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Estrogen Dominance Linked to Cancer
by Catherine P. Rollins

Breast cancer is a major health issue. It is the most common cancer-related cause of death in women in Australia. One in twelve Australian women will develop the disease and each year many women die from it.

World-wide about 1,670,000 women have breast cancer. And in North America, a woman dies of breast cancer every 12 minutes!

Your risk of surviving malignant breast cancer is just about the same as it was 50 years ago, when the only treatment was mastectomy; about one in three. The incidence of breast cancer is steadily rising and the numbers are appalling. Between 1973-1998 the incidence of breast cancer rose by over 40%.

Ovarian cancer is particularly scary because by the time it's detectable, in 70 to 80 percent of women it has already spread to other parts of the body and thus has a high mortality rate. It accounts for nearly 20 percent of gynecologic cancers, and it ranks fifth in cancer fatalities in women. Most ovarian cancer occurs in menopausal women around the age of fifty.

Uterine cancer, also known as endometrial cancer, is not as common as ovarian cancer. Generally, endometrial cancer develops during the pre-menopausal years when high levels of estrogen and low levels of progesterone are present. The only known cause of endometrial cancer is unopposed estrogen.

Cancer of the cervix is the second most common cancer in women worldwide and is a leading cause of cancer-related death in women in underdeveloped countries. Worldwide, approximately 500,000 cases of cervical cancer are diagnosed each year.

Oral contraceptives have been linked to both endometrial and cervical cancers.

Prostate problems are the fastest-growing health concern among men in Western countries, and the rate of prostate cancer is increasing steadily.

The initiation of normal cells turning into cancer cells is the same for both the breast or uterus and the prostate gland. In these organs, cancer initiation is due primarily to estrogen dominance combined with lifestyle factors and/or toxic insults that predispose estrogen to become oxidised.

The incidence of prostate cancer increases with age. The majority of men in the US will acquire prostate cancer if they live beyond 65. It is a slow-growing cancer (more rapidly growing in younger men, however). For men over 65, the doubling time of a prostate cancer nodule is usually about 5 years. Compare this with the doubling time of a breast cancer nodule, which is about 3 to 4 months. If left untreated, prostate cancer tends to eventually metastasize to bones.

Some of the risk factors for cancer, such as race, age, and family history, are out of your control, so the bottom line in minimising your risk of cancer is to lead a healthy lifestyle, use your common sense, and avoid excess estrogen, whether it be from pesticides, synthetic HRT, or oral contraceptives.

What is estrogen dominance?

We are now learning that many of these cancers are all known to be a result of hormonal imbalances. Specifically they are a result of excess estrogen or estrogen dominance.

Estrogen dominance is a term coined by the late Dr John Lee in his first book on natural progesterone. It describes a condition where a woman can have deficient, normal, or excessive estrogen but has little or no progesterone to balance its effects in the body. Even a woman with low estrogen levels can have estrogen-dominance symptoms if she doesn't have any progesterone.

And how do we become 'estrogen dominant'?

All too often our food chain is laced with toxic pesticides, herbicides and growth hormones – a sea of endocrine-disrupting chemicals that mimic estrogen in our body. If we are overweight, our body’s store of excess fat can be converted into estrogen. Insulin resistance leads to estrogen dominance. A visit to our GP for the odd hot flash, missed period or PMS discomfort can result in a prescription of estrogen pills, patches or implants.

And yet unopposed estrogen in our bodies results in all sorts of hormone-related health problems such as PMS, endometriosis, uterine fibroids, infertility, weight gain, increased blood clotting, thyroid dysfunction, even cancer, in both men and women.

Our men-folk are equally at risk. Estrogen gradually rises as men age, while saliva levels of progesteorne and testosterone gradually falling. Thus, with aging, estrogen dominance occurs. A clear sign of estrogen dominance in aging men is their tendency to develop breasts. This indicates these men are low in progesterone and testosterone.

Where does progesterone fit in?

Estrogen is the hormone that stimulates cell proliferation, or the growing phase. In other words, estrogen causes cells to divide and multiply. Progesterone, on the other hand, is the hormone that stops growth and stimulates ripening. It induces cell maturation and programmed cell death (called apoptosis).

