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From: B. Harris)
Subject: Re: IGF-1 causes breast cancer!
Date: 19 May 1998 07:47:39 GMT

In <>
(amy) writes:

>It is not clear from these studies whether IGF-1 causes these cancers, or
>whether elevated IGF-1 accompanies some other factor that causes these
>cancers.  At the very least, researchers are hoping that measurements
>of IGF-1 will identify individuals at high risk of getting these
>cancers, so that surveillance might be increased.[2]  (However, it
>would be common practice in the U.S. for people under such
>surveillance to find their health insurance canceled, which tends to
>discourage participation in surveillance programs.)

   Nonsense.  As well argue that because we know that men with higher
PSAs tend to have higher risk of having prostate cancer, that men
getting such surveillance tend to get their health insurance cancelled.
Wrong.  Insurance companies usually pay without complaint for cancer
surveillance, even when it identifieds high-risk individuals (which it
can hardly help doing, obviously).  The reason is that it's cheaper to
catch cancer early than late.

>IGF-1 is a powerful naturally-occurring growth hormone found in the
>blood of humans. Dairy cows injected with genetically-engineered
>bovine growth hormone (rBGH) give milk containing elevated levels of
>IGF-1, and the IGF-1 in milk can pass into the blood stream of milk
>consumers. Cows' IGF-1 is chemically identical to that in humans.
>Ingested IGF-1 would ordinarily be broken down in the stomach, but the
>presence of casein in milk prevents such breakdown.[4,5,6,7,8] (See
>REHW #454.) Thus these latest cancer findings raise important public
>health questions about the safety of milk from cows treated with
>bovine growth hormone (rBGH).

    Not until a couple of other facts are in evidence.  IGF-1 is a
protein.  It's not enough to show that it's not broken down in the gut.
You also have to show that it's absorbed, and that the absorption from
an amount of milk normally consumed is enough to significantly raise a
person's IGF levels.  These are all quantitative questions.

   Example: suppose cows getting rBGH make milk with 33% more IGF-1.
That would hardly be anything to worry about, would it?  It would mean
that drinking 3 glasses of the new stuff is like drinking 4 glasses of
the old stuff.  Big deal.  First, we'd like to know if there is any
relationship at all to breast cancer and regular cow milk consumption,
if regular cow milk (no growth hormone treatment) contains levels of
IGF-1 even in the ballpark of that treated with rBGH.  If it does, the
relationship should already be clear.

   The problem is, I can find no such relationship in the literature
(when studies are properly controlled, which means that people of the
same race and country must be compared against each other, with milk
consumption the only variable).  If IGF-1 causes breast cancer in
humans, we should see such associations already from untreated milk.
Where are they?

>The latest study of IGF-1 and cancer, reported this week in the LANCET
>--approximately the British equivalent of the JOURNAL OF THE AMERICAN
>MEDICAL ASSOCIATION --examined 397 women with breast cancer, and 620
>carefully-matched controls.  Their blood had been drawn before any of
>the women were diagnosed with breast cancer, so this was a prospective
>study --the most convincing kind there is.  (The prostate cancer study
>reported in January was also a prospective study.[3])

   It's a quite convincing study that premenopausal women who make more
IGF-1 are at greater risk for breast cancer.  It's not terribly
convincing that orally ingested IGF-1, or even milk, causes breast
cancer in any animal, or in humans.  For that, you'd need an
epidemiologic study showing what you're interested in (in humans).  Or
an animal study where IGF-1 is deliberately administered in milk.  I
can find no such studies.  These are the bare minimum to even begin to
start scaring people over this issue.

   Come ON.  Women produce their own IGF-1.  Suppose (to use another
example of a protein hormone) you found that women with (say) high
insulin levels got more breast cancer, and that there was some insulin
in sweetbreads that didn't get digested.   Wouldn't you, at the very
minimum, want to see if women who ate more sweatbreads (animal
pancreases) got more breast cancer?   Sure.  Raising a ruckus until you
have this important datum is irresponsible.  No wonder it got the two
journalists fired.  There are lots of studies of nutrition in breast
cancer to see if there are any food associations between breast cancer
and particular foods.  Cows milk does not show up in these.  In fact,
in some of the largest and best controlled studies of diet and breast
cancer-- those in Seventh-day Adventists who eat varying amounts of
animal products, there is NO relationship between breast cancer risk
and animal product consumption.  But animal products are where all the
IGF-1 is.  Wups.  Only if Monsanto's product raised dietary IGF-1
levels to many times those otherwise to be found in a normal diet,
would such epidemiologic studies as we now have, be worthless.  But
such is not the case.

>It will be difficult for the U.S. Food and Drug Administration (FDA)
>to acknowledge that milk from rBGH-treated cows might be implicated in
>common cancers.

   Nonsense.  Once even the most basic epidemiologic studies are in,
they'll have no choice.  But they aren't.  IGF-1 occurs in the natural
diet.  Is its ingestion associated with cancer risk?  No.

                                          Steve Harris, M.D.

