Monsanto's rBGH: A Cancer Hazard?

rBGH Produced Milk:
Cancer From Your
Dairy Products?
Rachel's Environment & Health Weekly #598

"Because of FDA's and Monsanto's aggressive steps to prevent labeling of
rBGH-produced milk, U.S. consumers of milk, chocolate milk, buttermilk,
cream, whipped cream, ice cream, iced milk, cheese, cottage cheese, cream
cheese, yogurt, frozen yogurt, custards --and perhaps many baked goods as
well --are very likely ingesting increased quantities of IGF-1 today."

Breast Cancer, rGBH, and Milk

A study of U.S. women published May 9 in the LANCET links insulin-like
factor-1 (IGF-1) with breast cancer.[1,2] Earlier this year a study linked
IGF-1 to prostate cancer.[3] (See REHW #593.) Prostate and breast cancers
major killers of men and women in the U.S. and in other industrialized
countries. IGF-1 levels are now being artificially increased in much of the
cows' milk being sold throughout the U.S. These new cancer studies raise
serious questions about the wisdom of allowing IGF-1 levels to be raised in

The latest study[1] found a 7-fold increased risk of breast cancer among
pre-menopausal women younger than age 51 with the highest levels of IGF-1 in
their blood. The prostate cancer study published in SCIENCE in January,
found a 4-fold increase in risk of prostate cancer among men with the
levels of IGF-1 in their blood.[3] Thus IGF-1 in blood is associated with
larger relative risks for common cancers than any other factor yet

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
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

IGF-1 is a powerful naturally-occurring growth hormone found in the blood of
humans. Dairy cows injected with genetically-engineered bovine growth
(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).

rBGH is injected into cows to extend by several weeks their period of
lactation, and thus to force them to produce more milk. rBGH is not
needed in
any way because U.S. dairy cows already produce such an excess of milk that
the U.S. government spends more than $200 million each year purchasing
surplus milk, a subsidy to the milk industry. (See REHW #381, #384.) Because
rBGH injections can cause numerous ill effects in cows, veterinarians in
Germany have refused to administer rBGH to cows on grounds that it violates
their professional code of ethics, which forbids intentional harm to
(See REHW #483.) U.S. veterinarians have not taken a similar stand.

The latest study of IGF-1 and cancer, reported this week in the LANCET
--approximately the British equivalent of the JOURNAL OF THE AMERICAN
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])

The study found no relationship between IGF-1 in blood and breast cancers
among the entire group, or among the post-menopausal group. However among
pre-menopausal women increasing levels of IGF-1 in blood were strongly
associated with increasing risk of breast cancer in a consistent
dose-response relationship. Adjusting for other known breast cancer factors
(age at which menstruation began; age at birth of first child; number of
children; family history of breast cancer; and weight in relation to height)
did not change the results.

Two previous studies had reported a relationship between IGF-1 levels in
blood and breast cancer.[9,10] However those were "retrospective" studies in
which the IGF-1 levels in blood were measured AFTER the diagnosis of breast
cancer, so it was possible that the cancers caused the IGF-1 increases
instead of the IGF-1 increases causing the cancers. This latest study
minimizes the likelihood that IGF-1 levels are raised by breast cancers.

The authors of the latest study say there is "substantial indirect evidence
of a relation between IGF-1 and risk of breast cancer." They point to
experiments showing that IGF-1 enhances the growth of cancerous breast cells
in mice, and growth of healthy breast cells in rhesus monkeys. In humans,
very-low-calorie diets protect against breast cancer and they also reduce
blood levels of IGF-1. Low birth weight is protective against breast cancer
and low birth weight also leads to low levels of IGF-1. Tall women tend to
have an increased likelihood of breast cancer and they also tend to have
increased levels of IGF-1. Tamoxifen, a chemical now being used to prevent
breast cancer, is known to reduce IGF-1 levels in the blood. Several other
chemicals thought to protect against breast cancer --such as vitamins A
and D
--may also lower blood levels of IGF-1.[11]

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. Historically, FDA has maintained a very close relationship with
Monsanto, the chemical company that spent a billion dollars developing rBGH.
FDA approved rBGH for cows in 1993 and issued regulations that made it
to be illegal to label milk rBGH-produced or rBGH-free. Some of the FDA
officials who approved rBGH and who established the regulations discouraging
labeling had previously worked for Monsanto. (See REHW #381.) In 1994,
Monsanto sued two grocery stores that labeled milk rBGH-free, because the
chemical giant feared that, given a choice, consumers would reject
rBGH-produced milk. FDA's anti-labeling regulations --signed into law by a
former Monsanto official --were clearly intended to help Monsanto succeed in
this marketing ploy. Eleven separate surveys have shown that Americans
strongly prefer to have rBGH-treated milk labeled as such. (See REHW #381.)

