From: sbharris@ix.netcom.com (Steve Harris  sbharris@ROMAN9.netcom.com)
Newsgroups: misc.health.alternative
Subject: Re: Magnesium Citrate
Date: 16 Oct 2004 18:35:46 -0700
Message-ID: <79cf0a8.0410161735.72e10c9c@posting.google.com>

"Gymmy Bob" <nospamming@bite.me> wrote in message
news:<TpmdnQfW05D7Au3cRVn-2A@golden.net>...

> Mag citrate is an acidic form of magnesium and probably contradicts any
> health benefits you will get out of it by making your system acidic.


COMMENT:

Baloney! Learn some physiology! Metal citrate salts are salts-- they
are neutral not acidic. And like lactate salts, metal citrate salts
are metabolized to bicarbonate, which makes the body alkalotic, not
acidic. Citrate and lactate salts have long been used to *alkalinize*
the urine for this reason. Magnesium citrate will have the same
effect.

Lactic acid and citric acid (the acids themselves, not their salts)
effectively do not present the body with any acid load,, any more than
carbonic acid does. That is because they can all be completely
metabolized to CO2 and water, and the CO2 is breathed away without
affecting the urine. However, this is not true of the metalic salts of
these acids, which can obviously be metabolized to bicarbonate ion,
but no further.

http://www.drugs.com/MMX/Sodium_Citrate_and_Citric_Acid.html


> Try magnesium, chelated. Mag oxide gave me bone spurs in both feet and many
> spots. The other health benefits were wonderful.


COMMENT:

Any magnesium salt that is soluble will do. The oxide and the
hydroxide are indeed relatively poorly absorbed (generally due to the
fact that except in small doses, few people make enough acid at single
meals to completely convert more than a few hundred milligrams of
magnesium oxide or hydroxide to the free soluble Mg++ ion (equivalent
to what you get in MgCl2). There is no evidence that chelates are
absorbed any better than magnesium chloride or lactate. Buy what's
cheapest per milligram of Mg.


> The RDA for magnesium is 420 mg. This is the minimum daily intake to barely
> sustain life without disease.


That's not how RDA's were historically arrived at (or DRI's either).



> This is also the measurement of the elemental
> requirements. I doubt 10Kg of mag oxide would give you this amount.


Well, you doubt wrong. Studies show perhaps 4% absorption of Mg from
MgO. It's up around 20% for other salts, so you do the math.

SBH

From: sbharris@ix.netcom.com (Steve Harris  sbharris@ROMAN9.netcom.com)
Newsgroups: misc.health.alternative
Subject: Re: Magnesium Citrate
Date: 17 Oct 2004 19:57:58 -0700
Message-ID: <79cf0a8.0410171857.36fe8de0@posting.google.com>

Peter Meiers <Tren_Dean@yahoo.com> wrote in message
news:<417228EB.6D94@yahoo.com>...

> Steve Harris sbharris@ROMAN9.netcom.com wrote:
>
> > Baloney! Learn some physiology! Metal citrate salts are salts-- they
> > are neutral not acidic.
>
> WRONG. They are neutral with respect to electric charges, but in
> solution they may very well be acidic (depending on the type of metal
> ion). What happens once they are metabolized is quite another question.
>
> Peter



COMMENT:

"Neutral" here should be understood as an approximation, for all but
salts of the very strongest acids and bases combined.  But it's a
pretty good approximation for the kinds of salts we're talking about.
They might be slightly basic, but not enough to be caustic. The pHs of
tribasic citrate salts run about 9.

And no, soluble metal salts of acids are not going to be acidic in any
case I I can think of. They are (mildly) basic if the conjugate acid
is not a very strong acid. Citric acid has three protons, and the pKa
of the last one is sufficiently high to make tribasic citrate salts
somewhat basic.

You can calculate it. The last (and controlling) pKa of citrate is 5.2
so the associated pKb = Kw- ka = 8.8. So [OH-]^2/[citrate] = 10^-8.8.
If you put in 1 molar citrate just for example, you get the pOH =
8.8/2 = 4.4, so the pH comes out 14-4.4 = 9.6. That's alkaline, but
(again) not enough to be caustic. For 0.1 M tribasic citrate you can
see pH = 14 - [9.8/2] =  9.1. And so on, with the pH dropping half a
point for every log in tribasic citrate concentration.

SBH

From: sbharris@ix.netcom.com (Steve Harris  sbharris@ROMAN9.netcom.com)
Newsgroups: misc.health.alternative
Subject: Re: Magnesium Citrate
Date: 18 Oct 2004 12:00:45 -0700
Message-ID: <79cf0a8.0410181100.4b792eba@posting.google.com>

Peter Meiers <Tren_Dean@yahoo.com> wrote in message
news:<41734A8B.315B@yahoo.com>...

> Steve Harris sbharris@ROMAN9.netcom.com wrote:
>
> > And no, soluble metal salts of acids are not going to be acidic in any
> > case I I can think of.
>
> Ever prepared a phosphate buffer? Mixture of an acidic with a basic
> phosphate.
> Just an example.


COMMENT: Not an example, because phosphate buffers are not metal salts
of acids. They are are only partial metal salts of acids, with some of
the acid left. In any buffer the acid has only been *partly*
neutralized, and therefore of course the result may still be acidic.
That's not what we were talking about with magnesium citrate.

If you neutralize phosphoric acid it all the way to (tribasic) sodium
phosphate, or for that matter all the way to tribasic magnesium
phosphate, you'd get something extremely alkaline. The last pKa for
phosphoric acid is 12.7, and if you put that through my equation above
you get a pH for 1 M Na3PO4 of 13.35. That's VERY alkaline.

And yes, FYI, I've prepared many a phosphate buffer. And knew what I
was doing, too <g>.

SBH