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From: ((Steven B. Harris))
Subject: Re: Acid/Alkaline Balan, Aging, and Disease
Date: 09 May 1995

In <3olnor$> (Temple)

>> >Acids were not available for ingestion until the discovery of
>> >fermentation. I don't think that the kidneys could be said to have
>> >evolved in that short a time.

I answer:

>> Until the discovery of fermentation! Primates have been eating
>> fermented fruit for as long as there have been primates. That's WHY we
>> have an alchohol dehydrogenase enzyme, don't you know. And in any case,
>> the largest acid loads in the diet are from metabolism of protein, and
>> have nothing to do with fermentation. Alcohol does not present an
>> effective acid load to the body, because it can be metabolized
>> completely to CO2 and H2O, and needs no renal acid excretion.
>I wasn't referring to alcohol, but to vinegar.

Comment: the same goes for vinegar.  Acetic acid is completely
metabolized and presents no net acid load to the body, because it's all
changed to CO2 and H2O.  You can have some on your salad and your urine
pH won't change a whit.

   This is true of most organic acids, by the way.  You can be acidotic
after a long run from the lactic acid made in your muscles, but it
disappears as you metabolize it, not because your kidneys get rid of it.
Your kidneys' problem is inorganic acids, like the sulfuric acid you
make from digesting protein.  And, to some extent, phosphoric as well.

                                        Steve Harris, M.D.

From: B. Harris)
Subject: Re: DEMINERALISATION symptoms
Date: 23 Aug 1996

In <> Will White <> writes:

> Common sense tells you that casein causes the kidneys to tap
>bone-calcium to maintain the blood's acid-base balance? Hmmm. . .you have
>uncommon common sense then. All refs are not equal. That is why sources
>are cited. Both in quantity and quality, a review of available literature
>will yield a clearer picture of what goes on. And one needn't have a
>Ph.D. to evaluate research and epidemiological data. Just a critical,
>literate mind. I'm puzzled buy how casein per se might influence the
>acid-base balance. Which amino acid present in casein taxes the kidneys
>so much, as casein itself never makes it intact into the blood stream?
>I'd really like to know, because the amino acid content of different
>dairy products is substantially different, especially when milk is
>compared to cheese and yogurt. Also, what chemically occurs in the
>pasteurization process that is harmful. I am not disagreeing with you to
>be provocative, I genuinely want to understand this issue. And I like
>milk, and cheese, and yogurt!
>> As people get older, most can't break milk down, especially isolating
>>the calcium and the sugars. If I have to dig up references on this type
>>of statement, in a forum like this loading with PhD's and the like who
>>have doubtless seen this statement thousands of times, then I am in the
>>wrong place. We just don't have the level of enzymes anymore, even if
>>you are one of the lucky ones who still can handle milk without "lactic
>>problems". As a result, you get increased acidic conditions, your
>>stomach working madder and madder to break it down. This draws calcium
>>from the blood to reduce the acidity levels afterwords. Casien doesn't
>>break down very well in acid -- it needs specific enzymes.
> I'm confused. Do the kidneys regulate stomach acidity? My understanding
>of the acidity problem and calcium loss has to do with the acid-base
>balance in the *blood*. The progressive difficulty in dairy digestibility
>would seem to have more to do with a more basic stomach environment, as
>we produce less HCL. Moreover, calcium is itself basic, isn't it? That is
>why the kidneys use it to regulate acidity in the *blood*.
>--Will White

   Hmmm, there seems to be quite a bit of confusion here.  Acid made in
your stomach doesn't count in your overall balance of acid-base,
because it must be balanced by base made somewhere else in the body.
Eventually, the two neutralize each other (as when stomach acid comes
into contact with alkaline pancreatic juice), and it is as though the
acid had never been made.

