THE RISK OF HORMONE REPLACEMENT THERAPY
. . .
by PCRM
The New England Journal
of Medicine of June 15, 1995, reported that hormone
replacement therapy increases the risk of breast cancer.1
This was not news to most
doctors. But many have continued to prescribe hormones
because they feel that the benefits to the heart and bones
outweigh the cancer risk. In the doctor’s mind, it is a
case of “choosing your disease.” Will it be heart disease
and osteoporosis from too little estrogen, or breast cancer
from too much? But before we reach for the prescription
pad, it is worth considering other approaches to menopause
and the problems that sometimes follow it.
Horse Hormones
The
most popular estrogen product is Premarin, from Wyeth-
Ayerst Laboratories. Although doctors sometimes describe
it as “natural” for women, it is actually a horse
estrogen.
On farms in North Dakota and Canada, 75,000 mares are
impregnated and then confined from the fourth month
through the end of their eleven-month pregnancy so
their urine can be gathered in a collection harness.
After they give birth, the mares are reimpregnated.
Their foals usually end up as horse meat, and the
urine estrogens are packed into pills. The trade
name “Premarin” is simply a condensation of the words
“pregnant mares’ urine”—hardly a natural substance
for human beings to swallow. While Premarin contains
estradiol and estrone, two types of estrogen which
are made in humans, it also contains an enormous
amount of equilin, a horse estrogen that never occurs
at all in humans.
Estrogen supplements can have serious side effects.
They are particularly risky for women with clotting
disorders, undiagnosed vaginal bleeding, liver disease,
a past history of breast cancer, or a strong family history
of breast cancer. They increase the risk of uterine cancer,
unless progesterone (or a synthetic progesterone-like drug)
is added to the regimen. They increase the risk of breast
cancer, whether progesterone is added or not. Women taking
estrogen supplements have 30 to 80 percent more breast
cancer risk than other women. So why are so many doctors
prescribing them? Most of the push relates to osteoporosis
and heart disease. Osteoporosis is very common in Caucasian
women, less so among other races. About one-quarter of
white women over 60 have compression fractures of their
vertebrae, and many develop hip fractures due to the gradual
loss of bone. But estrogens are not nearly as good at protecting
the bones as women may be led to believe, and they rarely
arrest bone loss. At their best, estrogens simply slow
the rate of bone deterioration.
Other
approaches can be much more effective, and they do
not cause cancer. For example, a major article in
the
American Journal of Clinical Nutrition reported last
year that eliminating animal protein from the diet
can cut urinary calcium losses in half,2 resonating
with other studies showing that populations that
follow plant-based diets have enviably low rates
of hip fracture. Cutting salt intake can reduce your
calcium losses even further.3 Limit your caffeine
consumption to no more than two cups of coffee per
day, and you will hold onto still more calcium. If
you don’t smoke, you’ll also avoid the 10 percent
loss of bone that plagues chronic smokers.4 If you
put these factors together, they are a powerful and
safe approach for strong bones.
When osteoporosis has developed, a different hormone,
called natural progesterone, has demonstrated the ability
to actually encourage new bone growth. Unlike estrogens,
which simply slow bone loss, progesterone actually increases
bone density.5-7 It is derived from yams or soybeans, has
no significant side effects, and is sold without a prescription
as a transdermal cream. For more information, call Professional
and Technical Services (800-648-8211), Women’s International
Pharmacy (800- 279-5708), or Klabin Marketing (800-933-9440).
For heart disease, hormones are no match for lifestyle
changes. As Dr. Dean Ornish’s pioneering work has shown,
a
combination of a low-fat vegetarian diet, mild exercise,
stress reduction, and smoking cessation is powerful
enough to actually reverse heart disease in 82 percent
of patients in one year.8 But Americans want pills, and
they don’t want to change their diets, say some doctors.
The truth is, many people will gladly change their diets
and other aspects of their lifestyle if they understand
the benefits of doing so and are assisted in the process.9
The real problem is, even though a mountain of research
has shown the value of dietary and lifestyle approaches,
many doctors still know little= about them.
Of course, it is not just estrogen pills that increase
cancer risk. Estrogen production within a woman’s body
is increased by high-fat diets and overweight. The result
is a higher risk of cancer. The National Cancer Institute
reports that cutting fat to 20 percent of calories will
reduce a woman’s estrogen levels by 17 percent, which is
a good first step in cancer prevention.10
There Is No Japanese
Word For Hot Flashes
It
has long been known that menopause is much easier
for Asian women than it is for most Westerners. Hot
flashes are reported by only about 10 percent of
Japanese women at menopause. Not only are hot flashes
much rarer, but bone strength is not assaulted to
the extent it often is among Western women. Broken
hips and spinal fractures are much less common. The
most likely explanation is this: throughout their
lives, Western women consume much more meat and about
four times as much fat as do women on traditional
Asian rice-based diets, and only one-quarter to one-half
the fiber. The result is a chronic elevation of estrogen
levels. At menopause, the ovaries’
production of estrogen comes to a halt, causing a violent
drop in estrogen levels. Asian women have lower levels
of estrogen both before and after menopause, and the drop
appears to be less dramatic. The resulting symptoms are
much milder or even non-existent. Those who enter menopause
on a low-fat vegetarian diet often breeze right through
it. This does not mean that women who have more symptoms
have somehow
failed, but it is a good reason to learn about how
foods can affect this aspect of health.
References
1. Colditz
GA, Hankinson SE, Hunter DJ, et al. The use of estrogens
and progestins and the risk of breast cancer in postmenopausal
women. N Engl J Med 1995;332:1589-93.
2. Remer T, Manz F. Estimation of the renal net acid
excretion by adults consuming diets containing variable
amounts of protein. Am J Clin Nutr 1994;59:1356-61.
3. Nordin BEC, Need AG, Morris HA, Horowitz M. The
nature and significance of the relationship between
urinary sodium and urinary calcium in women. J Nutr 1993;123:1615-22.
4. Hopper JL, Seeman E. The bone density of female
twins discordant for tobacco use. N Engl J Med 1994;330:387-92.
5. Lee JR. Osteoporosis reversal: the role of progesterone.
International Clin Nutr Rev 1990;10:384-91.
6. Prior JC. Progesterone as a bone-trophic hormone.
Endocrine Rev 1990;11:386-98.
7. Prior JC, Vigna Y, Alojado N. Progesterone and
the prevention of osteoporosis. Canad J Ob/Gyn 1991;3:178.
8. Ornish D, Brown SE, Scherwitz LW, et al. Can lifestyle
changes reverse coronary heart disease? Lancet 1990;336:129-33.
9. Barnard ND, Akhtar A, Nicholson A. Factors that
facilitate compliance to lower fat intake. Arch Fam
Med 1995;4:153-8.
10. Prentice R, Thompson D, Clifford C, Gorbach S,
Goldin B, Byar D. Dietary fat reduction and plasma
estradiol concentration in healthy postmenopausal women.
J Natl Cancer Inst 1990;82:129-34
This article
was originally printed under the title Hormone Replacement
Increases Cancer Risk in the Autumn 1995 issue
of Good Medicine.