Monsanto officials say their rBGH product has been so successful among dairy
farmers that they are building a new factory in Augusta, Georgia to
produce a
lot more of it. They say they intend to market the product world-wide.[12]
However in Canada and the European Union, rBGH has so far not been approved
for use, partly because of unanswered health questions. The new studies
linking IGF-1 to breast and prostate cancers are unlikely to help rBGH gain
approval in Canada or Europe.

Because of FDA's and Monsanto's aggressive steps to prevent labeling of
rBGH-produced milk, U.S. consumers of milk, chocolate milk, buttermilk,
cream, whipped cream, ice cream, iced milk, cheese, cottage cheese, cream
cheese, yogurt, frozen yogurt, custards --and perhaps many baked goods as
well --are very likely ingesting increased quantities of IGF-1 today. (See
REHW #383, #454, #483.)

The milk industry --a powerful lobby in the U.S. --is currently conducting a
campaign to increase milk consumption and top U.S. health officials are
participating in the campaign. Recent advertisements show Donna Shalala, the
U.S. secretary of health and human services, with a glass of milk in her
and a "milk mustache" on her upper lip.[13] Ms. Shalala oversees the U.S.
FDA, among other agencies.

A few bold companies --such as Ben and Jerry's, makers of gourmet ice cream
--now label their products as rBGH-free. However, other companies, such as
Whole Foods, Inc. --an "organic" grocery chain that owns Fresh Fields stores
--claim to sell no dairy products containing rBGH. Yet the Annapolis,
Maryland Whole Foods outlet sells cheeses from Cabot Dairies in Vermont and
Cabot readily acknowledges that it uses some milk from rBGH-treated cows.
Thus rBGH may be even more widespread than advertisements and store policy
statements would lead consumers to believe. In the U.S., it is legal for
merchants to mislead consumers in this way.

Dr. Samuel S. Epstein at the University of Illinois in Chicago in 1996
published a paper arguing that IGF-1 from rBGH-treated cows may well promote
cancer of the breast and of the colon in humans who drink such milk. Epstein
pulled no punches: "In short," he wrote, "with the active complicity of the
FDA, the entire nation is currently being subjected to an experiment
involving large-scale adulteration of an age-old dietary staple by a poorly
characterized and unlabeled biotechnology product [rBGH, which is
engineered by Monsanto]. Disturbingly, this experiment benefits only a very
small segment of the agrichemical industry while providing no matching
benefits to consumers. Even more disturbingly, it poses major potential
public health risks for the entire U.S. population," Dr. Epstein wrote.[14]

Monsanto has bet the company's future on genetically-engineered products,
rBGH is the first such product to be marketed. Therefore, it seems unlikely
that Monsanto will voluntarily terminate the uncontrolled IGF-1 experiment
being conducted now on the American people. This is a company that plays
ball. As we saw in REHW #593, Monsanto lawyers frightened Fox TV executives
into killing an investigative series that raised questions about rBGH and
cancer. Just last month Monsanto wrote a threatening letter to Vital Health
Publishing in Bloomingdale, Illinois over the proposed publication of
THE GRAIN, a book by Marc Lappe and Britt Bailey. Monsanto said the new book
would libel its best-selling product, the herbicide Roundup (glyphosate).
Lappe is an established medical writer and an acknowledged health policy
expert. His earlier books include TOXIC DECEPTION (1991), BREAKOUT --THE
Lappe and Bailey run the Center for Ethics and Toxics in Gualala, California
(telephone 707-884-1700). After receiving Monsanto's threats, Vital Health
Publishing abandoned its plans to publish AGAINST THE GRAIN --even though
book had already been printed --for fear of a Monsanto lawsuit, which might
put them out of business even if Monsanto lost in court. Happily, Common
Courage Press (Monroe, Maine; telephone 800-497-3207) will publish AGAINST
THE GRAIN in September. AGAINST THE GRAIN is a detailed account of the
of the new genetic technologies in agriculture. Monsanto's rBGH represents
the tip of a very dangerous iceberg. --Peter Montague (National Writers
Union, UAW Local 1981/AFL-CIO)

=============== [1] Susan E. Hankinson and others, "Circulating
concentrations of insulin-like growth factor I and risk of breast cancer,"
LANCET Vol. 351, No. 9113 (May 9, 1998), pgs. 1393-1396.