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   Why would people want to donate money to you for misinformation and
biololgically uninformed opinion?

From: B. Harris)
Subject: Re: IGF-1 causes breast cancer!
Date: 23 May 1998 10:57:57 GMT

In <> Mark Gold
<> writes:

>Well, we know that IGF-1 is protected when ingested as part of milk
>from the references in the Rachel's article mention in the last post.

   Comment:  Not IGF-1 in infant formula.  It's denatured.   As for the
IFG-1 in plain milk, the levels are not much higher than in standard
milk, and for rBGH milk are still within the normal concentrations
found in human breast milk (real scary stuff--eh?).  A 40% increase
(abstract appended) is a typical increase for rBGH treated cow's milk.
These levels are considerably less than the levels shown to have a
metabolic effect in calves in the study you quote (these were the very
high levels of IGF-1 typical of collostrum, NOT rBGH treated milk).  I
don't really know where you're getting the 1000% numbers, but it's not
from any study of pooled milk.  Basically, it's bunkum scare numbers
not representative of anything that will ever be on a shelf.  Let's see
you defend it as such.

   As for IFG-1 and breast cancer, we already have large studies
looking at Seventh-day adventists, showing NO correlation between
animal product intake and breast cancer risk in a population of varying
greatly in their animal product intake, but not otherwise culturally.
If natural levels of IGF-1 made a difference here, we'd see it.  We
don't.  Nor do I see a correlation between milk consumption and breast
cancer incidence anywhere else.  If the correlation doesn't show up
between NO milk and 4 glasses a day, why should it show up between 2
glasses a day and 2 glasses a day with 50% more IGF-1?

                                       Steve Harris, M.D.

Science 1990 Aug 24;249(4971):875-884
Bovine growth hormone: human food safety evaluation.

Juskevich JC, Guyer CG

Food and Drug Administration, Center for Veterinary Medicine, Office of
New Animal Drug Evaluation, Rockville, MD 20857.

Scientists in the Food and Drug Administration (FDA), after reviewing
the scientific literature and evaluating studies conducted by
pharmaceutical companies, have concluded that the use of recombinant
bovine growth hormone (rbGH) in dairy cattle presents no increased
health risk to consumers. Bovine GH is not biologically active in
humans, and oral toxicity studies have demonstrated that rbGH is not
orally active in rats, a species responsive to parenterally
administered bGH. Recombinant bGH treatment produces an increase
in the concentration of insulin-like growth factor-I (IGF-I) in cow's
milk. However, oral toxicity studies have shown that bovine IGF-I lacks
oral activity in rats. Additionally, the concentration of IGF-I in milk
of rbGH-treated cows is within the normal physiological range found in
human breast milk, and IGF-I is denatured under conditions used to
process cow's milk for infant formula. On the basis of estimates of the
amount of protein absorbed intact in humans and the concentration of
IGF-I in cow's milk during rbGH treatment, biologically significant
levels of intact IGF-I would not be absorbed.

Publication Types:
  Review, tutorial

  Comment in: Science 1990 Aug 24;249(4971):852-3
  Comment in: Science 1991 Jan 18;251(4991):256-7

PMID: 2203142, UI: 90364404


Domest Anim Endocrinol 1994 Apr;11(2):209-216
Somatotropin and insulin-like growth factor-I concentrations in plasma
and milk after daily or sustained-release exogenous somatotropin

Zhao X, McBride BW, Trouten-Radford LM, Golfman L, Burton JH

Department of Animal and Poultry Science, University of Guelph, Canada.

Effects of daily injectable or sustained-release bovine somatotropin
(bST) administrations on plasma and milk bST and insulin-like growth
factor-I (IGF-I) concentrations were monitored in 74 lactating cows
through early, mid- and late lactation. Treatments beginning at wk 4 of
lactation were excipient (CO, 24 cows) at 2 wk intervals, daily
injections of 10.3 mg bST (DI, 25 cows) and 350 mg sustained-release
bST at 2 wk intervals (SR, 25 cows). The duration of treatments was 40
wk. Data were first analyzed for the overall mean concentrations
covering the 40 wk treatment period. Overall mean plasma bST,
milk bST and plasma IGF-I concentrations were significantly increased
by both bST treatments (p < 0.05). On the other hand, milk IGF-I
concentrations were significantly increased (p < 0.05) only in the DI
group. Next, data were analyzed according to stage of lactation. The
bST treatments resulted in significant increases (p < 0.05) in plasma
and milk bST concentrations for all early, mid- and late lactation
periods. Even though plasma IGF-I concentrations were higher (p < 0.05)
in all lactation periods for bST treatment groups, higher milk IGF-I
concentrations (p < 0.05) occurred only in mid- and late
lactation periods for the DI group. The patterns of bST and IGF-I
concentrations in milk follows those of the plasma after bST

PMID: 8045102, UI: 94320416

Comment:   P values of .05, not .01, are barely enough to see
statistically.  They don't correspond to 1000% increases, but to
increases so small there is still a 5% chance there was no increase.
For comparison, the 40% increase in IGF-1 due to rBGH seen in the
paper below represents a p value of .01.

