not all gyno is from estrogen activity in the breast tissue.
something like 30% are of no known reasons, meaning Tamoxifen or the likes won`t help.
also, many times when you start to feel something wrong there, it`s already too late to do something about it.
Tamofixen might have a negative effect in the prostate.
i don`t know why but a lot of men seem to have a gyno, just a day ago i was watching a document about some african tribe and i could swear most of the men seamed to have it.
and they were skinny, not fat at all!
i doubt they were using steroids or had low levels of estrogen.
just a thought.