Estrogen Therapy Can Reduce Breast Cancer Risk

STEP INTO THE SPOT LIGHT with Teresa Sievers, MD, MSMS, FAARM and Karen Callan BA, CHHC, AADP

Dear Dr. Sievers,

I am 55 years old.  I understand that with menopause, and of course, just aging in general, that things will change in my body. Recently I read something about estrogen therapy alleviating some of the common menopausal issues I’m having, but I’m concerned about risks of breast cancer. Also, I had a hysterectomy five years ago, but still have my ovaries. Am I even a candidate for hormone therapy?
– Melanie

Dear Melanie,
Estrogen provides over 400 functions that are responsible for maintaining the body’s overall health. The effects a woman experiences with estrogen loss has wide spread consequences throughout the entire body. And while the symptoms associated with estrogen loss can greatly affect quality of life, more importantly the loss of estrogen can cause significant health risks. These risks include: bone loss, increased cholesterol levels and blood pressure, insulin resistance creating increased risk for diabetes, heart disease and breast cancer.

Estrogen therapy in the form of bio identical hormone replacement therapy (BHRT) has shown to not only alleviate the symptoms associated with estrogen loss, but in fact, can reduce the risk of breast cancer. However, like many women, you have only heard one side of the story, so it’s important to address those concerns and shed some light on the benefits of estrogen BHRT.

Commonly discussed as a single hormone, the body makes three main estrogens:  estrone-E1, estradiol-E2 and estriol-E3. Like all hormones, estrogen hormones are enabled by fitting into a specific receptor, like a key fitting into a key hole. Each of these estrogens stimulates two estrogen receptors in different ways in order to perform specific functions in the body. But one of the receptors stimulates breast tissue more than the other, which can attribute to increased risk of breast cancer. For simplicity, we will call them good and bad estrogen receptors.

In order to maintain bone health, estrone serves as a reservoir to convert to estradiol, which is responsible for diverse functions. Estradiol also increases good cholesterol (HDL) and decreases bad cholesterol (LDL), maintains memory and decreases blood clotting. It also increases the growth hormone, known as the “fountain of youth” hormone. Loss of estradiol will adversely affect those functions.

But estrone and estradiol also stimulate the bad receptors. While estradiol stimulates the good and bad receptors equally, estrone stimulates the bad receptors five times more than it does the good receptors. This is not a concern prior to menopause. But during menopause, the estrone production increases by 80% becoming the predominant estrogen. And even though the ovaries stop working estrone is still produced in fat tissue and adrenals.

Estriol plays an important role protecting the breast from over stimulation of breast tissue by blocking estrone and estradiol and it also stimulates the good receptors three times as much as the bad. It has been used in Europe for over 60 years to prevent breast cancer. In fact, low levels of estriol are known to be associated with an increase risk of breast cancer.

Most women are hearing about the risk of breast cancer from the media. But the information they hear is likely from the WHI study that showed an increased risk of breast cancer in women who took synthetic estrogen with synthetic progestin, not BHRT.

It’s also important to note the study used synthetic estrogen made from horse urine (Premarin) which is 50% like estrone! Yet large scale trials of over 23,000 women showed that women receiving estradiol or estriol BHRT revealed a 28% decrease in the risk of death from breast cancer.

Essentially, the risks of breast cancer increases during menopause because of the imbalances of the estrogen. And as discussed in previous articles, menopause also causes a decrease in progesterone, which also has a protective effect on the breast from the over production of estrogen.  Women need to be aware that not taking any hormones can cause the breasts to not only be excessively stimulated by estrone, but also unprotected as there is not ample progesterone to balance the estrone. This creates a ripe environment for breast cancer. Even a woman who has had a hysterectomy still requires progesterone therapy when taking estrogen.

BHRT is only a one part of treatment plan in reducing the risks of breast cancer. Analyzing how estrogen is metabolized in the body is critical component of BHRT and it should be tested even if a woman is not undergoing BHRT. A further discussion of how improper estrogen metabolism can create an environment in the body for cancer will be discussed in next article.

Teresa A. Sievers,
Restorative Health & Healing Center
10201 Arcos Av., Suite 201, Estero
Learn more about Dr. Sievers at:

Karen R. Callan, CHC, AADP
Certified Health Coach
10201 Arcos Ave., Suite 201 Estero
Learn More About BEST BODY NOW at:

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