Estrogen and Men….It’s a little complicated, but there is “a number”.
Men make testosterone, estrogen, and progesterone. Testosterone dominates the male hormonal landscape. Beginning around an average age of 42, men typically begin to experience a decline in testosterone production. Estrogen production, however, doesn’t drop much, and hence its blood and tissue levels, compared to testosterone, increase. This can lead to “estrogen dominance”.
Signs and symptoms of estrogen dominance include increased body fat, fatigue, mood swings, reduced libido, and gynecomastia. When men first seek hormonal and metabolic optimization, some degree of estrogen dominance is usually at play, and it’s tempting to treat this aggressively by simultaneously boosting testosterone and blocking estrogen. In fact, a common “formula” used by doctors beginning in bioidentical hormones is to combine a testosterone preparation with an estrogen blocker (anastrozole, known by its brand name Arimidex).
I used this formula myself when I first started. It made things very simple. However, as my knowledge base grew, I realized that this simplistic approach is flawed. You see, completely blocking a man’s estrogen robs him of the hormone’s benefits. Estrogen is critical to bone density as well as both cardiovascular and central nervous system health. When I explain BHRT to patients, I often refer to testosterone as the “vitality” hormone and estrogen as the “longevity” hormone, and while it’s true that ideal estrogen levels reduce body fat, improve libido, and support mood, mounting evidence suggests that where it really shines is in the prevention of age-related diseases and disorders.
I still prescribe anastrozole when it is needed to dial in the ideal estrogen level within the context of a testosterone/estrogen ratio. Over the years, based upon my clinical experience and my continuous review of the literature, I’ve concluded that the ideal estrogen level for most of my male patients is 40 nanograms per deciliter.
Why 40 ng?
Clinical experience over the past 11 plus years has taught me that most men simply feel good and look good with estrogen levels around 40ng/dl. The latest research suggests that levels lower than 40 ng/dl likely won’t offer the cardio and neuroprotective benefits that estrogen might provide. Hence, 40ng/dl is my target.
So long as testosterone levels are well-supported, estrogen levels 40ng/dl practically guarantee that men will not develop true gynecomastia, which involves growth of normally quiescent breast gland tissue. Overly fat men might still develop “man boobs” consisting of increased numbers or size of adipocytes, but this is different pathology and is best treated by diet and exercise.
In my next blog, I’ll share my thoughts about the testosterone “sweet spot” that works for most men.