from my limited research, which can be wrong, i think you can get this from brocolli and another green veggie, but to get to the productive levels, you would need to eat like 9 lbs of brocolli.
i have a friend who uses this, and a couple other natural test boosters (tribulus and i think sustain), hes a nattie now, got off his TRT for a year now, since it wasnt working as well as he would've like. he was on test Cyp, then androgel, but with his new nattie booster cycle, DiM, sustain and tribulus, his free test and total test levels are higher now than before, than with the juice.
He was also saying, Dim keeps the free test from the boosters from turning back into estrogen while keeping estrogen levels in check? Maybe Needto or someone more educated can enlighten us on that.