A leading misconception in the world of health optimization is that testosterone is a “men’s” hormone and estrogen is a “women’s” hormone. This couldn’t be farther from the truth. Testosterone and estrogen play essential physiological roles in both men and women. Often overlooked is the function of testosterone in women, and estrogen in men. Optimal physiology stems from harmonious hormonal balance, not from one hormone's dominance over another. 

One of the primary presuppositions driving this myth is the false notion that estrogen is the “opposite” of testosterone. Estrogen is a direct metabolite of testosterone. Estrogen is synthesized through two pathways; the first being from testosterone directly via the enzyme aromatase, and alternatively from Estrone (E1) via 17 beta-hydroxysteroid dehydrogenase. Understanding the aromatase pathway sheds light on the importance of optimal T:E balance. 

Estrogen in Men 

While testosterone certainly deserves its spotlight in male sexual health, estrogen (as estradiol or E2) plays a significant role in sexual function. Adequate E2 is required for libido, erectile function, and spermatogenesis in men. The spongy tissue responsible for erections, known as the corpus cavernosum, is dense with estrogen receptors. Estradiol works in conjunction with testosterone to regulate libido. When it comes to hormonal health, consider that more is not always better… balance is key. Both excessive and insufficient estrogen levels can result in low libido, poor erectile quality, and mood disorders. (1)

“In both rats and humans, ERα, ERβ and aromatase were profusely expressed in male brain, and masculinization of male brain is modulated by locally produced estrogen. Estrogen can influence mood, mental state, cognition, and emotion through an interaction with serotonin receptors. In men with aromatase deficiency, estrogen treatment enhances libido, and sexual activity”.(2) 

Beyond the bedroom, estrogen plays an important role in ensuring optimal bone mineral density in men, potentially more so than testosterone according to one study (3). Estradiol, in balanced concentrations, confers cardiovascular benefit mediated through the effect of the estrogen receptor on endothelial activity, oxidative stress, and fibrosis. Estrogenic pathways may also promote muscle growth as the estrogen receptor beta (ERβ) shows potential as a novel target for the treatment of bone and muscle wasting conditions. (4)

Testosterone in Women

Testosterone is essential for women, in part due to it being one of primary drivers of estrogen synthesis. Estradiol can be formed through aromatization of testosterone, or reversibly converted from estrone directly within the ovaries. Without sufficient testosterone levels, women are likely to suffer the deleterious impact of low estradiol. But testosterone itself exerts its own independent roles in female physiology. (5)

Sufficient testosterone levels are strongly associated with mood and the will to effort, and for good reason. One study concluded that T levels directly alter the brain structures responsible for dopamine synthesis in the brain, highlighting the importance of balanced sex hormones for optimal brain function. Testosterone directly supports sexual health, with low T levels having been linked to loss of sexual desire, vaginal dryness, and inability to achieve orgasm. (6,7)

Testosterone plays critical functions as a maintainer of skeletal muscle and bone mineral density. The prevalence of sarcopenia (muscle loss) and osteoporosis (bone loss) after menopause is largely the result of sex hormone decline. Androgens in women are essential for body composition, insulin sensitivity, and lipid management, all key vectors for longevity. (8)

This is not to say that men need to supplement with estradiol, or women need to start taking TRT. However, debunking the myth that “Testosterone is a men's hormone” and “estrogen is a women's hormone”, is essential if our goal is total health optimization. Hormone optimization is a delicate task. Working with a medical team that understands the intricate nuance of hormone cascades leads to substantially better results. Our team at Marek Health offers just that. To learn more about how holistic medical oversight can help you conquer your goals, (CTA)

Disclaimer: This blog post/article is for informational purposes only and does not constitute medical advice. This is not a substitute for professional medical advice and should not be relied upon. If you are considering a treatment, always consult your primary care physician to discuss the risks and benefits.

1. The role of estradiol in male reproductive function

2. Different levels of estradiol are correlated with sexual dysfunction in adult men

3. Estrogens and bone health in men

4. Selective estrogen receptor-β activation stimulates skeletal muscle growth and regeneration

5. Testosterone in women--the clinical significance 

6. Physiological Effects of Androgens in Women 

7. Testosterone Induces Molecular Changes in Dopamine Signaling Pathway Molecules in the Adolescent Male Rat Nigrostriatal Pathway

8. The association between serum testosterone and insulin resistance: a longitudinal study