[2] Jeff Holly, "Insulin-like growth factor-I and new opportunities for
cancer prevention," LANCET Vol. 351, No. 9113 (May 9, 1998), pgs.

[3] June M. Chan and others, "Plasma Insulin-Like Growth Factor-I and
Prostate Cancer Risk: A Prospective Study," SCIENCE Vol. 279 (January 23,
1998), pgs. 563-566.

[4] C.J. Xian and others, "Degradation of IGF-I in the adult rat
gastrointestinal tract is limited by a specific antiserum or the dietary
protein casein," JOURNAL OF ENDOCRINOLOGY Vol. 146 (1995), pgs. 215-225.

[5] R.K. Rao and others, "Luminal Stability of Insulin-Like Growth Factors I
and II in Developing Rat Gastrointestinal Tract," JOURNAL OF PEDIATRIC
GASTROENTEROLOGY AND NUTRITION Vol. 26, No. 2 (February 1998), pgs.

[6] Toshikiro Kimura and others, "Gastrointestinal Absorption of Recombinant
Human Insulin-Like Growth Factor-I in Rats," THE JOURNAL OF PHARMACOLOGY AND
EXPERIMENTAL THERAPEUTICS Vol. 283, No. 2 (November 1997), pgs. 611-618.

[7] Douglas G.G. Burrin and others, "Orally administered IGF-I increases
intestinal mucosal growth in formula-fed neonatal pigs," AMERICAN JOURNAL OF
PHYSIOLOGY Vol. 270, No. 5 Part 2 (May 1996), pgs. R1085-R1091.

[8] A.F. Philipps, "Growth of artificially fed infant rats: effect of
supplementation with insulin-like growth factor I," AMERICAN JOURNAL OF
PHYSIOLOGY Vol. 272, No. 5 Part 2 (May 1997), pgs. R1532-R1539.

[9] Peter F. Bruning and others, "Insulin-Like Growth-Factor-Binding Protein
3 is Decreased in Early-Stage Operable Pe-Menopausal Breast Cancer,"
INTERNATIONAL JOURNAL OF CANCER Vol. 62 (1995), pgs. 266-270.

[10] J. P. Peyrat and others, "Plasma Insulin-like Growth Factor-1 (IGF-1)
Concentrations in Human Breast Cancer," EUROPEAN JOURNAL OF CANCER Vol. 29A,
No. 4 (1993), pgs. 492-497.

[11] David J. Hunter and Walter C. Willett, "Diet and Body Build: Diet, Body
Size, and Breast Cancer," EPIDEMIOLOGIC REVIEWS Vol. 15, No. 1 (1993), pgs.

[12] See Monsanto's rBGH information at
< where rBGH
is referred to by its trade name, Posilac, or by another name Monsanto
invented for the product, bovine somatotropin or BST.

[13] One of Ms. Shalala's milk ads was reprinted in the BRITISH MEDICAL
JOURNAL Vol. 316 (February 14, 1998), pg. 498. The caption reads, "Donna
Shalala, the United States secretary of health and human services, has been
criticised for her promotion of milk. The milk industry is a powerful lobby
in the US and critics say the endorsement could be the first step on a
slippery slope."

[14] Samuel S. Epstein, "Unlabeled Milk from Cows Treated with Biosynthetic
Growth Hormones: A Case of Regulatory Abdication," INTERNATIONAL JOURNAL OF
HEALTH SERVICES Vol. 26, No. 1 (1996), pgs. 173-185.

Descriptor terms: milk; igf-1; rbgh; bovine growth hormone; monsanto;
carcinogens; breast cancer; prostate cancer; fda; donna shalala; canada;
europe; whole foods; fresh fields; ben and jerry's;



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Pure Food Campaign/SOS (Save Organic Standards)
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