Soy causes hormone imbalances. It's also a known toxin. Traditional societies that eat soy only eat it in fermented form. The soy industry has successfully campaigned to persuade people that soy is healthy and almost a miracle food. It is definitely not. It is causing little girls to menstruate as young as 8 and even younger. It can cause ovarian cysts and breast cancer.
When you read sites on the wonders of soy, find out who is funding them and where there information comes from.
The site below is non-profit and purely aimed at educating people. Do your body a favour and give up soy (unless it's miso, natto, soy sauce, tempeh and other traditional foods!).