   What puts a "strain" on the body is EATING acids.  And eating things
which are metabolized into acids.  Bases can simply be passed into the
urine as is.  Examples are metal lactate and citrate salts, which are
metabolized into bicarbonate, which either neutralizes urine acid, or
is excreted directly as alkaline urine.  Urine inorganic acid comes
basically from dietary phosphoric acid (soft drinks and nucleic acid
breakdown), and also from sulfur-containing amino acids in the diet
which are metabolized to sulfuric acid.  You cannot excrete much
sulfuric and phosphoric acid directly in the urine, or it would burn
you!  Therefore the body has to neutralize it and get that pH up.
That's where your bones come in-- they disolve like basic chalk in
acids, and the resulting calcium salts go out in the urine.  If you
don't eat enough calcium and magnesium and organic basic or base-making
substances (carbonate, lactate, citrate), you're going to lose bone in
maintaining your urine buffer.  Urine is normally acidic due to the
proteins and phosphate containing stuff (DNA and RNA) we eat.  But not
too acidic.

   As for casein, I think it's a pretty ordinary protein.  It's a bit
short on methionine, but has plenty of sulfur as cysteine.  It would
surprise me if it's all that much worse load on your calcium stores
than other proteins.  The stuff you've been hearing here about specific
problems digesting casein is so much hooey.  If you can digest soy
protein, you can digest casein.

                                       Steve Harris, M.D.

From: B. Harris)
Subject: Re: vitamin-C ? ? ?
Date: Thu, 23 Oct 1997
Newsgroups: wrote:

     >> Here is the deal:  any "weak acid", which is what aspirin and
Vit C are, does not and CANNOT act like an acid in the stomach!!  Why?
Because the stomach is FILLED with almost pure HCl (pH 2 or lower)!!!
You can do the calculations and show that a pound of C dumped in the
stomach will not change the pH!  And the duodenum/small intestine is
alkaline or the express purpose of neutralizing the acidic effluent
from the stomach. So there is almost no point to buffering a slightly
acidic compound. And related to this, there is almost no point to any
of the acid neutralizers, either, since they just make the
acid-producing cells produce more acid! <<

   "Physical@erols" here demonstrates a lack of basic knowledge of
physiology, although his chemistry is sound.  Every bit of acid in your
stomach must be matched by a bit of base made when the proton is pumped
in by the parietal cells.  So far as the overall acid/base status of
your body is concerned, stomach acid doesn't "count."  It's matched by
alkaline pancreatic juice, and the two neutralize each other again in
the duodenum.  You may have a lot of stomach acid, but it's all spoken
for.  Acid/base wise, it's all borrowed money.

   Acid or base loads from the outside DO count, for they must be
neutralized by something real (not borrowed, like stomach acid or
pancreatic juice base), and the result must show up in the urine.  Base
cannot just be done away with by stomach acid, for that acid is (again)
borrowed, and it leaves base behind somewhere else if it is destroyed
before the duodenum, still leaving your body with base excess.   The
body deals with base excess quite easily, however, as most bases
contain metal ions, and the body can excrete these directly, along with
bicarbonate in the urine, to get rid of metal/bicarbonate base loads.
In short, if you eat sodium bicarbonate, you can pee sodium
bicarbonate.  By contrast, it's a lot harder to pee calcium carbonate
or bicarbonate, because it's insoluable, so if you eat enough of this
(or bicarbonate with calcium) to exceed your body's normal acid-load
buffering requirements, you CAN get into trouble (see the "milk-alkali

   Acids are an even more difficult matter, for they often are offered
with no metal ions.  If they are strong acids like HCl from betaine
HCl, or sulfuric acid from protein metabolism, or phosphoric acid from
DNA metabolism or soft drinks, the body cannot simply dump them in the
urine, for this would lower the pH too much.  They must be buffered
with base, but the base cannot be bicarbonate because this takes a
metal cation, and unless a bicarbonate salt has been eaten, none is
available (all have a corresponding anion like chloride to get rid of,
and there is no way to DO that).  Generally the body's only solution in
such circumstances is to buffer the ingested or metabolic acid with the
calcium hydroxyappetite in bone, which is a base.  The result is
calcium loss in the urine.  Even comparatively mild acids like vitamin
C (in ascorbic acid form) will result in some increased calcium loss in
the urine, although a lot of free vitamin C as ascorbic acid can be
directly excreted, because its pH is not tremendously high.

                                        Steve Harris, M.D.

