There are constant debates and many studies arguing the potential side effects for a user. There are studies showing that GW-501516 has caused cancer in rats while other studies refute it. The ONE study that was conducted that showed this issue was deeply flawed and refuted time and time again. GW-501516 dosing was not only abused but ran at insurmountable amounts of time within this study. When ran properly, it has actually been used as a cancer treatment. There are no known side effects associated with GW use and the only need to cycle off is so that one’s body does not acclimate or desensitize to use. There is no suppression, no toxicity and no other common side effects. This makes GW even more desirable amongst the bodybuilding community.