Testosterone is from the androgen class of steroid hormones and it is made from cholesterol by Leydig cells in the testicles. The brain detects we don’t have enough testosterone in our blood for our body’s needs and so it commands the pituitary gland to make more. The pituitary gland sends signals to the Leydig cells to get on with converting the cholesterol pregnenoloneLancet in our blood into a variety of hormones typically starting with Pregnenolone which is subsequently broken down and further processed into progesterone which goes through further processing to become Androstenedione and finally in the last stages of production it becomes testosterone. The alternative route for our tests to produce testosterone is after the Pregnenolone stage that it is converted into DHEA and later into Androstenediol before final conversion into testosterone.
Indeed after the testosterone has served its purpose of driving our sexual interest and growing us more muscle mass, the testosterone breaks down too into further hormones in particular estrogen – the female hormone. Our hormone levels are always being produced and changed into other hormones and the issues of our diet and exercise levels are major contributing factors. Higher protein and fat diets lend themselves to higher production levels which is why body-builders never expect to lose fat and weight when they commence heavy training schedules.
In no small measure our free testosterone level is always in a contest with our estrogen levels and our estrogen levels are a bi-product of testosterone that has been spent and used up doing its manly things for us. Many body builders who use synthetic testosterone also ingest estrogen blockers so that the balance of hormones is always in favor of the testosterone. The real issue is that we have constantly changing levels of hormones in our body and that they are always being broken down by metabolism into other compounds and hormones before being filter out of our body by the kidneys and liver.