From: B. Harris)
Subject: Re: glutathione, cystine, methionine
Date: Fri, 24 Oct 1997

In <> writes:
> Again, methionine supplied strictly as a limiting amino acid should not
>cause all of this. You would have to exceed the buffering capacity of the
>blood to start leaching calcium (I would think). And the body has built
>in buffering mechanisms, not that they should be abused.[...] Finally,
>regarding methionine, I take your word for it that it generates H2SO4.
>Can you show me how? I would be surprised if this H2SO4 were not
>metabolically anticipated, so that blood buffering should never be
>utilized. I would suspect that this bone loss may very well occur in
>people with buffering problems!

For the metabolism of methionine see any good biochem text.

The buffering capacity of the blood has nothing to do with what calcium
you lose, for it represents neutralizing capacity which must be repaid,
if used. It's analogus to the owner of a small grocery store who
siphons off $10,000 from the till in year, thinking the money
insignificant by the side of the store's $1 million gross.  Alas, the
store opperates on a 3% profit margin, and the $10,000 comes out of
only $30,000 profit.  That's your body.  There are huge acid and base
reserves in there, but they balance each other more or less, and they
can't just be used willy nilly to neutralize outside acid and base

                                       Steve Harris, M.D.

From: B. Harris)
Subject: Re: glutathione, cystine, methionine
Date: Mon, 10 Nov 1997

In <Pine.OSF.3.96.971108211205.27339L-100000@willow> Bill Roberts
<> writes:

>On 6 Nov 1997, Steven B. Harris wrote:
>> <> writes:
>> > Do you think protein is an acid? The word "indeed" seems to imply
>> > that. If so it is not really correct.
>> Protein is metabolized to acid.
>As a generalization that is a false statement.

   No, as a generalization, this is a true statement.  Since all
proteins contain methionine, all proteins generate an acid load when

>If you had add accurate knowledge and the desire or ability to
>communicate precisely, you would have said that there are some
>acidic metabolites of protein.

    There are some acidic metabolites of ALL proteins.  Which gets us
back to what I said.

>> In particular, methionine is
>> metabolized to sulfuric acid, among other things.
>Oh my gosh, how absolutely awful. Do you actually think that this
>is harmful?

   It causes increased calcium loss, which is what I said.

>Perhaps you are unaware that in aqueous solution, all acids level
>to H30+. Con H2SO4 is one thing. Generation of sulfuric acid by
>metabolism is no big deal. If it were we'd all have big problems.
>But hey, it sounds scary, so you can use it to scare people! Great
>rhetorical technique to promote quack arguments, though.

    It only sounds like a "quack argument" because you know nothing
about the subject.

>Doc, the fact is that there is nothing dangerous about the urinary pH
of persons on high protein diets,<<

   No, there isn't.  That's because the acid has been neutralized by

>let alone blood pH, which, ruining your theory about acid leaching
>calcium from the bones, is the SAME as that of persons on low protein
>diets. Perhaps you have not heard about the H-K-ATPase pump. It really is
>not difficult for the body to excrete excess H+.

    Again, you know nothing of physiology.  The H-K-ATPase is a pump.
It doesn't make acid disappear into the 5th dimension.  You eat acid,
you have to get rid of it.  That takes a mineral buffer.

>> > Have you checked to see if calcium, phosphorus, and magnesium intake
>> > was the same between the low and high protein groups?
>>    Yes, these are controlled in the experiments.
>Name the study, then. Don't just assert that it exists.


Okay, here are two such studies.

J Nutr 1981 Feb;111(2):244-251
Long-term effects of level of protein intake on calcium metabolism in
young adult women.

Hegsted M, Linkswiler HM

The long-term effect of level of protein intake on calcium metabolism,
renal function and renal acid excretion was determined during a 75-day
metabolic study. Six women consumed a diet containing either 46 or 123
g protein for 60 days; they then consumed the alternate diet for 15
days. Calcium, phosphorus and magnesium intakes were maintained
constant at 500, 900 and 350 mg, respectively, throughout the 75-day
study. Urinary calcium was remarkably constant with time at both levels
of protein intake but was approximately twice as high when the 123 g
protein diet was consumed. Level of protein intake had
no effect on calcium absorption; the increase in urinary calcium found
when the high protein diet was given, therefore, caused a markedly
negative calcium balance. Glomerular filtration rate (GFR) and renal
acid excretion were higher and fractional renal tubular reabsorption of
calcium was lower when the high protein diet was given. The
hypercalciuria caused by the high protein intake was due primarily to
the decrease in fractional tubular reabsorption of calcium
and, to a lesser extent, to the increase in GFR. Neither GFR,
fractional renal tubular reabsorption of calcium nor any of the
components of renal acid excretion exhibited any tendency to change
with time over the 60-day experimental period.


