– [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 practicallyevery 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 hypothalamus.
And while it’s most famous for controlling our sleep cycles,
it’s also responsible for helping primary organs
如大脑 心脏 肺等
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’tdisappear after a few days.
And social jetlag is taking its toll on the night owls of the world.
because even if you get therecommended amount of sleep,
knocking your circadian rhythmout of wack has consequences.
For example, one studyfound that for every hour
your circadian rhythm is out of sync,
your risk of obesity increases by 33%.
Also increasing your risk ofthe many health complications associated with obesity
and the problem isn’t just a physical one.
In another study, peoplewhose circadian rhythms
were more than two hours off,
reported notably more severesymptoms of depression.
And since your circadianrhythm tends to shift as your age,
social jetlag isespecially apparent in teens.
In fact, the CDC warnsthat most public schools
across America starttoo early, before 8:30,
which according to thenon-profit RAND Corporation,
is costing the countrynine billion dollars a year
from mainly lost academicperformance and car crashes
from tired teens behind the wheel.
Luckily, the circadianrhythm isn’t set in stone.
Turns out, it’s largelytriggered 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 brightenyour morning a little more.
We’d like to learn what you wan na know about the human body.
Tell us in the commentsand thanks of watching.