Estrogen Does Not Cause Breast Cancer!

Women who take bioidentical hormone replacement (BHRT) feel more energy and vitality while losing weight. Bioidentical hormones are the same ones that your body produces, including estrogen and progesterone. With BHRT, women have improved mood and sleep better. Sexual health is also revitalized, with increased libido. Those benefits are accompanied by overall improvement of health.

Women who take estrogen are much less likely to get heart disease with the risk of heart disease cut in half with estrogen. Also, estrogen actually increases bone density decreasing the risk of osteoporosis and accompanying fractures. This is especially important because of the high risk of death after a hip fracture. Estrogen also is protective against Alzheimer’s disease, especially when starting hormone replacement in the early years of menopause. Women who take estrogen for more than 10 years have significantly reduced incidence of dementia. So heart disease, osteoporosis and dementia , which are the three leading causes of death in women over 70 are all greatly reduced with hormone replacement.

So with all of these benefits, why are so many women apprehensive about taking hormone replacement? The most common reason given is a fear of breast cancer. There are several reasons that estrogen is associated with breast cancer. For one, when a woman is diagnosed with breast cancer, she needs to stop estrogen therapy. This is because estrogen is thought to stimulate the cancer. However, estrogen does not cause cancer. In fact, there is a growing body of evidence that suggests that estrogen actually reduces the risk of breast cancer. While this may sound confusing, estrogen needs to be stopped if breast cancer is diagnosed but multiple studies show that estrogen does not cause breast cancer.

Why is it that women with higher estrogen levels are more likely to get breast cancer? Because women who have increased body fat tend to have higher estrogen levels. This is because an unhealthy type of estrogen called estrone is produced in the fatty tissue. Because of this, even many doctors mistakenly think that it is the estrogen that is increasing the risk for breast cancer. This is not the case. Women who have increased body fat have more inflammation in the body and that is what is increasing the risk for breast cancer and other cancers. Thus, it is the higher inflammation and not the increased estrogen that is putting them at risk. On the other hand, by taking estrogen (especially estradiol), women reduce their body fat which helps reduce body inflammation which can reduce the risk of breast cancer. If you can understand that a high estrogen level is associated with increased risk of cancer because it usually means increased body fat, then you know more about estrogen and its relationship to cancer than most physicians. By reducing body fat, taking estrogen reduces inflammation and thereby reduces the risk of cancer.

Estrogen is commonly prescribed in combination with progesterone. Another cause of the confusion is that the pharmaceutical version of progesterone called Provera is a synthetic drug that has some of the opposite effects of the beneficial progesterone. For example, progesterone is protective against heart disease while Provera negates some of estrogen’s cardiac benefit. Progesterone has positive effects of mood while Provera causes irritability and anxiety.

With regard to breast cancer, progesterone is anti-proliferative and thus protects against cancer. In a large pharmaceutical hormone study (WHI study in 2004), Provera showed a mild increased risk of breast cancer. It should be noted that over time, this increased risk attenuated and there was no increased risk of advanced deadly cancers. Nonetheless, that one finding which did not maintain significance over time, has lead to the conclusion that Provera may cause breast cancer. Unfortunately, many doctors confuse pharmaceutical Provera which has many side effects with bioidentical progesterone which has many beneficial effects including improving sleep and improving mood. Also, progesterone is protective against cancer.

In that same large pharmaceutical hormone study, there was a group that received the pharmaceutical version of estrogen called Premarin, a name derived from “PREgnant MAre’s urINe” because it is derived from horses, without Provera. This group showed NO increased risk of breast cancer. Thus, all this fear of estrogen causing breast cancer has no scientific basis. To the contrary, more studies are emerging that bioidentical estradiol, which is the preferred form of estrogen for hormone replacement, actually reduces the risk of breast cancer.

While Provera showed a slight increased risk of breast cancer, bioidentical progesterone protects against breast cancer. In the lab, progesterone has been shown to inhibit breast epithelial cell proliferation.

Progesterone has anti-proliferative effects on cancer cells inducing apoptosis (cell death) of cancer cells. Synthetic Provera blocks the progesterone receptor sites and breast proliferation occurs with no down regulation to oppose this. This is why it is so frustrating and misleading that so many confuse Provera with progesterone.

Similarly, progesterone protects uterine tissue. Estrogen without progesterone causes proliferation of uterine tissue, which increases the risk of uterine cancer. Fortunately, progesterone protects uterine tissue so when taking a combination of bioidentical estrogen and progesterone, there is no increased risk of uterine cancer. An example of this is when women take tamoxifen for breast cancer, there is increased risk of uterine cancer because the tamoxifen, which has estrogen-like effects, stimulates uterine tissue. Taking progesterone would be protective of the uterus. Similarly, those with PCOS (polycystic ovarian syndrome, which I will be discussing in an upcoming issue), have unopposed estrogen stimulation of uterine tissue and they should be taking progesterone to protect the uterus. It is very important to take oral progesterone rather than using a progesterone cream so the protective levels of progesterone can be reached. Thus, the beneficial effects of hormones are achieved while the breast and uterus are protected.

So by taking bioidentical hormones there is no increased risk of cancer while there are many health benefits including better heart health, better bone health, better brain health and overall feeling great while losing weight. Understanding the literature and the distinction between synthetic and bioidentical hormones is key to understanding the risks and benefits.

Dr. Warren Slaten is a wellness physician specializing in regenerative pain treatments and lifestyle counseling. He is certified in advanced bioidentical hormone replacement. You can learn more on his website, HormonesNJ.com.