New studies have however raised questions over whether the ingredients in
soy might increase the risk of
breast cancer in some women, affect brain function in men
and lead to hidden developmental ab-normalities in infants.
The core of their concerns rests with the chemical makeup of soy: in addition to all the nutrients and protein, soy contains a natural chemical that mimics estrogen, the female hormone. Some studies in animals show that this chemical can alter sexual development.