Testosterone is a hormone important for sexual and reproductive development and belongs to a group of male hormones called androgens, which are sometimes called steroids or anabolic steroids. In men, testosterone is produced mainly in the balls (testes) with a small amount made in the adrenal glands.
The brain's hypothalamus (almond size) and pituitary gland (pea size) control testosterone production. Through chemicals and hormones in the bloodstream, the hypothalamus tells the pituitary gland how much testosterone to produce, and the pituitary gland passes the message on to our balls.
For much of our lives we produce minute quantities of this little miracle-worker which is vital to our bone density, muscle strength and mass, fat distribution, facial and body hair, red blood cell production, sex drive and sperm production.
Testosterone levels generally peak during adolescence and early adulthood after which your testosterone level gradually drops off, around 1% a year from your 30s-40s. This is usual but should not be confused with hypogonadism, a disease in which we are unable to produce normal amounts of testosterone. Testosterone replacement therapy can improve the signs and symptoms of low testosterone and you should see you GP if you have concerns.
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