I think it is also very important to look at who the study was done on.
I mean for a simple compairasin lets take milk now I know most people here do not drink it but stay with me a moment.
Milk contains a sugar called lactose basic stuff we all know this.
We also know that most adults lose the ability to digest this sugar with or without symptoms like gas, bloating, stool problems which are the indicator for most people to say "I'm lactose intolerant" the number of lactose intolerant people is much higher.
Why you might ask?
Well American Indians,Asian,Afrian, decendants are mostly lactose intolerant but people of European ancerstery often are not.
It was an evolutionary thing, were milk was a mainstay of survial adults retained the ability to digest milk properly.
Whats this got to do with soy?
Well in studies of Asian women soy shows almost nothing but good results.
But take a woman like me who is of Italian,American Indian, scottish and African American heratige, soy messes me up something bad in fact cuting it out of my diet compleatly was the only way to stop some of the unbearable pain of endo, now before you say I'm mental untra sound also showed a significant improvment.
My doctor says it is the first thing he advises women with Endo to discontinue soy from thier diet because it almost always shows an improvment once soy is gone.
Point is you can do all the studies you want on food but unless you do an extreamly in depth study seperating people little by little you can not be sure on what the risks/health perks are.