How Much Water Do I Need?
Everywhere I travel I see people carrying lots of water. I am frequently
asked: “I drink 8 glasses of water a day. Is this enough?” It is more
than enough and is often too much – to the point of being detrimental to
your health! Here are the highpoints of a recent news article.
Experts challenge myths about water consumption, Benedict Carey, Los
Angeles Times, Dec. 18, 2000.
Talk about a drinking problem.
On the one hand, it seems that more
people than ever are drinking heavily: College students bring bottles
into classrooms; office workers nip from jugs all day long. Many of us
are like Gerri Johnson, a 56-year-old kindergarten teacher living in
Manhattan Beach, Calif., who says, “I carry a bottle of water throughout
the day, and I'm always drinking. It flushes out my body, and it's good
for my skin.”
At the same time, some nutritionists insist that half the country is
walking around dehydrated. We drink too much coffee, tea and sodas
containing caffeine, which prompts the body to lose water, they say; and
when we are dehydrated, we don't know enough to drink.
Can it be so? Should healthy adults
really be stalking the water cooler to protect themselves from creeping
dehydration?
Not at all, doctors say. "The notion that there is widespread
dehydration has no basis in medical fact," says Dr. Robert Alpern,
dean of the medical school at the University of Texas
Southwestern Medical Center in Dallas.
Doctors from a wide range of specialties agree: By all evidence,
we are a well-hydrated nation. Furthermore, they say, the
current infatuation with water as an all-purpose health potion — tonic
for the skin, key to weight loss — is a blend of fashion and fiction
and very little science.
Consider that first commandment of good health: Drink at least eight
8-ounce glasses of water a day. This unquestioned rule
is itself a question mark. Most nutritionists have no idea where it
comes from. "I can't even tell you that," says Barbara Rolls, a
nutrition researcher at Pennsylvania State University, "and I've written
a book on water."
Some say the number was derived from fluid intake measurements taken
decades ago among hospital patients on IVs; others say it's less a
measure of what people need than a convenient reference point,
especially for those who are prone to dehydration, such as many elderly
people.
Kidney specialists do agree on one thing, however: that the 8-by-8
rule is a gross overestimate of any required minimum. To replace
daily losses of water, an average-sized adult with healthy kidneys
sitting in a temperate climate needs no more than one liter [One
liter is the equivalent of about four 8-ounce glasses] of fluid,
according to Jurgen Schnermann, a kidney physiologist at the National
Institutes of Health.
According to most estimates, that's roughly the amount of water most
Americans get in solid food. In short, though doctors don't recommend
it, many of us could cover our bare-minimum daily water needs without
drinking anything during the day.
The way it's almost always stated, in books, magazines and newspapers,
the 8-by-8 rule specifically discounts caffeinated beverages. This is
flat wrong. Caffeine does cause a loss of water, but only a fraction
of what you're adding by drinking the beverage. In people who don't
regularly consume caffeine, for example, researchers say that a cup of
java actually adds about two-thirds the amount of hydrating fluid that's
in a cup of water.
Regular coffee and tea drinkers become accustomed to caffeine and lose
little, if any, fluid. In a study published in the October issue of the
Journal of the American College of Nutrition, researchers at the
Center for Human Nutrition in Omaha, Neb, measured how different
combinations of water, coffee and caffeinated sodas affected the
hydration status of 18 healthy adults who drink caffeinated beverages
routinely.
"We found no significant differences at all," says nutritionist Ann
Grandjean, the study's lead author. "The purpose of the study was to
find out if caffeine is dehydrating in healthy people who are
drinking normal amounts of it. It is not."
The same goes for tea, juice, milk and caffeinated sodas: One glass
provides about the same amount of hydrating fluid as a glass of water.
The only common drinks that produce a net loss of fluids are those
containing alcohol — and usually it takes more than one of those to
cause noticeable dehydration, doctors say.
Now, take a close look at a survey released this May by the
International Bottled Water Association. Based on interviews with 2,818
adults in 14 U.S. cities, the association concluded that "although an
overwhelming majority of Americans know that drinking water enhances
health, most don't drink as much per day as they should."
Yet, according to the association's own numbers, Americans say they
drink an average of 6.1 glasses of water, 3.7 servings of soda or sports
drinks, 3.2 of coffee and tea, 1.9 of juice, 1.7 of milk, and one
alcoholic drink each day.
All told, after subtracting the alcoholic drink, that's a sopping 15
glasses of hydrating fluids, well above the already exaggerated
"minimum." And it doesn't even include the three or four glasses
contained in solid food.
In addition, researchers have good evidence that people who develop
kidney stones can lower their risk of further problems by drinking more
fluids. "Those are the only patients we would tell to drink more
water," Alpern says.
Of course, if you're healthy, and you're laboring over the stair
machine, playing basketball, or even gardening in a hot, dry climate,
you're going to need a lot more than a liter to keep you hydrated. But
you hardly need a nutritionist or a doctor to tell you that.
"You're dying of thirst," Alpern says. "The thirst mechanism
is one of the most powerful and sensitive of all the
body's regulatory processes."
Robertson says that this mechanism almost
always kicks in when we've lost between 1 percent and 2 percent of body
water.
"There's no evidence that this 1 to 2 percent decrease is harmful in any
way," he says. "Thus, there is really no need to `prevent' this slight
decrease in body water by drinking a specified amount in the absence of
thirst."
What if you're sweating and, for some
reason, don't or can't drink? That's when the body will begin to squeeze
water from its own tissues, including the brain and the skin. And that's
why you may get a headache when dehydrated, and why your skin can look
ragged and dry. A tall, cool glass of water or soda or iced tea will
soothe your head and revive your skin, in most cases, doctors say — but
only if you're dehydrated to start with.
"If you're a normally hydrated person, like you or me," says Dr. David
Rish, a dermatologist in Beverly Hills, Calif., "then drinking extra
water is not going to do anything for your skin. If your skin
is dry, and you're hydrated, the best thing to do is apply lotion."
Perhaps most cruelly of all, there's no good evidence that drinking
water significantly curbs appetite.
"I think that's mostly an invention of the diet industry," says
Carolyn Katzin, a nutritionist in Los Angeles who runs the American
Cancer Society's nutrition program in California. ….
Life-Systems Engineering analysis: It was delightful to
read an article published in a popular media that was based on science.
The bottom line: Most of us get all the water we need from food.
Drink if you are thirsty, and never “force-feed” yourself
excess water. The body’s automatic thirst response kicks in before
you physiologically require more water. I have seen “guessperts”
claim that, when you are thirsty, it’s too late. Physiologically,
nothing could be further from the truth!
The admonition, “Drink lots of water” is promoted by the water industry
and the nutrition industry in the hopes that your stomach will expand
and you will feel full. This fallacy results from neglecting the
insulin response. When overdosing on water, your body responds as
though food has entered your stomach and secretes insulin to digest it.
Insulin makes you hungry. That’s why the “drinking lots of water”
method doesn’t work for appetite suppression or fulfillment – it
is a very temporary effect.
Overdosing on water dilutes your blood, too. This causes a systemic
imbalance and raises havoc with your body’s automatic life-systems. Is
your physician or nutritionist basing his recommendations on science or
opinion? If it’s opinion, then it’s time you learned about Radiant
Health.