J Endocrinol 1991 Mar;128(3):457-463
The galactopoietic effect of bovine growth hormone in goats is
associated with increased concentrations of insulin-like growth
factor-I in milk and mammary tissue.

Prosser CG, Royle C, Fleet IR, Mepham TB

AFRC Institute of Animal Physiology and Genetics Research, Babraham,

Lactating goats exhibiting widely divergent responses to short-term (4
days) treatment with bovine GH (bGH) were retrospectively divided into
two groups based on the magnitude of this response. There was no
difference between groups in terms of the pretreatment milk yield, but
by day 4 of treatment milk secretion had increased by 4.99 +/- 2.5
(S.E.M.) ml/h (P greater than 0.05 compared with pretreatment) for
group 1 and 22.9 +/- 2.4 ml/h (P less than 0.001) for group 2. Plasma
GH increased in both groups, but concentrations were significantly
higher both before and during treatment in group 1 compared with
group 2. Plasma concentrations of insulin-like growth factor-I (IGF-I)
increased significantly during bGH treatment for both groups and there
was no significant difference between the two until day 4 of treatment
when levels of IGF-I in group 1 began to decline, whereas those from
group 2 were maintained. Concentrations of IGF-I in milk from goats in
group 1 were not significantly altered by GH administration, whereas
those in goats in group 2 were increased by 40% (P less than 0.01
compared with pretreatment). Levels of IGF-I in mammary secretory
tissue from four animals from group 1 were not altered by bGH
(2.8 +/- 0.2 and 2.77 +/- 0.08 nmol/kg tissue before and after
treatment respectively), but were significantly (P less than 0.05)
increased in four animals from group 2 (2.80 +/- 0.2 and 9.9 +/- 1.1
nmol/kg tissue).

PMID: 2013749, UI: 91193648


From: Steven B. Harris <>
Subject: Re: IGF-1 causes breast cancer!
Date: Mon, 25 May 1998 01:42:59 GMT

In article <>,
	Mark Gold <> wrote:

>>>The amount of IGF-1 in human breast milk is not relevant.  The
>concern about IGF-1 (at east one of the concerns) is that it has
>been shown to speed the growth of *already existing* cancer
>considerably.  Infants do not generally have cancer, but they do
>have a need for increased growth and the health protection that
>breast milk offers.  As you probably know, adults develop cancer
>that can take a decade or even decades to be detected (and many
>may die of other causes before the cancer kills them).
>With IGF-1, we would be speeding the cancer growth

    Comment:  What is this "we could" stuff?  Where is your
EVIDENCE?  There are thousands of potential carcinogens out there
which could be doing this, and could be doing that.  It takes
more than chicken little to pay attention to any one of them.
The Masai tribe, which subsists on milk, should be dying like
flies of breast cancer.  So show me.

   >> I would hope that people would not fall for these types of

    Burden of proof is on you.  The amounts of extra hormone are
well within the normal range of human dietary intake in milk
drinking populations, by all the evidence that exists in print.
If we cannot see milk's effects on cancer in normal epidemiology,
expecting to see this hormone's effect is irrational.

I repeat:
>>A 40% increase
(abstract appended) is a typical increase for rBGH treated cow's
milk. These levels are considerably less than the levels shown to
have a  metabolic effect in calves in the study you quote (these
were the very  high levels of IGF-1 typical of colostrum, NOT
rBGH treated milk).  I  don't really know where you're getting
the 1000% numbers, but it's not from any study of pooled milk.<<

>As I mentioned before, anyone can selectively pick their numbers
>and post abstracts.  In one paper you quoted, there was a 70%
>IGF-1 increase using Monsanto's version of rBGH over 10 cycles
>(see Table 7 in the Juskevich & Guyer review).

Comment: A reasonable increase.  And not a scary one, since it's
well within the normal range of IFG-1 in milk, and certainly
within the normal range of milk intake for adults.

>>>  I posted a reference in The Lancet where Eli Lilly said
>that IGF-1 could increase by as much as 1000% using their version
>of rBGH.<<

Comment:   "Could"?  I'm afraid this qualifies as not well
qualified scaremongering.   Get back with us when this is seen on
your grocery shelf.

>    >>Like Monsanto, Eli Lilly doesn't publish their pre-approval
>studies. There are other studies that show a greater than 70%

    Quote them.

>  >>  And I am aware of studies which show less of an increase.

    I've no doubt of that, since this includes most of them.  But
cite your cites and we'll look at all the evidence available in
print, on medline.  You don't just get to bow out by pretending
you can find evidence in the literature of just any IGF-1
increase you want to find.  You can't. The evidence isn't there.
It hasn't been seen in real cows and real milk for production.
Pretending it has, is silly.  You can puff all you like, and you
won't produce it.  And I'll be right here to remind people that
you can't.

