Thursday, 19 June 2014
How Much Sleep Do You Really Need?
By Psych
Central Staff
The amount of sleep each person needs depends on many factors,
including age.
Infants generally require about 16
hours a day, while teenagers need about 9 hours on average. For most adults, 7
to 8 hours a night appears to be the best amount of sleep, although some people
may need as few as 5 hours or as many as 10 hours of sleep each day.
Women in the first 3 months of
pregnancy often need several more hours of sleep than usual.
The amount of sleep a person needs
also increases if he or she has been deprived of sleep in previous days.
Getting too little sleep creates a “sleep debt,” which is much like being
overdrawn at a bank. Eventually, your body will demand that the debt be repaid.
We don’t seem to adapt to getting
less sleep than we need; while we may get used to a sleep-depriving schedule,
our judgment, reaction time, and other functions are still impaired.
People tend to sleep more lightly
and for shorter time spans as they get older, although they generally need
about the same amount of sleep as they needed in early adulthood. About half of
all people over 65 have frequent sleeping problems, such as insomnia, and deep
sleep stages in many elderly people often become very short or stop completely.
This change may be a normal part of aging, or it may result from medical problems
that are common in elderly people and from the medications and other treatments for those problems.
Experts say that if you feel drowsy
during the day, even during boring activities, you haven’t had enough sleep. If
you routinely fall asleep within 5 minutes of lying down, you probably have
severe sleep deprivation,
possibly even a sleep disorder.
Microsleeps, or very brief episodes
of sleep in an otherwise awake person, are another mark of sleep deprivation.
In many cases, people are not aware that they are experiencing microsleeps. The
widespread practice of “burning the candle at both ends” in western
industrialized societies has created so much sleep deprivation that what is
really abnormal sleepiness is now almost the norm.
Many studies make it clear that
sleep deprivation is dangerous. Sleep-deprived people who are tested by using a
driving simulator or by performing a hand-eye coordination task perform as
badly as or worse than those who are intoxicated. Sleep deprivation also magnifies
alcohol’s effects on the body, so a fatigued person who drinks will become much
more impaired than someone who is well-rested.
Driver fatigue is responsible for an
estimated 100,000 motor vehicle accidents and 1500 deaths each year, according
to the National Highway Traffic Safety Administration. Since drowsiness is the
brain’s last step before falling asleep, driving while drowsy can — and often
does — lead to disaster. Caffeine and other stimulants cannot overcome the
effects of severe sleep deprivation. The National Sleep Foundation says that if
you have trouble keeping your eyes focused, if you can’t stop yawning, or if
you can’t remember driving the last few miles, you are probably too drowsy to
drive safely.
