From: "Steve Harris" <sbharris@ix.RETICULATEDOBJECTcom.com>
Newsgroups: sci.life-extension,alt.health,sci.med,misc.health.alternative
Subject: Re: Water-Drinking Myth?
Date: Fri, 9 Aug 2002 19:18:21 -0600
Message-ID: <aj1pup$vt3$1@slb4.atl.mindspring.net>

"Ian Goddard" <igoddard@erols.mom> wrote in message
news:3d544fe6.351868923@news.erols.com...
> http://www.dartmouth.edu/dms/news/2002_h2/08aug2002_water.shtml
>
> Dartmouth Medical School
>
> 'Drink at least 8 glasses of water a day' -- Really?
>
> Dartmouth professor finds no scientific evidence for '8 x 8'
>
> Hanover, NH -- It has become accepted wisdom: "Drink at least eight
> glasses of water a day!" Not necessarily, says a DMS physician Heinz
> Valtin, MD. The universal advice that has made guzzling water a
> national pastime is more urban myth than medical dogma and appears
> to lack scientific proof, he found.
>
> In an invited review published online by the American Journal of
> Physiology August 8, Valtin, professor emeritus of physiology at
> Dartmouth Medical School, reports no supporting evidence to back
> this popular counsel, commonly known as "8 x 8" (for eight,
> eight-ounce glasses). The review will also appear in a later issue
> of the journal.
>
> Valtin, a kidney specialist and author of two widely used textbooks
> on the kidney and water balance, sought to find the origin of this
> dictum and to examine the scientific evidence, if any, that might
> support it. He observes that we see the exhortation everywhere: from
> health writers, nutritionists, even physicians. Valtin doubts its
> validity. Indeed, he finds it, "difficult to believe that evolution
> left us with a chronic water deficit that needs to be compensated by
> forcing a high fluid intake."
>
> The 8 x 8 rule is slavishly followed. Everywhere, people carry
> bottles of water, constantly sipping from them; it is acceptable to
> drink water anywhere, anytime. A pamphlet distributed at one
> southern California university even counsels its students to "carry
> a water bottle with you. Drink often while sitting in class..."


Bravo. Though I hear people like Karl Loren and Dr. F. Batmanghelidj
screaming away in the background, I certainly agree and you'll never find me
recommending this 8 glass a day nonsense. There's all kinds of evidence that
humans are still basically savannah mammals. We can take huge amounts of
heat, and we have really good water conservation and urine concentration
abilities for mammals (the cat family does as well, but they're basically
desert animals also). We just don't need as much water as that, except in
very special conditions where we have to sweat a lot.

The minimum amount of urine a white collar adult has to make is more like 3
glasses a day. So anything above 4 in temperate conditions for
semi-sedentary people, is gravy. So unless you're sweating like a pig or the
temperatures and humidities are very high and unlike anything you're used to
(ie, you're being subjected to unusual conditions for you), you can drink
when you're thirsty. Don't worry about it.

Having said that, the thirst mechanism does go awry in some small subset of
elderly people. But making recommendations for everybody because of THEM,
would be very wasteful.

SBH

From: "Steve Harris" <sbharris@ix.RETICULATEDOBJECTcom.com>
Newsgroups: sci.life-extension,alt.health,sci.med,misc.health.alternative
Subject: Re: Water-Drinking Myth?
Date: Fri, 9 Aug 2002 22:43:31 -0600
Message-ID: <aj25vg$ejg$1@slb4.atl.mindspring.net>

"mike" <emkaypee@dodgenet.com> wrote in message
news:aj1vu3$esl$4@ins22.netins.net...
> igoddard@erols.mom (Ian Goddard) wrote:
>
> >How did the obsession start? Is there any scientific evidence that
> >supports the recommendation?
>
> Maybe excessive water consumption and subsequently polyuria are controls
> for blood sugar level? Then we could implicate an insulin link:
> http://www.sciam.com/article.cfm?articleID=00019760-09C1-1C5E-B882809EC588
> ED9F&pageNumber=1&catID=1
>
> Effect on the postprandial glycaemic level of the addition of water to a
> meal ingested by healthy subjects and type 2 (non-insulin-dependent)
> diabetic patients.
> Torsdottir I, Andersson H.
> Department of Clinical Nutrition, University of Goteborg, Sahlgren's
> Hospital, Sweden.
>
> http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_
> uids=2759361&dopt=Abstract
>
> Just an idea.Type 2 diabetics have increased thirst and pee more.This
> is an adaptive response to control excess blood sugar.Does it work the
> same in nondiabetics? Got me.


Glucose in the blood above renal pump theshholds is an osmotic diuretic--
this has nothing to do with insulin. It's just a simple effect of high blood
sugars on the kidneys.
Far from controlling excess blood sugar, this process generally makes it
worse, since you lose water faster than sugar, and you have to drink like
mad to keep up with the water loss.

