- [Narrator] There is plenty of advise
for how to improve your sleep.
Go to bed at the same time,
avoid digital screens after dark, and don't hit snooze.
But it all comes down to the same assumption,
that you're doing something wrong.
When in fact, it may not be your fault at all.
Inside practically every organism on earth,
there's a clock that keeps order.
Known as a circadian rhythm.
For humans, it's located in the part of our brain
called the hypothalamus.
And while it's most famous for controlling our sleep cycles,
it's also responsible for helping primary organs
like the brain, heart, and lungs work in harmony.
But not everyone's circadian rhythm is the same.
Night owls for instance, generally feel tired
later than early birds.
Often because they produce high amounts
of the sleep hormone melatonin later at night.
And for most of human history, that didn't matter.
Since night owls could protect their tribes
from nocturnal predators,
or their cities from cunning conquerors.
But society has made it a problem in recent decades.
An estimated 80% of Americans follow daily schedules
that fall between 6AM and 6PM.
Yet nearly a 1/3 of the population
considers themselves night owls,
which means they're better off with a schedule
that looks more like this.
This phenomenon is called social jetlag.
It's like the jetlag you feel after a long plane trip
but worse because it doesn't disappear after a few days.
And social jetlag is taking its tole
on the night owls of the world
because even if you get the recommended amount of sleep,
knocking your circadian rhythm out of wack has consequences.
For example, one study found that for every hour
your circadian rhythm is out of sync,
your risk of obesity increases by 33%.
Also increasing your risk of the many health complications
associated with obesity
and the problem isn't just a physical one.
In another study, people whose circadian rhythms
were more than two hours off,
reported notably more severe symptoms of depression.
And since your circadian rhythm tends to shift
as you age, social jetlag is especially apparent in teens.
In fact, the CDC warns that most public schools
across America start too early, before 8:30,
which according to the non-profit RAND Corporation,
is costing the country nine billion dollars a year
from mainly lost academic performance and car crashes
from tired teens behind the wheel.
Luckily, the circadian rhythm isn't set in stone.
Turns out, it's largely triggered by light signals
that strike your eye.
So when you first wake up,
get outside and soak up some morning sun.
Or if that's out of the question,
make sure your home is well-lit.
It might just brighten your morning a little more.
We'd like to learn what you wanna know about the human body.
Tell us in the comments and thanks of watching.