How much water should you drink each day? — a simple
question with no simple answer. Various studies have
produced recommendations over the years, but in truth, your
water intake will depend on many factors, including where
you live, your health, and your activity level.

Health benefits of water

The health benefits are fairly well known and not very
profound. The human body is 55%-65% water, depending on
age, sex, and overall health. On average, women have less
water than men, and overweight people have less than thin
people (fat tissue contains less water than lean tissue).

So how much water do you need?

Every day you lose water through your breath, perspiration,
urine and bowel movements. For your body to function
properly, you must replenish its water supply by consuming
beverages and foods that contain water.

There are generally two approaches:

* Replacement: The average urine output for adults is 1.5
liters a day. You lose close to an additional liter of water
a day through breathing, sweating and bowel movements. Food
counts for about 20% of our daily fluid intake, so consuming
2 liters of water will typically replace lost fluids.

* Dietary recommendations. The Institute of Medicine advises
that men consume roughly 3.0 liters (about 13 cups) of total
beverages a day and women consume 2.2 liters (about 9 cups)
of total beverages a day.

It is generally the case that if you drink enough fluid so
that you rarely feel thirsty and produce between one and two
liters of colorless or slightly yellow urine a day, your
fluid intake is probably adequate.

Factors that influence water needs

Your total fluid intake may need to be modified depending on
how active you are, the climate you live in, your health
status, and if you're pregnant or breast-feeding.

* Exercise. The more you exercise, the more fluid you'll
need to keep your body hydrated. An extra cup or two of
water should suffice for short bouts of exercise, but during
long bouts of intense exercise, it's best to use a sports
drink that contains sodium, as this will help replace sodium
lost in sweat and reduce the chances of developing
hyponatremia, which can be life-threatening. Fluids should
also be replaced after exercise.

* Environment. Hot or humid weather can make you sweat and
requires additional intake of fluid. Heated indoor air also
can cause your skin to lose moisture during wintertime.

* Illness or health conditions. Signs of illnesses, such as
fever, vomiting and diarrhea, cause your body to lose
additional fluids. In these cases you should drink more
water and may even need a sports drink to replace lost
sodium.

* Pregnancy or breast-feeding. Women who are expecting or
breast-feeding need additional fluids to stay hydrated.
Large amounts of fluid are lost especially when nursing.

Dehydration and complications

Failing to take in more water than your body uses can lead
to dehydration. Even mild dehydration can sap your energy
and make you tired. Common causes of dehydration include
strenuous activity, excessive sweating, vomiting and
diarrhea.

Signs and symptoms of dehydration include:

* Mild to excessive thirst * Fatigue * Headache
* Dry mouth * Little or no urination * Muscle
weakness * Dizziness * Lightheadedness

Mild dehydration rarely results in complications — as long
as the fluid is replaced quickly — but more-severe cases can
be life-threatening, especially in the very young and the
elderly.

Staying safely hydrated

It's generally not a good idea to use thirst alone as a
guide for when to drink. By the time one becomes thirsty, it
is possible to already be slightly dehydrated.

To ward off dehydration and make sure your body has the
fluids it needs. Nearly every healthy adult can consider
the following:

* Drink a glass of water with each meal and between each
meal. * Hydrate before, during and after exercise. *
Substitute sparkling water for alcoholic drinks at social
gatherings.

If you drink water from a bottle, thoroughly clean or
replace the bottle often. Refill only bottles that are
designed for reuse.

Can you drink too much water?

Though uncommon, it is possible to drink too much water.
When your kidneys are unable to excrete the excess water,
the electrolyte (mineral) content of the blood is diluted,
resulting in a condition called hyponatremia (low sodium
levels in the blood). Endurance athletes who drink large
amounts of water are at higher risk of hyponatremia. In
general, though, drinking too much water is rare in healthy
adults who consume an average American diet.

If you're concerned about your fluid intake, check with your
doctor or a registered dietitian. He or she can help you
determine the amount of water that's best for you.

RESOURCE BOX: Linda Symonds grew up on a small island in
rural Canada where she developed a love of the natural
world. Linda believes that the polluted and toxic
environment that we live in poses significant risks to our
health and the health of coming generations. For more
information about the plight of our water supply visit
http://www.thebestwaterfilters.com