In type II diabetes it's true you can generally hold your blood sugar down
to medium high (somewhere between normal and sky high) this way so long as
you're conscious-- but get behind at all, and you dehydrate, and then your
sugars go WAY up. That's basically what puts untreated type II diabetics in
coma-- dehydration.

SBH

From: Steve Harris <sbharris@ix.netcom.com>
Newsgroups: sci.med.nutrition
Subject: Re: Is there a limit to how much water you should drink per day?
Date: 5 Sep 2005 23:01:00 -0700
Message-ID: <1125983697.089446.118020@g43g2000cwa.googlegroups.com>

timbo wrote:
> I've been reading that 2.5L of water per day is the minimum required.
> And if you drink tea or coffee or any diuretics then you should
> increase the water intake.
> So this raises the question above.
> The other question is, is there any risk of all this water stressing &
> over-working the kidneys?
> What are the benefits of drinking lots of water other than weight loss?
> Also how is it known that 2-2.5 litres is the what's needed?
> How & when did this research come about?
>
> T.


COMMENT:

Most of the recommendations for water consumption are urban myths.
Kidneys actually work harder to KEEP water, so drinking more puts less
stress on them. But the difference isn't worth mentioning.

The average person can get along on 1 L of urine output (about a quart
a day), or less. Depending on climate and water loss from sweating, of
course, you may have to drink the difference. That can be a few hundred
mL to many liters more.  It's hard to generalize.

Drinking a lot of water doesn't make you lose weight. There may be some
slight effect of distending your stomach with water before you eat, but
that balances out eventually, too, and you will just be more likely to
develop an expanded stomach and hiatal hernia, in order to get the
calories your body thinks you need. A dumb way to go. Save your stomach
from reflux, and graze.

People with renal stones could almost always benefit from more fluids
than they're used to, to dilute the urine more than it was when they
developed the stones. As for the rest of us, drink when you're thirsty.
Humans evolved in the dry savannah country of East Africa. We do fine
on a lot less water than a lot of us drink, and a lot less than the
health nuts think we should drink.

SBH

From: Steve Harris <sbharris@ix.netcom.com>
Newsgroups: sci.med.nutrition
Subject: Re: Is there a limit to how much water you should drink per day?
Date: 6 Sep 2005 15:04:15 -0700
Message-ID: <1126044255.151717.159460@g44g2000cwa.googlegroups.com>

Mirek Fidler wrote:
> No. Anyway, there is a danger associated with drinking TOO much of PURE
> water as it depletes your blood electrolytes. But I guess this would
> happen at more than 5L / day or something like that.
>
> Mirek


Baloney. You get all your electrolytes in your diet, and can safe drink
distilled water if you like (though it's an unneeded expense). Your
body is perfectly capable of peeing off 5 or even 10 L of water a day,
while keeping all the other stuff it needs.

From: Steve Harris <sbharris@ix.netcom.com>
Newsgroups: sci.med.nutrition
Subject: Re: Is there a limit to how much water you should drink per day?
Date: 6 Sep 2005 20:36:12 -0700
Message-ID: <1126064171.968868.169930@g47g2000cwa.googlegroups.com>

Mr-Natural-Health wrote:
> Steve Harris wrote:
>
> > Mirek Fidler wrote:
> > > No. Anyway, there is a danger associated with drinking TOO much of PURE
> > > water as it depletes your blood electrolytes. But I guess this would
> > > happen at more than 5L / day or something like that.
> >
> > Baloney. You get all your electrolytes in your diet, and can safe drink
> > distilled water if you like (though it's an unneeded expense). Your
> > body is perfectly capable of peeing off 5 or even 10 L of water a day,
> > while keeping all the other stuff it needs.
>
> Baloney!
>
> Marathon runners are dying all the time from drinking too much water
> during a run.
>
> So, you are an Arse.  Just thought that you might want to know.


They're under a lot of stress, often salt-depleted, and don't work up
to it. The average pair of kidneys can put out up to 10 L a day.

5 L is a bit less than 9 pints of British beer. You can see that down
in any pub on a weekend.

SBH

From: Steve Harris <sbharris@ix.netcom.com>
Newsgroups: sci.med.nutrition
Subject: Re: Make your drinking Water Healthy
Date: 23 Aug 2005 11:57:20 -0700
Message-ID: <1124823440.284818.38700@g44g2000cwa.googlegroups.com>

teeseari...@yahoo.com wrote:
> Your Body Is 70% Water!


Not unless you are a newborn baby. Or a very, very, very skinny male.

The average is more like 60% if you're a man, and 50% if you're a
woman.

SBH