Over the past several years, the media has bombarded us with various treatments for low serum testosterone in men to prevent andropause, the male equivalent of menopause in women. But a study published in the Asian Journal of Andrology pointed out that estrogen “also plays a critical role in male sexual function.”
Surprisingly, research shows that it may not be just a testosterone deficiency that leads to reduced sexual desire and potency as men age but also a deficiency in estrogen—the “female hormone.” The study points out that estrogen is needed by men as well as women and offers clear evidence that too little estrogen can cause certain male menopause symptoms. Testosterone is the main male sex hormone, and in men, some of the testosterone is converted into estrogen. As men age, the levels of both testosterone and estrogen diminish.
When men report to their doctors that they are experiencing the symptoms of andropause—diminished libido, fertility, and energy—most physicians prescribe a testosterone patch, cream, or injection. (Testosterone cannot be given by mouth because it is very toxic to the liver when taken orally.) Physicians do not usually prescribe estrogen for men, and the study indicated that the way to remedy low estrogen is to give men testosterone and allow the body to convert it.
The study reviewed research in which men with low testosterone levels were given drugs that prevent the conversion of testosterone into estrogen. This allowed researchers to compare the effects of different levels of both estrogen and testosterone on libido, erectile function, and sperm production.
The researchers concluded that though excess estrogen increased erectile dysfunction, both testosterone and estrogen were needed to maintain normal sex drive and optimal sperm production.
Animal research supports this observation. In one experiment, mice that were altered so they did not produce any estrogen had no sex drive. And on the human level, male-to-female transsexuals were noted to have an increased libido when given estrogen.
Current research seems to support the need for testosterone replacement as men manifest signs of andropause. Unlike estrogen, however, testosterone does not fall off as sharply with age as estrogen does in women after menopause.
Ultimately, if a man’s serum testosterone is below the normal level and he experiences the symptoms of andropause, it seems medically safe, prudent, and efficacious to prescribe testosterone replacement therapy in a monitored environment. As the population ages and life expectancy increases, the case for prescribing testosterone—to prevent frailty, increase muscle and bone strength, enhance mobility, and improve impaired thinking skills—becomes more justifiable, and its use can be expected to increase dramatically in the years to come.