Variation, I cannot remember all of the research I did nor all of the specific reasons why, but I remember reading the research and it was clear that soy was bad. That's how I am about research. I read, read, read some more, make the conclusion and remember that. I only go back if new info is found on something. I'm not going to retrace my steps just to try to prove to you something.
Believe it or not, do your own research or not, but soy is, and this is obviously my opinion, poison. I find it very sad that soy is touted as a healthy substitute for anything. And I'm the guy who thinks dnp isn't all that bad, lol.