found the same delayed cycle at puberty in animals, including rodents and primates—who presumably don’t have cell phones.
Of course, school start times are by no means the only factor underlying teen sleep problems. Other factors including biologic changes at puberty, cultural forces, systemic challenges, and individual behaviors and sleep disorders. Some of these factors are hard if not impossible to address, starting with adolescent biology and including a general de-valuing of sleep and electric lights extending natural daylight in our homes.
If you’re thinking this is due to misusing electronics, think again: scientists have found the same delayed cycle at puberty in animals, including rodents and primates—who presumably don’t have cell phones.
Some behaviors—including overuse of devices, social media, and caffeine—have been implicated. However, we have no evidence that they can be addressed effectively and sustainably, particularly across an entire population. Nor do we have rigorous studies about the contribution of late-night sports and rehearsals or midnight homework deadlines, or feasible, effective ways to address them.
Here’s the bottom line: Too-early school start times remain the only factor proven to be both a major and remediable contributor to teen sleep insufficiency on a population level. Hundreds, if not thousands, of communities around the USA and the world have found feasible ways to start class at later, healthier hours. And those that do so consistently find students get more and better timed sleep, along with lower rates of depression and anxiety, substance misuse, and even automobile crashes, along—particularly among students from disadvantaged backgrounds—with absence, tardy, and drop-out rates.
The whole community benefits from these changes. The RAND Corporation even estimated that delaying all middle and high school start times in the country to 8:30 a.m. or later would contribute $83 billion to the U.S. economy after just 2 years, with benefits far outweighing any costs of change. And that’s a conservative estimate.
So, why don’t we (or can’t we) do something about this? Stay tuned!