What is testosterone?

Testosterone is the most important male sex hormone. Testosterone has important functions throughout a man’s entire lifespan. In the unborn, it is responsible for the development of the male sex glands (testes) and the external male genitals. In puberty, the hormone is responsible for virilization (masculinization).

Furthermore, in the adult male, testosterone affects muscle mass as well as the male build and appearance. Testosterone also plays a major role in male health and well-being and has an impact on mood and energy levels. It is responsible for maintaining male sexual desire, sexual function and sperm production.