Diagnosing hypogonadism is a process that should involve blood work and a review of symptoms. Even if your total serum testosterone is above the clinical normal range you can still be experiencing castrating effects. Questioneers such as ADAM should be applied to the review.

There are two main categories of hypogonadism: primary, which indicates something wrong with your testicles, and secondary, which basically means that the problem is located in the hypothalamus-pituitary axis in the brain.

As men age, we see a steady decline in the whole production chain. Your whole system is basically slowly degrading, making your body produce less testosterone, and making your cells less responsive to its influence. As testosterone decreases, SHBG rises and along with it so does estrogen due to increased aromatase. The negative feedback loop also becomes more sensitive to estrogen as we age.

Total serum testosterone is most often used to measure the testosterone output, but because the castration effect can happen due to faults in several other places than the direct output of testosterone, it is not always going to give the correct picture of what is going on.

On a cellular level, your body’s androgen receptors may be malfunctioning making them insensitive to testosterone. This can be due to something called CAG repeats within the receptors due to genetics.