INS and hypogonadism: In conclusion, comparing the metabolisms recorded in cases of IS and IR hypogonadism before testosterone restoration, we can affirm that, independently of the presence or absence of insulin, testosterone deficiency results in lactate decrease, acetyl-CoA decrease, TCA cycle reduction, blockage of the production of acetyl-carnitine (and consequently blockage of the β-oxidation of fatty acids) and blockage of collagen synthesis and carnosine production.