   >>Did you read the information I posted about Seventh-day
>adventists being largely *lacto*-ovo-vegetarian???  This means
>that they eat dairy and some may eat lots of it.  This renders
>any of these studies irrelevant to the subject of IGF-1 and
>breast cancer.<<

    Nonsense.  What, do you think that every SDA drinks a quart
of milk, and no more and no less, as part of their religion?  The
fact that they drink milk and some drink a LOT (to make
up for the meat that half of them don't eat), Seventh-day
Adventists make an first class choice of a population with lower
than normal breast cancer risk (which they have) and higher than
normal average milk intake.  But with quite enough variation to
see a milk dose effect, if there was one.  Which there is not.

    If you don't like SDAs, it's not as though there are not
plenty of epidemiologic studies of breast cancer and diet.  Those
that show a milk correlation within populations, show mixed
results.  Milk can be protective against breast cancer in
epidemiologic studies (see the first ones below)-- a neat trick
if it contains killer hormones.  To get a positive correlation
you have to do the dishonest trick of comparing populations who
have genetic differences as well as dietary differences.  A Dr.
N. Barnard "Physicians For Animal Rights" trick.

   >>You have yet to show one study where non-dairy users were
>compared to dairy users for breast cancer rates (controlling for
>other factors, of course).<<

    As such a study would be by definition impossible (since a
population which drinks NO milk will certainly have other factors
operating, like lactase deficiency and different religion or
race), what you ask for would be a rather unlikely, perhaps
impossible study.  This kind of vegan co-variable thing also
makes international comparisons of diet (particularly milk)
worthless (osteoporosis looks like it's caused by milk when you
do the epidemiology between countries, but within-country studies
show it's the other way around).  But one can look at a range of
milk intake in the same population, and get some epidemiologic
answers.  I've included some of these.  They are partly con-
founded by the problem that saturated fat in milk is a suspected
breast cancer risk.  Even so, most of the studies (not all) go
the other way.  If IGF-1 caused cancer at these levels or near,
this could not be.  The effect would show clearly
epidemiologically, like smoking.

>   >>In addition, simply increasing the level of an
>extremely powerful hormone (one that increases cancer growth at
>nanogram levels) by 70% and hoping that it will not effect cancer
>is not a responsible position on the part of Monsanto, IMO.<<

    If it's within the variation seen in the population already,
why isn't it?  It's quite possible the glass of "organic" milk
you had today has 70% more IGF-1, just by natural variation among
cows and dairies.  This hormone is powerful when injected, and
does all kinds of things.  But it has yet to cause cancer at any
oral intake in any animal, and that's the bottom line.  We have
no evidence it's even an oral carcinogen at ANY dose.  All we
have is handwaving and some evidence that really high oral doses
get enough hormone into calves to have hormonal effects.  That
isn't enough.  The IGF-1 variations Monsanto plans are seen in
normal variations in people living around the world,
and by the best epidemiology we can do, do no harm.  So what
you're feeding us is utter nonsense.  Mother's milk, indeed.
Next you'll be starting on apple pie.

>   >>Here's another interesting question.  The FDA has finally
>admitted that rBGH that Monsanto uses and natural BGH are

   Yes, I think by one amino acid in 190 or something.  So what?

  >>Where is the evidence that it is fully destroyed by
>pasteurization -- and since it is not fully destroyed, where are
>the long-term studies of rBGH in milk which would give us some
>confidence that there are no long-range and potentially
>serious problems.<<

    Unlike IGF-1, Growth Hormone from animals is not hormonally
active in humans.  If it was, they wouldn't have had to use
cadaver pituitaries to extract it for humans, which tissue
extract gave some kids CJD (like mad cow disease) in 1985 before
human GH was finally genetically engineered.  The idea
that cow GH is going to do anything to people, at doses not much
different than are in milk already, is ludicrous.  They are using
rBGH in cows, not human growth hormone.  If it was active in
feed, even as the right stuff, they'd be FEEDING it to the cows.

                                 Steve Harris, M.D.

