From: kja@cbnewsf.cb.att.com (krista.j.anderson)
Subject: Re: Quitting milk, another reason (was: winning argument w/meat eater)
Organization: AT&T
Date: Fri, 28 Aug 1992 22:32:55 GMT

In article <1992Aug26.181926.1918@drycas.club.cc.cmu.edu>, red_trek@drycas.club.cc.cmu.edu writes:
> 1)  The kind of calcium present in milk is apparently not in the 
> best form for your body to absorb it anyway (I'm not clear on this,
> someone please follow up to this and add more info:  is it something
> to do with the lactose and the fact that 3/4's of the population
> can't absorb lactose?  What the heck does lactose have to do with
> calcium?!!).

I checked out a book about calcium and it has the following chart: 

         Calcium Interactions
Nutrient     Effect        Why
fiber          negative     decreases intestinal absorption of Ca
protein        negative     increases urinary loss of Ca
caffeine       negative     incr. urinary and intestinal loss
sodium         negative     incr. urinary loss
phosphorus     neutral      decr. urinary loss, incr. intestinal loss
certain sugars positive     incr. intestinal absorption

Conclusions are that people on high-fiber diets need more calcium
as do people on high-protein diets.  The protein interaction is due
to the by-products of breaking down proteins that are not needed
for tissue replacement, i.e. excess protein.  "One of those
breakdown products is sulfuric acid, which draws some calcium out
with it when it is eliminated by the kidney."

Eating twice the recommended protein leads to a 50% increase in
urinary calcium loss.

     Thus, if a 120-pound woman were to increase her protein intake
     from 44 to 88 grams per day (not an unusual intake in the
     United States), her urine calcium loss would increase by about
     50-60 milligrams.  If her calcium absorption efficiency were
     in the range of 25-30 percent (as it commonly is in
     middle-aged women), she would have to increase her calcium
     intake by about 200-300 milligrams (equivalent to nearly an
     extra glass of milk each day)...

The story on certain sugars, namely lactose, is that it aids Ca
absorption in certain lab animals.  However, the authors feel that
the affect of sugars on Ca absorption in humans "makes little
difference".  They also have the point of view that eating should
be fun and worrying about excruciating details, like the fact that
spinach has calcium-binding oxalate, is not recommended.

The authors also feel that the interactions with phosphorus are
also not terribly important.  They site an FDA study in 1981 that
concluded that reported calcium deficiencies were not due to the
phosphorus in soda pop, but due to the fact that the soda pop was
being substituted for calcium-containing beverages like tap water.

Finally, they defend low-fat dairy products as good food.  My
irritation with vegans who bad-rap dairy products is mainly because
of my personal tastes; I get some of my few pleasures in life from
milk and cheese.

****If there are problems with the dairy and egg industries, I'd
rather work toward making those industries less cruel to animals
instead of boycotting their products.**** 

Reference
_Calcium and Common Sense_ by Robert P. Heaney, MD and M. Janet
Barger-Lux, NY:Doubleday, 1988.