An obvious first question to ask when confronting the decision to start TRT—even before determining if your level is relatively low—is, Are there detrimental effects of a low testosterone level? This question has been definitively answered and it is standard practice to treat a low testosterone level—the disease state called ‘hypogonadism’—because the deleterious effects of long term untreated hypogonadism are well documented.
Hypogonadism affects many organ systems. It causes decreased lean muscle mass, strength, and bone density. When you see an older man who is stooped over and cannot hold his head up, this is most likely caused by osteoporosis directly resulting from low testosterone levels. In addition, a low testosterone level causes increased body fat, especially around the waist, both subcutaneous and visceral (clinging to the internal organs, such as the intestines and liver—the cause of the proverbial pot belly). This increase in abdominal fat starts a vicious cycle for its accumulation further suppresses testosterone production causing further accumulation of abdominal fat.
This increased visceral fat is not just an aesthetic concern. A growing body of evidence supports the theory that the accumulation of visceral fat causes a number of metabolic derangements which over time can greatly increase the risk of diabetes and cardiovascular disease.
Just as with estrogen, testosterone has equally potent effects above the neck as below. There are numerous receptors for testosterone in the brain. Not surprisingly, therefore, hypogonadism is associated with depression, a tendency toward social isolation, low libido, decreased spatial memory, and decreased sense of well-being and assertiveness.
Impotence is generally not caused primarily by hypogonadism. A more important cause of this is vascular and nerve damage; however, as stated above, low testosterone levels can increase vascular damage—including the vessels that are necessary for maintaining an erection. Through a direct effect, though, about five to ten percent of impotence is caused by a low testosterone level. This is not to say, however, that the decreased fullness of erection and the longer time necessary between ejaculations (called the ‘refractory period’) is not a result of waning testosterone levels with aging. Many men notice that these mild symptoms improve with TRT. Finally, a low testosterone level can also affect a man’s ability to maintain a normal red blood cell count.
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