To create Dianabol, an additional 1-2 carbon bond was added to the testosterone molecule, resulting in a product that was up to 210% more anabolic (muscle building), and roughly half as androgenic (producing male sexual characteristics). The anabolic rating is very high, making it about twice as potent as testosterone, while the relatively low androgenic score means that it may produce far less side effects as an equal amount of testosterone. The 1-2 double bond is responsible for this difference, as it reduces the rate at which the drug can be converted to estrogen. Estrogen is typically responsible for many of the side effects athletes experience while using anabolic steroids-namely water retention and development of breast tissue. It would also appear that this bond prevents Dianabol from being much of a target for conversion to Dihydrotestosterone- which is also responsible for a host of side effects such as acne, hair loss, and prostate enlargement. Finally, Dianabol would also appear to be less suppressive of the body’s own hormonal system, and doesn’t cause the same harsh natural testosterone shut down that happens with injectable testosterone.