We were talking about phytoestrogens, or plant-based versions of the hormone estrogen. Some breast-enhancement products contain phytoestrogens that actually cause the breast tissue to grow. Soy products such as soybeans and tofu are whole-food sources of phytoestrogens. Theoretically, therefore, eating tofu could cause your breast tissue to grow. However, you'd have to eat quite a bit of it, so the Wiley One suggested simply placing the tofu in your bra. Not only would you get the same effect, you'd also have a quick snack handy if you got hungry.