Although cells in different parts of the body may look and work differently, most repair and reproduce themselves in the same way. Normally, this division of cells takes place in an orderly and controlled manner. If, for some reason, the process gets out of control, the cells will continue to divide, developing into a lump which is called a tumour. Tumours can be either benign or malignant. Doctors can tell whether a tumour is benign or malignant by examining a small sample of cells under a microscope. This is called a biopsy.

Whilst not a cure for cancer, progesterone can dramatically decreases cell multiplication rates, providing women with a degree of protection against estrogen-driven cancers. Normal levels of progesterone in the body can, therefore, actually help protect you against some forms of cancer.

We know now that progesterone deficiency is linked to an increased risk of cancer. Uterine cancer, for example, is known to be caused by unopposed estrogen. That's why women who have an intact uterus and take estrogen replacement therapy must also be given some form of progesterone to oppose estrogen and reduce this risk. This is generally given in the form of synthetic progestin which, incidentally, is not the same molecule as bioidentical progesterone, but is designed to block estrogen effects.

The evidence against estrogen is stacking up

According to Dr Cavalieri, Professor at the Eppley Institute for Research in Cancer and Allied Diseases at the University of Nebraska Medical Centre in Omaha Nebraska, he and his team are at the brink of discovering that almost all the important human cancers that we get in Western civilisation, have the same origin, which is estrogen.

Estrogens, according to Dr Cavalieri, are initiators and promoters of cancer.

They are initiators because they form cancer-causing agents, by metabolising in a specific way. After that they promote cancer via these receptor-mediates processes that increase cell proliferation.

All the evidence, according to Dr Cavbalieri, implicated estrogens (including the natural hormones estradiol and estrone), as a major cause of breast cancer [National Cancer Institute Monograph #27, Oxford University Press]. Therefore, if you use progesterone cream and avoid having extra estrogen in the body, you avoid the initiating process.

For women, cancer of the breast and/or in the uterus most often occurs with a progesterone (P) to estradiol (E2) ratio of less than 200 to 1. According to Dr David Zava of ZRT, who has amassed a database of tens of thousands of saliva samples and questionnaires, these cancers occur very rarely in women with a healthy P/E2 ratio.

The Johns Hopkins University conducted a 20 year study, published in 1983 in the American Journal of Epidemiology, showing that women who had good progesterone levels had less than a fifth of the amount of breast cancer, and less than a tenth of all the cancers that occurred in women who were low in progesterone. These outcomes suggest that having a normal level of progesterone protected women from nine-tenths of all cancers that might otherwise have occurred.

Molecular biologist, Dr. Ben Formby of Copenhagen, Denmark and Dr. T.S. Wiley at the University of California in Santa Barbara have researched two genes, BCL2 and P53, and their effect on female-specific cancers and prostate cancer.

Cells of breast, endometrium, ovary and prostate, were grown in the laboratory. Estrogen (estradiol) was added to the cells. This hormone turned on the BCL2 gene, causing the cells to grow rapidly and not die. Then, progesterone was added to the cell cultures. Cell reproduction stopped and the cells died on time (apoptosis).

This methodology was applied to all the above types of cancer. The BCL2 gene, therefore, stimulates the growth of these cells and the risk of cancer. On the other hand, the P53 gene promotes apoptosis or programmed cell death and thereby, reduces the risk of cancer. Estradiol upregulates or stimulates the production of the BCL2 gene, while progesterone upregulates or stimulates the production of the P53 gene.

Drs de Lignières and Chang sort to measure the rate at which breast cells multiplied. The breast cells chosen were the milk duct cells since these are the cells where cancer originates in breasts.

Keep in mind that a cancer cell differs from a normal cell in only two ways: (1) it multiplies faster and (2) it hasn't differentiated and become developed into the full mature cell that it is suppose to.

Controlled tests indicated estradiol raised the cell proliferation rate over 200%, progesterone with estradiol brought it back to normal. The ones with progesterone only, lowered the proliferation rate by 400%. The authors concluded that they had shown that estrogen is truly a stimulant of breast cancer and progesterone is a protector of breast cancer.

Therefore natural progesterone decreases the risk for several types of cancer, while unopposed estradiol causes these same types of cancer.

In cases of hormone dependent cancers, it is critically important to maintain optimal levels of natural progesterone and avoid the factors that would promote too much estradiol.