>Cancer Lett 1997 Mar 19;114(1-2):251-253
>Diet and breast cancer risk in a cohort of Finnish women.
>Jarvinen R, Knekt P, Seppanen R, Teppo L
>Department of Clinical Nutrition, University of Kuopio, Finland.
>The associations between dietary antioxidant vitamins, dietary
>fiber, and selected foods and risk of breast cancer were studied
>in 4697 initially cancer-free women, aged 15 years or older. At
>baseline (1967-1972) the women were interviewed for total
>habitual diet over the preceding year. During a
>25-year follow-up period 88 breast cancer cases were diagnosed.
>There was a significant inverse gradient between milk consumption
>and occurrence of breast cancer, whereas higher consumption of
>fried meat was associated with increased risk of breast cancer.
>No significant relationships were found between the
>intakes of vitamin E, vitamin C, beta-carotene, lycopene, lutein
>or dietary fiber and the occurrence of breast cancer.
>PMID: 9103304, UI: 97256463
>Br J Cancer 1996 Mar;73(5):687-691
>Intake of dairy products and the risk of breast cancer.
>Knekt P, Jarvinen R, Seppanen R, Pukkala E, Aromaa A
>National Public Health Insitute, Helsinki, Finland.
>The relationship between intake of dairy products and risk of
>breast cancer was studied in 4697 initially cancer-free women,
>aged 15 years or over. During a 25 year follow-up period after
>the collection of food consumption data, 88 breast
>cancers were diagnosed. Intakes of foods were calculated from
>dietary history interviews covering the habitual diet of examin-
>ees over the preceding year. There was a significant inverse
>gradient between milk intake and incidence of breast cancer, the
>age-adjusted relative risk of breast cancer being 0.42 (95%
>confidence interval=0.24-0.74) between the highest and lowest
>tertiles of milk consumption. The associations with respect to
>other dairy products were not significant. Adjustment for potent-
>ial confounding factors, i.e. smoking, body mass index, number of
>childbirths, occupation and geographic area, resulted in
>only a minor change in the milk intake-breast cancer relation.
>Nor did adjustment for intake of other foodstuffs and nutrients,
>e.g. energy, carbohydrates, protein, fat, vitamins and trace
>elements, alter the results. No significant interactions between
>milk intake and demographic or dietary variables or time of
>cancer diagnosis were observed. Our data suggest that
>there is a protective effect, dietary or habitual, associated
>with consumption of milk that overwhelms the associations between
>different other factors and risk of breast cancer.
>PMID: 8605108, UI: 96184045
>Int J Cancer 1995 Sep 27;63(1):13-17
>Dietary fat and the risk of breast cancer: a prospective study of
>25,892 Norwegian women.
>Gaard M, Tretli S, Loken EB
>Cancer Registry of Norway, Institute for Epidemiological Resear-
>ch, Montebello,
>In this prospective study, the relationship between energy and
>fat consumption and the risk of breast cancer was examined.
>Between 1977 and 1983, 31,209 Norwegian women, 20 to 54 years of
>age attended a health screening. The attendees were given a
>food-frequency questionnaire to be completed at home,
>and this was returned by 25,892 (83%). During the 7 to 13 years
>of follow-up, 248 cases of breast cancer were identified for
>analysis by linkage to the Norwegian Cancer Registry. The
>relative risk of women who ate meat more than 5
>times a week, as compared with those who consumed meat twice or
>less than twice a week, was 2.44. Consumers of 0.75 litres or
>more of full-fat milk daily had a relative risk of 2.91 compared
>with those who consumed 0.15 litres or less. A
>positive relationship was found between those reporting the
>highest quartile of mono-unsaturated fat consumption and the risk
>of breast cancer. The main foods contributing to the mono-unsa-
>turated fat index were edible fats, meat and milk.
>PMID: 7558440, UI: 96000238
>Am J Epidemiol 1988 Jan;127(1):42-49
>Diet and cancer mortality in the counties of Sweden.
>Rosen M, Nystrom L, Wall S
>Swedish Planning and Rationalization Institute for Health and
>Social Services,
>Stockholm, Sweden.
>The association between standardized cancer mortality rate ratios
>from 1969-1978 and dietary practices was examined in an ecologic
>study of the 24 counties of Sweden by means of several
>independent data sources. The study supports the hypothesis that
>a high intake of cereal fiber protects against
>colorectal cancer (r = -0.75 for males and r = -0.67 for female-
>s). This study found no association between fat intake and
>colorectal cancer. However, a negative correlation between milk
>consumption and this type of cancer was found. A suggested
>hypothesis is that calcium protects against colorectal
>cancer, since milk is the major source for calcium intake in
>Sweden. This could indicate that, for societies with a high fat
>intake, preventive measures which increase the intake of fiber
>and milk or calcium might have a greater impact on
>mortality from cancer of the colon and rectum than would a
>moderate decrease in the intake of fat. There are no indications
>in this study that fat intake promotes breast cancer.
>Publication Types:
>  Review
>  Review literature
>PMID: 2827460, UI: 88103495
>J Natl Cancer Inst 1986 Sep;77(3):633-636
>Consumption of dairy produce and alcohol in a case-control study
>of breast cancer.
>Le MG, Moulton LH, Hill C, Kramar A
>In a French case-control study of 1,010 breast cancer cases and
>1,950 controls with nonmalignant diseases, the risk of breast
>cancer was found to be positively associated with frequency of
>cheese consumption and the level of fat in the milk consumed. A
>negative association was found between frequency of
>yogurt consumption and the risk of breast cancer. No association
>was found between the consumption of butter and the risk of
>breast cancer. The positive association between a daily
>consumption of alcohol and the risk of breast cancer previously
>reported was not altered when dairy produce consumption was
>taken into account.
>PMID: 3091896, UI: 86308830

From: B. Harris)
Subject: Re: IGF-1 causes breast cancer!
Date: 26 May 1998 11:02:51 GMT

Mark Gold <>
Message-ID: <Pine.BSF.3.96.980525013822.16818A-100000@shell2.>

  >>As I said, it is not up to potential victims to prove that
>adulterated milk is safe.  IGF-1 levels has been linked to both
>prostate and breast cancers.<<

Comment:   Not ingested IGF-1.  These are blood levels.  Which
have not been shown to change significantly with oral IGF-1
ingestion of the sort you get in milk.

