The question you ask has been hotly debated for awhile now. Some will say that it increases natural test while decreasing estrogen. Some say that it only decreases estrogen, while others say it does nothing. The truth of the matter is that everyone is different and may have a different reaction to 6oxo. Therefore, I would have to suggest you give it a try and see how it works for you. I used it after some prohormone usage along with ZMA and felt it worked okay for me. Nothing special, and probably only a little difference.