Am J Clin Nutr 1981 Oct;34(10):2178-2186
Calcium metabolism in postmenopausal and osteoporotic women consuming
two levels of dietary protein.

Lutz J, Linkswiler HM

Eight postmenopausal women, four with osteoporosis diagnosed by their
physician and four without, participated in a metabolic study to
investigate the effects of level of protein intake on calcium
metabolism; renal acid excretion; plasma total and ultrafiltrable
calcium; 1,25-dihydroxyvitamin D; and serum immunoreactive parathyroid
hormone. Radial bone mineral content was evaluated. Protein intake was
50 g/day during the 1st 15-day experimental period and 110 g
during the 2nd period. Calcium, magnesium, and phosphorus intakes were
held constant at 713, 323, and 1078 mg/day. The increase in protein
intake significantly increased net calcium absorption and urinary
calcium. A calcium intake of 713 mg was not sufficient for calcium
balance for most of the women studied. The calciuretic effect of
increased protein intake was associated with increased renal acid
excretion. None of the plasma and serum measurements
mentioned above was significantly affected by the level of protein
intake except for a slight increase in plasma total calcium. No
significant differences in radial bone mineral content or in any of the
other measurements were observed between the osteoporotic and the
normal group of women.

And here is another similar study.  There are many more in the
literature.  Pay attention to the author conclusions.

Fed Proc 1981 Jul;40(9):2429-2433
Protein-induced hypercalciuria.

Linkswiler HM, Zemel MB, Hegsted M, Schuette S

Under controlled dietary conditions the level of dietary protein has a
profound and sustained effect on urinary calcium and calcium retention
of man. Young adults achieve calcium balance at low intakes of 500 mg
calcium and 700 to 1,000 mg phosphorus when protein intake is 50 g.
Large calcium losses occur at the same calcium and phosphorus intakes
when the protein intake is increased approximately threefold. The
protein-induced hypercalciuria is due mainly to a decrease in
fractional renal tubular reabsorption of calcium, although
an increase in glomerular filtration rate is also involved. The changes
in kidney function appear to result from the catabolism of excess
dietary sulfur amino acids to sulfate and the subsequent excretion of
sulfate in the urine. An increase in both protein and phosphorus
intakes has a much less dramatic effect on urinary calcium and calcium
retention than an increase in protein intake alone. An increase in
dietary phosphorus greatly reduces urinary calcium by increasing the
fractional renal tubular reabsorption of calcium. It appears
therefore that high protein intakes may increase the requirements for
both calcium and phosphorus.

>Don't forget that YOU are the one making a positive assertion here.
>You are saying that high protein diets cause loss of calcium. If you
>want your assertion to have any credibility, the burden is on you to
>support it. If you think your assertion has credibilty because you
>have an M.D. degree and therefore it should be accepted until I refute
>it, you have things quite backwards.

Okay, asshole.  The above studies are a start.  There are more,
however, if you want me to keep rubbing it in.  What I want to
know is why people with no training think they can make assertions like
yours without bothering to do the search time?  Is it an ego thing, or
just plain stupidity?  If an auto mechanic said something to me about
automobiles, I think I'd do some careful reading before calling him a
quack (or whatever) in public.  So what's your problem?  Too much
testosterone in your weight regimin?  Mother drop you on your head?
What?  Inquiring minds want to know.

>If you want to talk about not taking any brains, let me point out that
>it takes no brains to make the assertions that you have made.
>Absolutely none whatsoever. In fact, lack of brains would help a great

    So you say.  And you're the one who would know.   Next time you
call something a doctor says a "quack assertion," do your homework
first.  It will save you much embarassment.

                             Steve Harris, M.D.

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