GOLD  >>  IGF-1 has been shown to increase in rBGH milk

Comment: Not by much.

GOLD >> and it survives digestion.<<

Comment: A tiny fraction does.

>>  In my opinion, it is irresponsible to approve this for human
consumption without extensive testing.<<

  In your opinion.   Amounts vary in normal milk by more than a
factor of six,  rBGH increases the average by less than a factor
of one, and you're terrified.  It's normally present on average
in cow milk in amounts comparable to that in your own saliva
(which you drink several *quarts* a day of), and you just get the
heebie jeebies about the 70% extra that might show up in a few
*glasses* of milk.  Gee, Mark, time for your Xanax.

   >>Apparently, you have never heard of a threshold level!  By
this logic, if 2-4 cigarettes per day increase lung cancer rates
a non-statistically significant increase of 1%, than it's okay to
increase the average use to 4 cigarettes per day!  I don't think
that any scientist would assume that an increase in the level of
a powerful hormone is "safe" for everyone simply because someone
else in the world is exposed to that level.  That's
irresponsible, in my opinion.<<

   Look, I don't know how to break this to you, but the kind of
analysis you call "irresponsible," is the standard method of
determining safe limits for toxins and polutants in home and
workplace.  If the amounts extra added by some factory or change
are less than the normal variations, thought to be harmless, and
are a lot less than you get naturally (your saliva, remember?),
then it's assumed that it's nothing to worry about.  You're about
50 years too late on this policy, and you shouldn't start with
milk.  Try lead.  Carbon monoxide.  Radon.  Hundreds of natural
chemicals in plants, all known to be carcinogens.

  >>Not quite.  A 70% increase is still a 70% increase no matter
how you twist it.  There is no "normal range in milk" as far as
the consumer is concerned.  Milk is mixed in tanks from cows at
various levels of IGF-1 depending upon the period in the cycle,
etc.  But there is an average in the tank when the milk is mixed

   And that average depends on the tank, as you see below, and
it's still very wide even in the tank.  In this paper, in fact,
it was found that bulk milk tank samples varied in IGF-1 by as
much as in the individual cows-- by 640 %.  Which would mean that
a 70 % increase over the average found in all tanks together
would still not put the level as high as found in bulk tanks with
the highest levels seen in the 100 tanks tested in this study.
Do you really think they mix ALL the milk in the country
together, from all the cows in every season, and blend, before
they let you, Mark Gold, drink any?  How do you know which bulk
tank at your dairy you're getting it from?  Since the variations
are very large, it would appear that you should be concerned
about these factors, and buy milk only at certain times in the
year, and certain tanks, and from certain breeds (want to bet
that breeds that produce more milk, like Holsteins, make more
IGF-1?).  Or buy milk only from certain dairies.  Or spit more,
so you don't swallow that saliva, which is worse in terms of
IGF-1 load, and surely causes cancer if milk does.

>>Now your pretending to know exactly what Seventh-Day Adventists
eat.  Some are vegan (not many), some may eat more dairy, some
may eat less dairy.  They also may have a greater vegetable and
fruit intake which may effect breast cancer rates.  You're
guessing at dairy intake and not controlling for other factors in
this mental epidemiological study.  Sorry, but you'll
have to do better than this. <<

   Gladly.  But I have this "mental" study and you don't.  So which
of us is guessing?  You get your copy, and then we'll discuss it.
Meanwhile you're just blathering and embarrassing yourself.

   Milk studies are indeed complex because of the fat effect and
the fermentation effect.  The point is that no clear answer
emerges from them.  If IGF-1 was bad for you at some point, it

GOLD  >> Pasteurization increases IGF-1 levels.<<

Comment:   It does not.  See abstract below.

  >> Also, organic dairy is often not homogenized. Homogenization
reduces the size of the fat molecules significantly.  There is
quite a difference between homogenized rBGH dairy with 70% more
IGF-1 and with much smaller fat molecules and organic,
unhomogenized dairy.<<

   When you show that homogenization increases IGF-1 absorption,
you'll have a relevent fact.  But no such studies exist.  In fact,
as noted, no study exists showing even increased blood levels of
IGF-1 from relatively slight increases in oral ingestion (of
the sort that happen if you drink milk AND saliva <g>).  It's
all a very unlikely theory.

  >> So, any comparison between rBGH dairy in the U.S.
and that of milk ingested by tribes is not relevant.  You have
yet to produce any safety studies on the artificial creation of
"rBGH'd", pasteurized and homogenized milk. <<

   I'll do it when you produce safety rules on breast feeding, or
swallowing your own spit.  Or drinking 3 glasses of milk rather
than 2.   Meanwhile, I'll just stay here and point out how silly
you're being, talking about the kinds of increases you're talking

[in reference to rBGH vs BGH]  >>   Yes, [they are different], I
think by one amino acid in 190 or something.  So what?

