Tired? We all know the feeling; irritable, groggy and exceptionally lazy. Chances are
you didn't sleep enough last night, or the past few nights. But what exactly is "enough sleep?"
And more importantly, can you ever "catch up" on it?
While the very function of sleep is still debated by scientists, we do know that it's
necessary to function efficiently and productively. After all, we spend 24 years of our lifetime
sleeping, it had better be important. Researchers have tested how much is required each night
by assigning groups of people to four, five, and eight hours of sleep over extended periods of
time. After 14 days, those with eight hours of sleep exhibited few attention lapses of cognitive
issues; however, those with six or four hours of sleep showed a steady decline. In fact, after
only two weeks, the six hour group showed a similar reaction time to a person with a blood alcohol
concentration of 0.1%, which is considered legally drunk. The four hour sleepers suffered
even more, occasionally falling asleep during their cognitive tests. In both groups, brain
function decreased day by day, almost linearly with no sign of leveling off.
Scientists have dubbed this cumulative effect as sleep debt. So can we recover from it?
After a night or two of little sleep, studies show that the body and brain can fully recover
with a few nights of good sleep. However, with long term sleep deprivation on the scale
of weeks to months, the recovery of cognitive function is much slower, requiring many more
nights of quality sleep. On the timescale of months to years, it is unknown whether
brain function can be fully repaired, or if it causes permanent damage. Paradoxically,
with chronic sleep deprivation, your sleepiness or how tired you feel does eventually level
off, meaning that you become less and less aware of your objective impairment over time.
So how long should you sleep? Most studies tend to show that seven to eight hours of sleep is the
average ideal for humans. Apart from the cognitive issues, individuals who consistently sleep
less than seven hours a night have an increased risk of heart disease, obesity and diabetes,
not to mention a 12% higher risk of death. On the flip side, studies have shown that
while sleeping more than eight hours does not impair brain function, it also carries an
increased risk of heart disease, obesity and diabetes, and a 30% increased risk of mortality!
So too much sleep may also be a bad thing.
But variation most certainly exists, and our genetics play a large role. In fact, individuals
genuinely unaffected by only six hours of sleep were found to have a mutation of a specific
gene. When scientists genetically engineered mice to express this gene, they were able
to stay awake for an extra 1.2 hours than normal mice. It turns out these short sleepers
have more biologically intense sleep sessions than the average person.
Ultimately, while it's important to know the ideal average of seven to eight hours exists, let
your body and brain help you figure out its own needs. After all, no one shoe size fits
all. If you want to know how to get better quality sleep each night in order to conquer
the hurdles of sleep deprivation, we have some tips and research for you over on ASAPThought.
You can find a link in the description below to that video.
Thanks to Audible.com for giving you a free audio book of your choice at audible.com/asap.
Audible is the leading provider of audio books with over 150,000 downloadable titles across
all types of literature. We recommend the 'A Song of Ice and Fire' series, which
the Game of Thrones TV show is based off of. It's kept us up through the nights and caused
a lot of lost sleep! You can download this audio book or another of your choice for
free at audible.com/asap. And with a subscription you can get one free book a month, so you can
read the whole series! Special thanks to Audible for making these videos possible.
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