that Cohen, who styles himself as a fearless truth seeker who has
"stood toe to toe with the most powerful and influential industry
in America, the dairy industry, and fear[s] no man or group of men,"
could have avoided this scandal merely by standing toe to toe with
Stephen Walsh and answering his very legitimate questions. Those
questions were posed by Walsh, and later by Jeff Nelson and independently
by me and (again independently) by Stephen Kaufman in the very same
spirit as Cohen's own avowed mission "to level the informational
playing field for all consumers so that they may be empowered to
make informed decisions that bear on the health and welfare of themselves
and their children."
this letter not just to commend and defend Stephen Walsh but because
I'm concerned that some people, strongly predisposed to believe
Robert Cohen, will read one (in particular) of Walsh's succinct
criticisms and conclude it's just one man's word against another's.
I fear that Stephen underestimates many people's distrust of scientific
authority. That distrust is often very well founded; but not in
this case. For that reason -- and at the risk of boring some VegSource
readers to death -- I'd like to rebut in detail what I
would refer to as "Cohen's Law of Calcium Absorption," which Cohen
enunciates in an email
to his notmilk mailing list as follows:
to absorb one milligram of calcium, one needs an equal milligram
of magnesium. Therefore, in examining calcium values of food,
one must also consider the amounts of magnesium."
As far as I
can tell, "Cohen's Law" is recognized by no dietitian, nutritionist,
or other scientist, including at least several who are vegans themselves.
Yet Cohen uses it to justify his claim that the soymilk that can
be made with the "SoyToy" milkmaker which he sells (I believe exclusively)
provides more calcium than any other soymilk -- or cow's milk, for
that matter (which Cohen habitually refers to as "liquid meat,"
even though it contains only 3% protein by volume and virtually
no fat in its "skim" form).
As a writer
who has long specialized in health and nutrition, I have never seen
any evidence to support Cohen's Law. I could have asked Cohen to
provide any evidence he might have; but the last time I asked him
to support some other outrageous claims (those detailed in Walsh's
letter), he persistently evaded my questions, posed an unanswerable
riddle instead, and wound up threatening to sue me and one of the
publications I edit. To quote the bizarre aside to his wife and
secretary Lisa with which he concluded an email to me at the time
(the parentheses are his):
"(Lisa -- please
file this. It's clear that I am being set up, and this so-called
reporter and his journal may very well be hit with a libel and
slander suit similar to the brief we are preparing for the JN/ES
thing. As per the other EMAILS, this needs to be well documented
presumably stands for Jeff Nelson and EarthSave.)
So here I am,
challenging Cohen's Law on a very public, high traffic website -- not
to air dirty vegan laundry in public or to indulge in undignified
"infighting," but to demonstrate that some of us (I hope most) hold
truth and public responsibility higher than any insecurities we
may have about "is this bad for the vegans?"
I think it's
good for the vegans.
Let me start
by saying that all the research I'm aware of utterly fails to support
Cohen, who loves
to impute bias, incompetence, or deceit to any scientist whose work
conflicts with his own numerous pseudoscientific claims, would probably
reject much of that research, because at least two of the leading
investigators --nutritionist Connie Weaver and physician Robert
Heaney -- are enthusiastic dairy boosters. But unlike Cohen, Weaver
and Heaney have graciously rendered unto Caesar that which is Caesar's.
Based on real science (much of it their own), they have publicly
supported the "not milk" alternative.
Weaver has said
that "calcium fortified soy milk is a good source of calcium, which
should be offered as an alternative to milk in school lunch programs."
Heaney is quoted in an article on the
website of EarthSave (an organization founded by John Robbins) as
saying: "The sheer quantity of calcium in dairy products certainly
makes them attractive sources, but they have no monopoly on calcium.
There's no reason in the world why you couldn't get an adequate
intake from a vegetable source."
and others scientists' research on the "fractional absorption" of
calcium from various foods (i.e., the percentage we absorb) is trusted
enough by vegan authorities to have been used as source material
in a recent book by two of the world's leading and most respected
vegan dietitians, Brenda Davis, R.D., and Vesanto Melina, M.S.,
R.D. The book is a rigorous self-help masterpiece called Becoming
Vegan. Basing their figures on a literature
review by Weaver and Plawecki published in 1994 in the American
Journal of Clinical Nutrition (see here
for a more recent full-text version), Davis and Melina cite the
fractional absorption of calcium from half a cup of cow's milk as
48 milligrams; that is, the average person absorbs 32% of the milk's
150 mg (milligrams) of calcium. But according to Cohen's Law, that
figure should be 16 mg -- because that's all the magnesium
contradiction of Cohen's Law is not unique to milk. It
appears to apply across the board.