Friend or foe

Just as there is no one apple called apple, there is no one estrogen named estrogen. The word estrogen refers to a class of THREE estrogens as follows:

  • Estrone
  • Estradiol
  • Estriol

Among the three major natural estrogens, estradiol is the most stimulating to breast tissue, estrone is second, and estriol by far the least. And since all estrogens compete for the same receptor sites, it is probable that sufficient estriol impedes the carcinogenic effects of estradiol and/or estrone.

Low levels of estriol relative to estradiol and estrone appear to correlate with increased risk of breast cancer, while higher levels of estriol from endocrine treatment correlate with remission of cancer.

It is now believed that the two major hormones present throughout pregnancy - progesterone and estriol - could may well offer protection against breast cancer.

Does progesterone increase my risk for cancer?

According to the late Dr Lee, two studies published in the American Journal of Pathology in 1999 show that estrogen increases breast and prostate cancer, and that progesterone receptors in the breast and prostate are more abundant in cases of more agressive cancer. Misinterpretation of this type of result is common.

Conventional interpretation suggests that this might indicate that progesterone causes the more aggressive breast and prostate cancers. The truth is that progesterone receptors are made by estrogen. The higher the estradiol/progesterone ratio, the greater are the number of progesterone receptors that will emerge.

This is the tissue's effort to restore proper progesterone function in situations where estrogen dominance is present. Thus, increase of progesterone receptors is evidence of estrogen dominance, and not evidence that progesterone increases the risk of cancer.

Synthetic HRT and Cancer

Researchers stopped a large study of synthetic HRT in July 2002 when it became clear the therapy increased the risk of heart disease, cancer and blood clots. A number of studies since then have supported those results.

The Women's Health Initiative study was stopped short one year ago when it became clear that estrogen-progestin increased the risk of breast cancer, heart attack, and strokes. But research using the data from that study goes on, and the latest findings are nothing less than a disaster.

Examining records of more than 16,000 women, researchers concluded that combined HRT tends to make breast cancer tumors more aggressive and harder to detect, reducing the chances for successful treatment.

The Million Women Study, of whom about half used or had used HRT, indicated for the first time that the increased risk started between one and two years of HRT use, dashing any suggestion that increased cancer risk only developed after long-term use. But the risks grew larger the longer the HRT treatment continued.

The biggest blow dealt by the Million Women study, the results of which are published in the Lancet medical journal, was to combination estrogen and progestin therapies, taken by about half of all those on HRT in the study. These doubled the breast cancer risk. They are widely used, because estrogen-only therapies are known to increase cancer of the womb-lining.

Chemically-altered hormones can shut down or reduce our production of natural hormones. Because the molecules have been changed, the synthetic hormones used in the Contraceptive Pill and HRT do not have the same effect on the mind and body as our natural hormones do. In fact, many of the effects of synthetic hormones are the exact opposite to the natural hormone they so ineptly replace.

One prime example of HRT's 'unnatural' molecular makeup is in the case of medroxy-progesterone acetate, a synthetic progestin. If used during pregnancy, this progestin has the potential to cause birth defects.

Natural progesterone, however, being bioidentical to the body, is routinely used in fertility clinics around the globe to help sustain pregnancy in high-risk situations.

Getting progesterone back into your body

A couple of things to consider here. Firstly, statistics clearly tell us that conventional medicines for treating cancer such as tamoxifen, radiation, and chemotherapy just aren't working in the long run. Secondly, new emerging research is providing clear evidence that estrogen without progesterone is a setup for many reproductive cancers. And, finally, if we're going to supplement hormones, we want to keep in mind that our body will respond best to hormones chemically identical to those which the body naturally produces.

That being the case, and all things considered, perhaps identifying and restoring hormone balance might yet offer a logical starting point in fighting these cancers.

And the easiest and safest way to bring our progesterone to estradiol levels back within a ratio of 200~300:1, thereby protecting us against this potentially life-threatening state of hormone imbalance, is by using a premium quality controlled natural progesterone cream in conjunction with regular salivary hormone profiles.

These natural progesterone creams are extremely safe to self-medicate, are non-toxic, and free of side-effects because they contain USP grade micronised progesterone which is essentially the same molecule naturally occurring in the body.

About the Author:

Catherine P. Rollins is the author of 'A Woman's Guide to Using Natural Progesterone' and Director of the highly popular website:

This article was syndicated from The Natural Progesterone Advisory Network:


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