NetNews Usenet Archive 1992 #31/NN_1992_31.iso/spool/sci/med/nutritio/1704

Text File | 1992-12-30 | 6.5 KB | 144 lines

Newsgroups: sci.med.nutrition
Path: sparky!uunet!gatech!darwin.sura.net!tulane!wpg!russ
From: [e-mail] (Russell Lawrence)
Subject: Re: Calcium/Magnesium
Message-ID: <[e-mail]>
Organization: WP Group
References: <[e-mail]>
Date: Thu, 31 Dec 1992 01:57:58 GMT
Lines: 133

From article <[e-mail]>, by [e-mail] (Steve Dyer):
> In article <[e-mail]> [e-mail] (Russell Lawrence) writes:
>>This sounds familiar.  Several weeks ago you stated that the
>>claim made by Ornish, Breslau, Marsh, Johnson, Allen (and many
>>others) concerning the impact of protein intake on calcium
>>excretion was "controversial at best"...  thereby implying that
>>"mainstream" opinion was on your side (as usual).  For some
>>strange reason, however, you failed to present any evidence to
>>support your side of the argument.
>
> Ornish doesn't make this claim other than to accept it at face value.

Let's permit Dr. Ornish to speak for himself:

"The real cause of osteoporosis in this country is not
insufficient calcium intake, it's excessive excretion of calcium in
the urine.  Even calcium supplementation is often not enough to
make up for the increased calcium excretion.  Vegetarians, in
contrast, excrete much less calcium, and this is why they have very
low rates of osteoporosis even though their dietary intake of
calcium is lower than those on a meat-eating diet.  See Ornish,
Dean.  _Reversing Heart Disease_.  Random House (Ballantine Books):
NY, 1990, p 301.

In the following text and footnotes, Ornish presents some of the
evidence supporting his claim that protein intake (especially
animal protein) increases calcium excretion.

What sort of evidence do you have to support your notion that Ornish
had "accepted [claim x] at face value" without critical scrutiny?

> His interests are in diet, blood lipids and atherosclerosis, and not
> osteoporosis, and he's done no research in this area.

It's encouraging that you haven't simply dismissed Ornish as a
"krank", although this may have something to do with Ornish's clout at
Harvard Medical School.  Still, it seems to me that you're attempting
to demean his opinion in order to enhance your own.

What standards are you using to define Ornish's "interests"?
Please explain, so that we may test Steve Dyer's "interests",
Steve Dyer's "research", and Steve Dyer's "face-value opinions"
using the same critical standards that Steve Dyer uses to test
other individuals.

> In fact, I did
> reply to your article, and gave you several references which refuted
> this claimed link between protein intake and calcium excretion.  Did
> you miss them?  I'll try to dig them up again.

If you posted "several references", as you say, I certainly did miss
them.  Please post them again.  Make sure you include a sufficient
number of pointers to support your claim that the relationship between
protein intake and calcium excretion is "controversial at best".   One
wishy-washy reference won't cut it.

Did you bother reading any of the papers that I mentioned in our
previous discussion.  If not, how can you be sure that the
underlying research was or wasn't conducted under controlled
conditions?  Here are two of the studies specifically cited by
Ornish:

==================================================================
Breslau et al.  "Relationship of animal protein-rich diet to
kidney stone formation".  _Journal of Clinical Endocrinology
and Metabolism_. 1988, pp 140-146.

Marsh et al.  "Vegetarian lifestyle and bone mineral density".
_American Journal of Clinical Nutrition_.  1988, pp 837-841.
==================================================================

>>I won't bother to ask you again for your references, but I wonder if
>>you'd mind telling us how the "mainstream" opinion against Moon's
>>"crank" hypothesis stacks up against the "mainstream" opinion against
>>the aforementioned "crank" hypothesis set forth by Ornish et al?
>
> In fact, the role of protein intake in the development of osteoporosis
> is almost totally ignored by researchers in the field...

Does the phrase, "almost totally ignored", have any kind of
scientific or rational merit?  If a dozen researchers conduct a
half-dozen studies showing that excessive protein intake increases
calcium excretion, it wouldn't logically matter whether 1,000 or
10,000 or 100,000 other researchers were ignorant of their
hypothesis.  Be that as it may, can you point to any opinion polls
that would lead us to believe that your statements are truly
representative of the mainstream opinions?

> and the few studies
> which have been done under controlled conditions haven't borne this out
> over time.

Name the studies, Steve.

> Most of the evidence for such an association comes from
> studies of populations which aren't necessarily controlled for genetic
> factors.  I think the evidence as such is comparatively weak.  It would be a
> "crank" argument to recommend that all people prone to osteoporosis should
> avoid dairy products.  This is premature.

You're certainly entitled to your opinion, but needless to say, you
haven't done any research in this area.  Nor have you presented any
evidence to indicate that you're familiar with the general literature
in the field.

>>>>Ok, so you've had a 20 year interest in pharmacology, but I take
>>>>it that you don't actually have any degree of any kind in
>>>>pharmacology?  Is that right?
>>> No degree.  Three courses at Harvard Medical School, which I took out
>>> of my own interest.  So what?
>>
>>Thanks for your honesty.  I'm beginning to understand why you
>>typically make a point of labeling your critics pejoratively
>>as "ankle biters" while portraying your own position as "mainstream".
>
> What a stupid comment.

Whether my comments are stupid or not won't change the fact that
your own "credentials" are close to non-existent, and hence, your
frequent appeals to authority are hypocritical.   To illustrate,
it doesn't make much sense for you to belittle Dean Ornish's critical
opinions about osteoporosis, presumably because he hasn't published
any papers in the field, while crying, "So what?", when Ted Altar
persuaded you to admit the limitations in your own background.  The
truth of the matter is that it doesn't require credentials for
Steve Dyer, or anybody else, to critically analyze a body of
papers.  You're entitled to disagree, but don't expect us to treat
your case as a special exception to the rules that you zealously
impose on others.

--
Russell Lawrence, WP Group, New Orleans [phone]
[e-mail]   uunet!wpg!russ