>>It's different, so it may have some health unknown health
effects.  Your hypothesis that it does not have effects is
interesting, but much of the rest of the population may want to
actually have to significant human studies conducted rather than
rely on your expertise.<<

  Ridiculous again.  There are unknown health effects to
everything you do.  Including spitting less, as pointed out.  We
don't need a lifetime or 10 year study of most of them.  In
biology, certain things have been found to be true, and one of
these is that only human growth hormone works on humans.  You may
have found the first exception with rGBH (you get the Nobel for
that if true), but it's pretty unlikely.  We have plenty of
better things to do with our research money than chase after
scenarios as unlikely as this.  Like I said, you do an experiment
every time you selectively breed an animal, like breeding a cow
to get more milk yield, which certainly partly involves breeds
with different hormone levels.  YOUR problem is that you worry
just when it's done the high tech way.  But like I say, you're
decades too late.

   I had a "blood orange" the other day, something I'd never had.
Interesting.  It probably had hundreds of chemicals in it I'd
never eaten before.  Did I demand they do a 10 year study in
chimps before I'd try it?  No.  Life's too short for anxiety
levels like those.  Pay attention to the risks you KNOW are out
there.  If you spent half the time on the net you do about food
changes, working on getting a bigger car to drive, you'd probably
be a lot safer.  Unless, of course, you spread food anxiety for a
living, with some kind of newsletter.  Which is what I'm
beginning to suspect.

                                Steve Harris, M.D.

J Dairy Sci 1991 Sep;74(9):2905-2911
Factors affecting insulin-like growth factor-I concentration in
bovine milk.

Collier RJ, Miller MA, Hildebrandt JR, Torkelson AR, White TC,
Madsen KS, Vicini JL, Eppard PJ, Lanza GM

Monsanto Company St. Louis, MO 63198.

To establish the naturally occurring range of insulin-like growth
factor-I concentrations in bovine milk, samples from individual
cows (n = 409) managed on five Missouri dairy herds were assayed.
Parity, stage of lactation, and farm affected milk insulin-like
growth factor-I concentration. Milk insulin-like growth factor-I
concentration was higher in early lactation than mid and late
lactation with concentrations in multiparous cows exceeding those
in primiparous cows. Insulin-like growth factor-I concentration
was negatively correlated to milk production the day of sample
collection (r = -.15) and not correlated to predicted 305-d milk
yields. Unprocessed bulk tank milk samples (n = 100) from a
commercial processing plant had a mean concentration of
insulin-like growth factor-I in milk of 4.32 ng/ml with a range
of 1.27 to 8.10 ng/ml. This distribution was similar to the range
detected in samples from individual cows, but values were lower
than those reported for human milk. Concentration of insulin-like
growth factor-I in milk was not altered by pasteurization (at 79
degrees C for 45 s). However, insulin-like growth factor-I was
undetectable in milk heated to temperatures (121 degrees C for 5
min) required for infant formula preparation or in commercially
available infant formula. These data indicated that insulin-like
growth factor-I is a normal but quantitatively variable component
of bovine milk that is not destroyed by pasteurization but is
undetectable in infant formula. Concentration of insulin-like
growth factor-I in bovine milk is lower than concentrations
reported for human milk yet similar to those reported for human

PMID: 1779049, UI: 92138820


From: B. Harris)
Subject: Re: Bovine Milk= Not Good Food (was :Re: Got milk? - NOT)
Date: 31 Mar 1999 10:58:48 GMT

In <> (alexs) writes:

>It's not the semi-digestible proteins in bovine milk,
>but the growth hormones.  Chronic exposure to these
>natural substances is hypothesized to be the problem.

   They can hypothesize all they like, but until they succeed in giving
some animal cancer by *feeding* it growth hormones (GH or IGF), they
are just going blue sky pipe dreaming.  Anyone can make a hypothesis.
You can hypothesize that moon is made of cheese.  Gettting evidence for
its truth is another matter.

From: B. Harris)
Subject: Re: Bovine Milk= Not Good Food (was :Re: Got milk? - NOT)
Date: 1 Apr 1999 07:37:59 GMT

In <> (alexs) writes:

>Drinking grown hormones every day?  No thanks.
>(BTW human and bovine IFG-Is are identical and, as
>demonstrated by the study cited, both will pass thru the
>intestinal wall).

    The problem is the your own arguments undermine your position.
Bovine IGF is identical to human IGF.  So it shouldn't have some
special harmful cow property.  It worst it will do nothing more to you
than your own IGF will.  And humans DO make IGF every day.  Right to
the end of their lives.  Does drinking milk provide enough IGF even to
show up as an increase in human IGF blood levels?  Absolulely unknown.
For that matter, there is a great deal of variation between humans as
to their own IGF levels.  Is there a shred of evidence that IGF levels
correlate with reduced life span?  No, on the contrary, lower IGF
levels correlate with chronic disease (though I suspect the cause and
effect runs the other direction).  Studies in humans that IGF levels
correlate positively with this or that disease miss the point.  They
correlate negatively with other diseases.  And generally positively
with life span and health.  And in not one of these cases do we know
whether the correlation is causal or simply spurious (due to a
confounder which influences both IGF and the disease or health of the
person), and in cases where the relationship IS causal (if any there
be) which direction it runs.

