How Safe and Effective Are Bioidentical Hormone Therapies?

By Guest Contributor |

by Tara Haelle

The popularity of bioidenticals has surged over the past decade, particularly among women with safety concerns about hormone therapy (HT) during and after menopause. Yet many women may not realize how little research exists on these products’ safety, effectiveness, purity, strength, or quality.

Bioidenticals are hormones derived from plants and/or synthetically produced or altered to have a similar chemical structure as hormones produced by the body. They may also contain FDA-approved hormone products. Bioidenticals can be ordered online or compounded at pharmacies using a healthcare provider’s instructions, but the FDA does not regulate most of these products because they’re considered supplements. The agency leaves regulation of compounded formulations with FDA-approved products to the states. Little to no regulation controls bioidenticals’ production and distribution.

Women typically choose to use bioidenticals to manage the menopause symptoms that HT treats. Menopause causes women’s bodies to make less estradiol, the estrogen responsible for maintaining bone mass and vaginal tissue. Lower estradiol levels increase risks of osteoporosis and bone fractures and often lead to vaginal atrophy. HT therefore involves taking estradiol to replace what women’s bodies aren’t making. Women who still have a uterus also take progesterone to reduce the risk of endometrial cancer. (Estradiol by itself can cause abnormal cell growth in women without hysterectomies.)

However, the large Women’s Health Study raised concerns about HT. The study investigated HT’s safety and effectiveness but was cut short because it became quickly apparent that HT increased risks of heart disease and breast cancer, though the study also found HT reduced risks of colorectal cancer, bone fracture, and osteoporosis. The consensus of healthcare professionals is that women should individually assess HT’s risks and benefits for their particular situation with their doctor.

Many women concerned about HT risks have opted for bioidenticals, which include forms of estradiol, estrone, and estriol estrogens plus progesterone optimized (“micronized”) for better absorption. Past surveys found one of the biggest reasons women choose bioidenticals is their belief that the products are natural or made “without chemicals.” Unfortunately, though, that’s not the case. Even plant-derived bioidenticals are usually altered in the laboratory to make them similar to human hormones, and all of them are made up of chemicals.

The term “bioidentical” is a marketing term rather than a scientific one, explains the American College of Obstetricians and Gynecologists (ACOG). The hormone therapy products approved by the FDA come from both plant and animal sources and are equally “natural” as bioidentical products. The biggest difference between FDA-approved hormone therapy products and bioidenticals is that bioidenticals are unlicensed and not tested for safety or effectiveness. Unlike FDA products, bioidenticals also aren’t tested for purity and consistent potency.

Women may also choose bioidenticals for their individualization. For example, a doctor may prescribe a compounded formulation instead of an FDA-approved product containing peanut oil if the woman has an allergy. Beyond these cases, however, “hormone customization is very difficult to achieve because blood hormone levels are difficult to measure and regulate accurately due to normal physiologic variations,” the Endocrine Society wrote in their statement on bioidenticals.

Some providers use saliva or blood tests to assess hormone levels, but research has shown these tests are unreliable and cannot accurately measure levels. Further, the body cannot tell the difference between bioidentical hormones and ones made by the body, so tests cannot tell how much bioidenticals are absorbed. Some bioidenticals even use plant sources, such as Mexican wild yam, that produce estrogen the human body isn’t capable of using. Because these levels cannot be tested and the products aren’t tested, women can also receive underdosage or overdosage. Overdosage can increase the risk of abnormal endometrial cell growth, endometrial cancer, and blood clots.

In fact, the biggest concern with bioidenticals is safety. One survey found 71% of women believe “natural hormones” have fewer or no risks and 69% thought they had fewer or no side effects. Yet bioidenticals haven’t been studied enough to show safety. Chemically, they would be expected to have the same risks as FDA-approved hormone therapies — but they aren’t required to carry the same black-box warnings as FDA products, even if the risks are the same.

