Testosterone is not just a sex hormone. It should be seen as a total body hormone, affecting every cell in the body. The changes seen in aging, such as the loss of lean body mass, the decline in energy, strength, and stamina, unexplained depression, and decrease in sexual sensation and performance, are all directly related to testosterone deficiency. Degenerative diseases such as heart disease, stroke, diabetes, arthritis, osteoporosis, and hypertension are all directly or indirectly linked to testosterone decline. Secondly, testosterone also functions as a pro-hormone. Local tissue conversion to estrogens, DHT, or other active metabolites plays an important part in cellular physiology."
