A half serving of soy a day reduces sperm counts, even causing infertility. Now, I'll admit I don't mind tofu when it's prepared right, but a nice tri-tip steak will always kick soy's ass when it comes to my protien cravings. It seems that soy is girly to begin with -- it has estrogen-increasing properties -- so this gives guys a perfect way to deal with their hot vegetarian girlfriends: "Honey, you know what soy does to my little troopers..." Let the gals get the estrogen boost, and you order a California burger; your sperm will love you for it.