among the foods studied by Weaver and associates and listed in Becoming
Vegan (Table 6.6, page 97) is "fruit punch with calcium citrate
malate." The research says we absorb 117 mg of calcium from a six
ounce glass. But the USDA's nutrient database says six ounces of
fruit punch contains only 4 to 7.5 mg of magnesium. (Most fruits
are a poor source of magnesium.) In other words, we absorb roughly
twenty times as much calcium from calcium-fortified fruit punch
as we're "supposed to" according to Cohen's Law.
indicates that the fractional calcium absorption from apple juice
and orange juice fortified with 250 mg of calcium citrate malate
is 42 and 36 percent, or 105 and 90 mg, respectively. Yet there
are just 12 milligrams of magnesium in a cup of frozen apple juice
and 25 in a cup of OJ -- another blatant violation of Cohen's Law.
It's not just
foods artificially fortified with calcium that violate Cohen's Law.
Closer to home, so do beans.
As with soybeans,
all beans typically contain similar amounts of magnesium and calcium.
Yet according to research by Connie Weaver and her associates we
only absorb about 20 to 25% of that calcium (see "Absorbability
of calcium from common beans," Weaver et al., Journal of Food
Science, 1993, 58:1401-1403 96 -- sorry, no link available).
Take white beans. (Please!) Despite their ample endowment of
159 mg of magnesium and 226 mg of calcium per 220 gram cup (cooked),
research says we absorb just 49 mg of that calcium. That's less
than a third of what Cohen's Law predicts.
In 1994, the
Journal of the American College of Nutrition published a
that, in effect, was a direct test of Cohen's Law. Titled "Effect
of magnesium on the intestinal absorption of calcium in man," it
found no effect whatsoever, regardless of whether the subjects had
a normal (about 250 mg/day) or a high (about 800 mg/day) magnesium
intake while on a normal (about 800 mg/day) or a very low (about
250 mg/day) calcium diet. I should add, however, that the study
boosted dietary magnesium levels with magnesium oxide, the inorganic
form you can find in the supplement section of any health food store.
The magnesium naturally present in foods is mostly organic
magnesium salts and chelates. But while the study is open to criticism
on those grounds, its results are entirely consistent with
the fractional absorption data for calcium that I've discussed above
-- and as we've seen, that body of data is, without any reservations,
entirely incompatible with Cohen's Law.
So what about
(dare I say it) conveniently justifies his allegation that
-- unlike other soymilks -- fully 100% of the small amount of calcium
in the soymilk from the milkmaker he aggressively promotes above all others
must be absorbed, because the milk contains as much magnesium
as calcium. (Cohen:
"In order to absorb one milligram of calcium, one needs an equal
milligram of magnesium. . . Homemade soymilk contains 32 mg of
both calcium and magnesium. Exactly the perfect proportion!") That's
an extraordinary claim, not only because there is no basis for the
Law it depends upon, but because the highest fractional absorption
rate reported by Weaver et
al. (and Davis and Melina in Becoming Vegan) is 61% (for
half a cup of broccoli).
In fact, according
to Davis and Melina, "the absorbability of calcium from soy beverages
(often fortified with tricalcium phosphate) is . . . about 24%."
(Becoming Vegan, p. 98.)
(and if I'm wrong to call it that, I invite Cohen -- to whom I will
email a link to this letter -- or anyone else for that matter, to
publicly correct me here on this forum) is almost trivial in comparison
to Cohen's attempted
character assassination of Stephen Walsh for daring to question,
among other things, Cohen's entirely unsubstantiated accusation
that a Norwegian research group perpetrated "the fraudulent study
of the century" when they dared to publish data suggesting that
milk may prevent breast cancer. (Stephen Kaufman and I will soon
be publishing our own independent report that corroborates Walsh's
charges, as well as Cohen's evasiveness and hostility when challenged
to support his claims.)
I've never met
Stephen Walsh, but I've exchanged many substantive emails with him,
privately and on "IVU-SCI," the science mailing list of the International
Vegetarian Union. A few months ago, when I was researching a complex article
on the controversy over milk, Stephen -- true to form -- suggested
that I was overestimating the evidence against milk in some instances.
At other times, he suggested I was underestimating it.
I consider Stephen
to be a consummate scholar and a role model for all "evidence-based
activists" (to coin a term). By adhering to "the data" and sound
reasoning -- and by resisting the cheap allure of hype, spin, selective
citation of evidence, and other forms of manipulation -- he has
proven to be as effective a
to dairy industry disinformation as he is to false anti-dairy
author of Dealing with Depression Naturally and editor of
The Aquarian, Winnipeg
Vegetarian, and plant-based. He hasn't had a drop of milk (that
he knows of) for two years -- not because he thinks milk is
a "deadly poison," as Robert Cohen describes it, but because the
dairy industry is deadly to cows.