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.
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.
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;332:1589-1593.
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;59:1356-1361.
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;123:1615-1622.
4. Hopper JL, Seeman E. The bone density of female twins discordant for tobacco use. N Engl J Med. 1994;330:387-392.
5. Lee JR. Osteoporosis reversal: the role of progesterone. International Clin Nutr Rev. 1990;10:384-391.
6. Prior JC. Progesterone as a bone-trophic hormone. Endocrine Rev. 1990;11:386-398.
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;336:129-133.
9. Barnard ND, Akhtar A, Nicholson A. Factors that facilitate compliance to lower fat intake. Arch Fam Med. 1995;4:153-158.
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;82:129-134.
This article was originally printed under the title Hormone Replacement Increases Cancer Risk in the Autumn 1995 issue of Good Medicine.