Testosterone Suppression – When we supplement with anabolic steroids our natural testosterone production is suppressed. This applies to Winstrol just as it does any steroid. For this reason, most men will need to supplement with testosterone when they supplement with Stanozolol. The form does not matter as long as you’re providing the body what it needs. As testosterone production is suppressed testicular atrophy will occur. However, once use is discontinued and all anabolic steroids have cleared your system testosterone production will begin again, and your testicles will return to their normal size.
To strengthen the anabolic properties of testosterone, more than 100 synthetic steroid derivatives have been described for human purposes. The anabolic effect promotes protein synthesis, muscle growth and erythropoiesis. In clinical practice, substances with anabolic effect are needed to overcome various catabolic states. However, none of these compounds are devoid of androgenicity. Androgenic and anabolic properties of anabolic steroids cannot be totally separated. Therefore, it is more appropriate to use the term anabolic androgenic steroids (AAS).
Winstrol in particular is known for exhibiting some profound negative cholesterol changes in humans as evidenced by some clinical studies. Winstrol administered orally at just 6mg daily for a 6 week period resulted in a reduction of HDL by 33%, alongside an LDL increase of 29% (all test subjects were healthy males engaged in regular physical exercise)  . Even the injectable Winstrol preparation has demonstrated to produce negative cholesterol profile changes. Only a single 50mg dose of injectable Winstrol was administered to 12 healthy test subjects, and resulted in significant HDL reduction with an increase in LDL (these negative cholesterol changes remained for a 4 week period following administration before returning to normal values)  .