Bioidentical Hormone vs. Non-bioidentical Hormone Replacement Therapy

Bioidentical Hormone vs. Non-bioidentical Hormone Replacement Therapy

Why is it Controversial?


A bit of history is in order to explain this confusing mystery. My involvement in hormonal therapy as a plastic surgeon began when I needed to learn more about the subject for chapters on hormones for my book “Why Grow Old,” which was published in 2010. In addition, I was curious about the subject and have always had an interest in hormones since medical college. The powerful effect of hormones on the human body continues to amaze me.


A flawed study


I was once at a dinner with other couples and the lady next to me, about 50 years old, was fanning herself continuously. She was miserable with her menopausal symptoms of hot flashes and sweating. We began talking and she related to me that her doctor took her off hormones because of a recent study that revealed how hormonal replacement therapy (HRT) caused an increase in cancer and heart disease. The study her doctor was referring to was the Woman’s Health Initiative, a large clinical trial of 16.000 women that was cut short in 2004 because of the substantial increase in heart attacks, strokes, and breast cancer by using the synthetic non-bioidentical hormones, estrogen and progestin. The interpretation of the study was flawed resulting in mistreating thousands of women with menopause.


After reviewing the literature, the study simply proves that synthetic non-bioidentical hormones are harmful. These are quite different from bioidentical hormones. Bioidentical hormones are identical to those our body naturally makes, whereas non-bioidentical hormones are compounds foreign to our bodies.


Statistics relating to unnatural hormones vs. bioidentical hormones:


Unnatural (non-bioidentical) estrogen replacement therapy can cause an increase in blood clotting, especially when given by mouth. In one study, there was an increase in blood clotting by a startling 290% in patients treated with non-bioidentical progestin with estrogen. However, those who were given natural bioidentical progestin in combination with estrogen had a 30% reduction in blood clotting.


In a study of monkeys fed an unhealthy diet, supplemental estrogen decreased the formation of plaques in their arteries (atherosclerosis) by 72% compared to the control group, protecting them from atherosclerosis. The favorable statistics remained the same when the monkeys were given bioidentical progesterone, but when fed non-bioidentical progestin, the protective effects of estrogen was eliminated.


Numerous studies have demonstrated that there is an increase risk of breast cancer with the use of non-bioidentical hormones. One study demonstrated a 40% increase with non-bioidentical progestin and estrogen.  Very worrisome, indeed. However, it appears that bioidentical hormones are associated with a reduction in breast cancer.


The question may arise as to whether one should take either synthetic or natural progesterone at all. A trial study in the International Journal of Cancer in 2004 revealed that premenopausal women with the highest levels of their natural progesterone had an amazing 88% reduction in breast cancer compared to those women with the lowest levels of progesterone. The villain is not progesterone itself, but non-bioidentical progestin. It makes perfect sense and it is backed by a host of studies that supplemental progesterone should be bioidentical, identical to that produced in our bodies, and not unnatural non-bioidentical progestin.


Back to the question, why is it controversial?


The short answer is that doctors and studies, such as the WHI, failed to recognize the difference in bioidentical and non-bioidentical hormones, and the difference is vast. There was a knee-jerk reaction to the flawed study and the results were misinterpreted. The body of scientific evidence indicates that the natural progesterone and estrogen actually helps to protect people from the very diseases caused by unnatural estrogen and progestin.

E. Ronald Finger, MD, FACS

Plastic Surgeon

Savannah, GA

Author Info

E. Ronald Finger MD