What Is Dehydration?
Dehydration is a condition that occurs when a person loses more
fluids than he or she takes in. Dehydration isn't as serious a
problem for teens as it can be for babies or young children. But if
you ignore your thirst, dehydration can slow you down.
Our bodies are about two thirds water. When someone gets
dehydrated, it means the amount of water in his or her body has
dropped below the level needed for normal body function. Small
decreases don't cause problems, and in most cases, they go
completely unnoticed. But losing larger amounts of water can
sometimes make a person feel quite sick.
Causes of Dehydration
One common cause of dehydration in teens is gastrointestinal
illness. When you're flattened by a stomach bug, you lose fluid
through vomiting and diarrhea.
You might also hear that you can get dehydrated from playing
sports. In reality, it's rare to reach a level of even moderate
dehydration during sports or other normal outdoor activity. But if
you don't replace fluid you lose through sweat as you go, you
can become dehydrated from lots of physical activity, especially on
a hot day.
Some athletes, such as wrestlers who need to reach a certain
weight to compete, dehydrate themselves on purpose to drop weight
quickly before a big game or event by sweating in saunas or using
laxatives or diuretics, which make a person go to the bathroom
more. This practice usually hurts more than it helps, though.
Athletes who do this feel weaker, which affects performance. They
can also have more serious problems, like abnormalities in the salt
and potassium levels in the body. Such changes can also lead to
problems with the heart's rhythm.
Dieting can sap a person's water reserves as well. Beware of
diets or supplements, including laxatives and diuretics that
emphasize shedding "water weight" as a quick way to lose
weight. Losing water weight is not the same thing as losing actual
fat.
Signs of Dehydration
To counter dehydration, you need to restore the proper balance
of water in your body. First, though, you have to recognize the
problem.
Thirst is one indicator of dehydration, but it is not an early
warning sign. By the time you feel thirsty, you might already be
dehydrated. Other symptoms of dehydration include:
- feeling dizzy and lightheaded
- having a dry or sticky mouth
- producing less urine and darker urine
As the condition progresses, a person will start to feel much
sicker as more body systems (or organs) are affected by the
dehydration.
Preventing Dehydration
The easiest way to avoid dehydration is to drink lots of fluids,
especially on hot, dry, windy days. Water is usually the best
choice. Drinking water does not add calories to your diet and can
be great for your health.
The amount that people need to drink will depend on factors like
how much water they're getting from foods and other liquids and
how much they're sweating from physical exertion.
When you're going to be outside on a warm day, dress
appropriately for your activity. Wear loose-fitting clothes and a
hat if you can. That will keep you cooler and cut down on sweating.
If you do find yourself feeling parched or dizzy, take a break for
a few minutes. Sit in the shade or someplace cool and drink
water.
Sports and Exercise
If you're participating in sports or strenuous activities,
drink some fluids before the activity begins. You should also drink
at regular intervals (every 20 minutes or so) during the course of
the activity and after the activity ends. The best time to train or
play sports is in the early morning or late afternoon to avoid the
hottest part of the day.
Gastrointestinal Infections
If you have a stomach bug and you're spending too much time
getting acquainted with the toilet, you probably don't feel
like eating or drinking anything. But you still need fluids. Take
lots of tiny sips of fluids. For some people, ice pops may be
easier to tolerate.
Caffeine
Caffeine is a diuretic, meaning it causes a person to urinate
(pee) more. It's not clear whether this causes dehydration or
not, but to be safe, it's probably a good idea to stay away
from too much caffeine in hot weather, during long workouts, or in
other situations where you might sweat a lot.
When to See a Doctor
Dehydration can usually be treated by drinking fluids. But if
you faint or feel weak or dizzy every time you stand up
(even after a couple of hours) or if you have very little urine
output, you should tell an adult and visit your doctor. The
doctor will probably look for a cause for the dehydration and
encourage you to drink more fluids. If you're more
dehydrated than you realized, especially if you can't hold
fluids down because of vomiting, you may need to receive fluids
through an IV to speed up the rehydration process. An IV is an
intravenous tube that goes directly into a vein.
Occasionally, dehydration might be a sign of something more
serious, such as diabetes, so your doctor may run tests to rule out
any other potential problems.
In general, dehydration is preventable. So just keep drinking
that H2O for healthy hydration.
Reviewed by:
Mary L. Gavin, MD
Date reviewed: January 2006
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
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