   In short, we know almost nothing about this subject.  What we do
know is a general principle: that protein hormones are not well
absorbed orally, and there is NO evidence that IGF is an exception
(there is evidence that it's absorbed, but not that it's absorbed
well).  We also know that IGF levels naturally vary greatly in humans,
with no obvious ill effects *overall* from having higher rather than
lower levels.

    Thus, your criticism of milk drinking is that it contains a naural
substance already in our bodies and not known to be toxic, which might
be absorbed in quantities large enough to influence levels already in
our bodies, though there is no evidence for it.  Gosh, what a scary

    At this point, it comes to me that somebody must have measured IGF
levels in adult Asian populations vs adult Nordic populations.  The IGF
levels ought to be a lot higher in Westerners if milk is capable of
influencing this.  Are they?  If IGF in milk causes cancer, there
should be a correlation between milk consumption and GI cancer (the
place which will naturally be exposed to more IGF).  Is there?   Do
Asians, who drink far less milk, get a lot less GI cancer?  Well, no.
Obviously a lot of confounding variables here.

                                            Steve Harris, M.D.

From: B. Harris)
Subject: Re: Bovine Milk= Not Good Food (was :Re: Got milk? - NOT)
Date: 1 Apr 1999 10:33:35 GMT

In <> (alexs) writes:
>On 31 Mar 1999 11:06:21 GMT, B. Harris) wrote:
>>   The real problem is proving that the amounts of IGF-1 you get in
>>milk are a cancer risk if taken orally.  Nobody is close to doing that.
>I'll just paste this from a later post in this thread.
>"... Mero A, Miikkulainen H, Riski J, Pakkanen R, Aalto J, Takala T
>     Effects of bovine colostrum supplementation on serum IGF-I,
>     IgG, hormone, and saliva IgA during training.
>     J Appl Physiol. 1997 Oct;83(4):1144-51.
>     PMID: 9338422; UI: 97479511.
>showed that bovine colostrum supplement increased serum insulin-like
>growth factor I (IGF-I) concentration in athletes, but I'm not sure if
>that such a good thing in long term.     "
>So it has been demonstrated that bovine IGF-1 does indeed have the
>capability of being absorbed in the gut & getting into the


   Okay, I'll meet you halfway.  I looked up data for colostrum.
Levels of IGF in bovine colostrum go from 248-1850 ng/mL at first
milking to 21-101 ng/mL at the fifth milking.  But levels in normal
diary cow milk are about 1.6-6.0 ng/mL.  They go up in normal milk from
25% to 400% with rGBH treatment, depending on the study.  The average
is less than a factor of 2.  So colostrum has at first 75-560 times as
much IGF as milk, dropping to 6-30 times.  Divide those numbers by 2
for rGBH milk.  I don't know how much IGF is in this Finnish colostrum
sports product, but the atheletes drink 1/2 to 1 cup of the stuff.
That corresponds to how much milk, now?  And it did what to their IGF
levels?  Inquiring minds want to know.  If I ever decide to drink 100
cups of milk a day (say), I want to know where my IGF levels will be.
Out of normal range?  Increased, but still well within normal range?

>And no, it's not speculation & certainly not BS. Wrong sex, and milk's
>a secretion, not excretion.  Call it a hypothesis, with a chain of
>evidence and causative factors providing ample justification therefor.

   Do let me remind you that milk consumption does not correlate with
breast cancer incidence. For that, you have to add cheese.  Only milk
FAT consumption correlates with breast cancer risk, and even there the
most recent evidence (which lately made the papers) is that it's the
calories, not the fat, that makes the difference.  Doesn't matter what
kind of fat a woman eats, it's the how fat SHE gets that matters.
Something I, as a long time studier of dietary restriction in animals
(you should see mice with breast cancer-- horrible) could have told
you.  Serum total IGF-1 levels don't change with obesity, but FREE
IGF-1 levels go up.  As you would expect, since the stuff is a lot like
insulin metabolically, and obese people are resistant to insulin action
also.  The body compensates.  If you ever find a correlation between
IGF-1 levels and breast cancer, you'll have to control for body mass
index to see if it's real.  And even then you won't know whether you're
seeing cause and effect, or just association due to a confounder which
hasn't been located.  Blood sugar goes up with obesity, and blood sugar
levels correlate very well with breast cancer risk in women.  Does
blood sugar cause breast cancer?  Blood cholesterol correlates with
breast cancer risk.  Does blood cholesterol cause breast cancer?  Being
Jewish and living in the city correlates with breast cancer risk.
Should all women therefore convert to Christianity and move to the
country? Think, man.

                                        Steve Harris, M.D.

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