There is such conflicting info about soy and estrogen levels. Some studies say yes and some say no. Soy contains isoflavones which contain plant estrogen. However, some studies have shown that plant estrogen behaves differently than animal estrogen so it doesn't affect the body in the same way.
I used to be a big drinker of soy milk because regular milk upsets my stomach. However, since starting on my workout and diet regimen, I haven't had any but mostly for the calories than anything else but I have to wonder. And I'm female! LOL.
Probably be safe to eat a little tofu but I wouldn't go crazy. There are plenty of other lean proteins out there to choose from. Can I ask why tofu and not lean meat?