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Endocrine FunctionWomen’s Health

Isoflavones, Compounded Bioidentical Hormones, and the Alleviation of Menopausal Symptoms

December 21, 2017

by Dr. Mark Messina

Soyfoods and the isoflavones isolated from soybeans, which are available in supplement form, are one of several nonhormonal treatments for hot flashes. These types of “alternative treatments” are especially popular among women, who for any number of reasons, have decided not to use conventional hormone therapy (HT). Interest in alternatives to HT has increased as interest in HT has decreased. Many women began to sour on HT as a result of the findings from the Women’s Health Initiative Trial published in 2002.1 This trial, which involved over 10,000 women, found that the harms of HT outweighed the benefits.

Considerable research shows isoflavones significantly alleviate hot flashes reducing frequency by approximately 50% to 60%.2 Although not as potent as HT,3 despite a very recently published study involving over 300 women suggesting they are,4 isoflavones are still going to markedly improve the quality of life of women suffering from hot flashes. However, despite the impressive data, many women who shunned HT have opted for compounded bioidentical hormones (cBHT) rather than isoflavones to alleviate their menopausal symptoms. According to a 2016 survey of American pharmacists, an estimated 26 to 33 million cBHT prescriptions are filled annually with total sales estimated at $1.3 to $1.6 billion.5

Here is some background information on cBHT that might be helpful: Simply put, bioidentical hormone preparations are medications that contain hormones that are an exact chemical match to those made naturally by humans. Some bioidentical hormones are made by drug companies and approved by the FDA. However, other bioidentical hormone preparations are made at special pharmacies commonly referred to as compounding pharmacies, which make the preparations on an individual basis for each patient. Those “custom-made” preparations aren’t approved by the FDA.

In a recent viewpoint published in JAMA Internal Medicine, Stuenkel, and Manson6 emphasize that evidence in support of the efficacy and benefits of cBHT is lacking. Similarly, they note that safety data are lacking. An additional concern is the lack of standardization for cBHT in that analyses have shown there is substantial variation in the content of cBHT products.7 This variation is worrisome because, for example, inadequate progesterone administration to women taking estrogen therapy increases risk of developing endometrial cancer.

Not surprisingly, virtually every medical society that provides guidance to clinicians treating women who are perimenopausal and postmenopausal recommends against prescribing cBHT.6 Nevertheless, cBHT is often perceived as natural and therefore safer than FDA-approved products, although this belief is not supported by evidence.7

Every woman needs to decide for herself which treatment for menopausal symptoms makes most sense. Certainly, based on a wealth of data, soybean isoflavones should be a highly considered option for women suffering from hot flashes.

References

  1. Rossouw JE, Anderson GL, Prentice RL, et al. Risks and benefits of estrogen plus progestin in healthy postmenopausal women: principal results From the Women’s Health Initiative randomized controlled trial. JAMA. 2002;288:321-33.
  2. Taku K, Melby MK, Kronenberg F, Kurzer MS, Messina M. Extracted or synthesized soybean isoflavones reduce menopausal hot flash frequency and severity: systematic review and meta-analysis of randomized controlled trials. Menopause. 2012;19:776-90.
  3. Crisafulli A, Marini H, Bitto A, et al. Effects of genistein on hot flushes in early postmenopausal women: a randomized, double-blind EPT- and placebo-controlled study. Menopause. 2004;11:400-4.
  4. Tit DM, Pallag A, Iovan C, Furau G, Furau C, Bungau S. Somatic-vegetative symptoms evolution in postmenopausal women treated with phytoestrogens and hormone replacement therapy. Iranian Journal Public Health. 2017;46:1528-34.
  5. Pinkerton JV, Constantine GD. Compounded non-FDA-approved menopausal hormone therapy prescriptions have increased: results of a pharmacy survey. Menopause. 2016;23:359-67.
  6. Stuenkel CA, Manson JE. Compounded bioidentical hormone therapy: Does the regulatory double standard harm women? JAMA Internal Medicine. 2017;177:1719-20.
  7. Santoro N, Braunstein GD, Butts CL, Martin KA, McDermott M, Pinkerton JV. Compounded bioidentical hormones in endocrinology practice: An endocrine society scientific statement. J Clin Endocrinol Metab. 2016;101:1318-43.