I believe it really depends on the user and their sensitivity to test or other androgens. I for ex: get puffy nips and little lumps after about 4 weeks on 500mg test while some fools can take a gram and up and have no problems. So know your limitations and weather you will need it or not, but its always good to plan ahead and have it incase gyno reers its ugly head, I have a friend who has juiced for 15yrs and never had problems until recently so dont think you are invencible.