Are they safe? What's the risk compared to synthetic HRT?

Fortunately, the realization that hormone replacement therapy (HRT) was causing breast cancer, and the subsequent decrease in use of artificial hormones, has led to a 37 percent reduction in death rates among women (according to a report published in the July/August issue of CA: A Cancer Journal for Clinicians.)

Are Bioidentical Hormones Safe?

Bioidentical hormones (like estrogen and progesterone) are created by compounding pharmacies to relieve the symptoms of menopause and hormonal imbalances. They are made from ingredients derived from plants such as yams and soy and have been available for more than 20 years. Bioidentical hormones have never been associated with the dangers of Premarin and synthetic progestins like the ones uncovered in the Women's Health Initiative (WHI), and it is likely that they never will be, as they are natural human hormones.

Concludent studies like the one published in a 2007 issue of Breast Cancer Research reported that bioidentical hormones are superior to synthetic hormones, and there is no risk of developing breast cancer, while synthetic versions significantly increase the risk of breast cancer. This study found that women who used estrogen only or a synthetic progestin in combination with estrogen had a significant increase in the risk of breast cancer.

If, however, a woman used natural progesterone in combination with estrogen, the increased risk of breast cancer was eliminated. In addition, estriol containing products were found to have a further protective effect against breast cancer.

"A thorough review of the medical literature clearly supports the claim that bioidentical hormones have some distinctly different, often opposite, physiological effects to those of their synthetic hormones. The medical literature demonstrates that bioidentical hormone replacement therapy is highly effective and carries a reduced, rather than an increased risk of breast cancer and cardiovascular disease." (Dr. Kent Holtorf)

In January, 2009 Holtorf Medical Group performed a comprehensive analysis of over 200 physiological and clinical studies (including the WHI study) concerning synthetic and bioidentical hormones. This analysis looked at the many long-term and short-term studies of synthetic hormones and the short-term studies of bioidentical hormones. To date, there have been no long-term studies of bioidentical hormones, but each short-term study shows positive results both in the relief of symptoms of hormonal imbalances like insomnia, cognitive problems, depression, anxiety, etc. and in the decreased risk of heart disease and breast cancer. Meanwhile, both long-term and short-term studies show synthetic hormones to be less effective at treating symptoms and to increase the risk of breast cancer and cardiovascular disease.

Does the FDA And Other Affluent Organizations Dictate The Rules?

In January 2008 the Food And Drug Administration (FDA) banned estriol, the bioidentical estrogen, being concerned about its effectiveness and safety. But estriol has been used for the past 30 years with no report of an adverse symptom. FDA's claims were related to the lack of evidence that it was safer than the synthetic versions and because there was no standardized dose. Fact is that clinical reality and solid studies have proven already that standardized, one-size-fits-all dosages and approaches don't work on all metabolisms.

Dr. Kent Holtorf of the Holtorf Medical Group states that more and more mainstream doctors, "are now realizing that societies such as The Endocrine Society, The North American Menopause Society and The American College of Obstetricians and Gynecologists (ACOG) have either failed to adequately review the medical literature on bioidentical hormones or more likely have let their significant relationships with the pharmaceutical companies influence their positions on the issue."

Here is another statement by Dr. Eldred Taylor that supports this belief: "As a board certified, OB/GYN trained at Emory University, I am embarrassed by what I learned in residency concerning hormone physiology. It is a crime that this information is not taught in residencies. Instead we are bombarded by propaganda and misinformation by the so-called leaders in our field."

However, there are some potential dangers to using bioidentical hormones if they are not prescribed by someone who is very knowledgeable in this area. If one simply measures female hormones and then supplements with bioidentical hormones, most likely they will not do better. You can avoid this if you seek out a qualified, well-trained individual.


Unequal risks for breast cancer associated with different hormone replacement therapies: results from the E3N cohort study. Fournier A, Berrino F, Clavel-Chapelon F. Breast Cancer Research and Treatment 2007

Breast Cancer and BHRT

Holtorf, Kent. The Bioidentical Hormone Debate: are Bioidentical Hormones (estradiol, estriol, and Progesterone) safer or More efficacious than Commonly used synthetic Versions in Hormone replacement therapy?

The Real Reason Why Breast Cancer is Plummeting

Are Bioidentical Hormones Safe?

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