Because steroids are lipophilic, they diffuse easily through the cell membranes, and therefore have a very large distribution volume. In their target tissues, steroids are concentrated by an uptake mechanism which relies on their binding to intracellular proteins (or " receptors ", see below). High concentration of steroids are also found in adipose tissue, although this is not a target for hormone action. In the human male, adipose tissue contains aromatase activity, and seems to be the main source of androgen-derived estrogens found in the circulation. But most of the peripheral metabolism occurs in the liver and to some extent in the kidneys, which are the major sites of hormone inactivation and elimination, or catabolism (see below).
All bets are off the table when high-dose testosterone and its many metabolites are used illegally, such as with anabolic steroid abuse. Strokes, embolisms, and cardiovascular disease are all more likely, as is sudden death, and liver and kidney disease. 44 In women, acne, irreversible deepening of the voice, baldness, increased facial hair, enlarged sex organs, breast reduction, depression, and infertility have all been reported. In adult men that abuse anabolic steroids, acne, baldness, permanent infertility, gynecomastia, loss of libido, erectile dysfunction, testicle shrinkage, and profuse sweating are all reported side effects. Increased testicular cancer hasn't been reported, though. 45,46