Peculiar facts about shut-eye.
What really happens when your head hits the pillow? Sure, sleep
fulfills some very basic needslike maintaining your physical and
mental health, not to mention preparing you for those crucial
daytime hours. But a lot more happens after the lights go out. Did
you know that sleep affects your memory, your heart, and even the
health of your teeth?
Flexing Memory
From a special vacation to a holiday gathering, long-term memories
are predominantly formed during sleep when the brain replays recent
experiences. But how do you remember what happens when? According
to researchers at the University of Lubeck in Germany, shut-eye not
only strengthens a memory's content but also the sequence in which
they are experienced. Students were presented sets of words in a
particular order. One group of these students was allowed to sleep
and another was not. Those who were allowed to sleep could more
often recall the order of words than those who were not allowed to
sleep.
Sleep to a Better Beat
A good night's sleep is essential for a healthy ticker. Lack of
sleep can lead to hypertension, a condition in which blood pressure
is chronically elevated. Of course, with it comes a higher risk of
heart attack or stroke. Even normal, healthy people, who are
persistently deprived of proper sleep, suffer increased risk of
hypertension, say researchers at the American Academy of Sleep
Medicine. Ongoing sleep deprivation can set up chemical and
hormonal changes in the body, including the release of stress
hormones like adrenaline.
Snooze and Smile
Tossing and turning can affect your smile. A Journal of
Periodontology study shows that the amount of sleep you get can
significantly affect your teeth. While smoking negatively impacted
oral health the most, hours of sleep closely followed. The study
tracked 219 Japanese factory workers from 1999 through 2003.
Participants who slept seven to eight hours a night had less
periodontal disease than those who slept six hours or less a night.
Researchers speculate that sleep shortage impairs the body's immune
system, something that can lead to bad teeth.
Sleep to Your Own Rhythm
If you find yourself awake and energetic late at night, you may
have a genetic mutation. The altered gene may explain why some
people prefer late nights. This gene affects the body's circadian
cycle-the clock that keeps our metabolism, digestion, and sleep
patterns in sync. Researchers discovered abnormally long circadian
rhythms in some mice-lasting about 27 hours instead of the normal
cycle of 24 hours. These mice had the mutated gene. Also, night
owls who compensate by staying in bed longer still experience more
insomnia than the rest of us. Also, night owls report feeling less
in control of their sleep, which may also fuel insomnia.
Getting by with Less
Some people can survive on very little sleep, while others require
many hours to function normally. If you still perform relatively
well when sleep deprived, the reason could be your genes. In one
study from the University of Surrey, some people struggled to stay
awake after two days of no sleep while others had no problem
whatsoever. The researchers looked into this further and gave the
participants the opportunity to sleep normally; they found that
some participants spend more time in slow-wave sleep, the deepest
form of shut-eye. And for them carrying a sleep debt makes it that
much harder to stay alert and function.
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