Neither ACOG nor the Endocrine Society say women shouldn’t take bioidenticals. Both organizations emphasize the importance of informing women of the risks and lack of scientific evidence for bioidenticals’ safety and effectiveness, and both call for greater regulation of these substances, especially given their continued popularity and similar risks to hormone therapy.   

An earlier version of this article was published in the spring 2017 DES Action USA newsletter.

7 Comments

  1. lissa says:

    Great. I am suffering with Hormone issues since long period of time. I tried several treatments, home remedies, precautions but nothing works. I never tried and heard about these Bioidentical hormone therapies. Would definitely try it.

  2. Sharon says:

    I appreciate your article and all objective information I can never have too much. As an energetic lady with an amazing memory, I began feeling awful, tired and thought I had early dementia at 48. It was menopause.I did tons of research and read about the 1939 development of HT at the Univ of Georgia & other internal ‘work product’ memos on why Pharma can’t patent it, so health ins. won’t reimburse women because its experimental – 78 years later? (Bull!) and its expensive. Yet, I still get my pellets (12 yrs now) updated 2X a year now and always will! I swear by my estradiol soy pellets. My backside is scarred now but that’s OK. Thanks again for your article.

  3. shaaron says:

    I have been using bio-identical hormones for about 4 years now. I use estradiol, progesterone and pregnenolone over the counter creams, regularly. This has helped me recover from a brutal menopause which included male pattern baldness and increased body fat due to a slow metabolism. I do worry about safety as you can never find enough safety study information but believe this is a good path.

  4. Elaine L. says:

    I would ask for a review of this article by a prescribing OB/GYN. It mixes some valid points (for example, the variable quality– from excellent to problematic– in the Wild-West world of compounding pharmacies) with some problematic conflations. For example, I’d point to this paragraph:

    “Some providers use saliva or blood tests to assess hormone levels, but research has shown these tests are unreliable and cannot accurately measure levels. Further, the body cannot tell the difference between bioidentical hormones and ones made by the body, so tests cannot tell how much bioidenticals are absorbed. Some bioidenticals even use plant sources, such as Mexican wild yam, that produce estrogen the human body isn’t capable of using.”

    Problem: Lumping together blood tests (which are generally accurate, but sometimes hard to interpret) with saliva tests (which useful for testing some things but not others).

    Second problem: It’s not very helpful to point out that the body registers hormones in the body and hormones taken the same and imply that that’s an issue. The whole point is that low menopausal levels can cause symptoms– so if one measures low estrogen levels in menopause, for example, and then slightly higher levels after supplementation, it’s pretty obvious what’s going on.

    Third problem: Are you really talking about people taking Mexican wild yam, or conflating that with the wild yam that was used as a chemical building block in the lab (since the 1960’s) for hormones, including the same hormones in FDA-regulated products?

    Thank you for pointing out the legitimate concerns about this Wild West area of medicine. There’s some scary stuff out there, such as the Wiley Protocol. But OBOS does women a disservice by tarring all compounded hormones with the same brush.

    Recommended reading for more accurate information: “The Idiot’s Guide to Bioidentical Hormones” By Dr. Ricki Pollycove, or, for more detail, “Outliving Our Ovaries” by Dr. Marina Johnson.

  5. me heck says:

    I find this hilarious in some ways. Articles like this always state the FDA hasn’t tested the products. What most people don’t know is that the FDA does absolutely NO TESTING! The companies who apply for approval from the FDA PAY for studies (no governmental) and give the FDA the outcomes of those studies. Government lies again!

    • Bigswoll7 says:

      I agree with your comment on the FDA1 people seem to think that the FDA voice should carry weight. Perhaps at one time but anymore the FDA will say and print whatever they are told by Pharm companies. I had a teacher in college that said to this and I never forgot it “Statistics don’t lie but liars use statistics!” meaning no matter what the data is the FDA gets they spin it so it comes out just as the company request.

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