While soy itself isn’t a xenoestrogen, it contains isoflavones (such as daidzein, genistein, ODMA and equol) and lignans (such as enterodiol and enterolactone) that have estrogenic properties. Considering how much exposure we have to estrogenics overall, I don’t see a need to add isoflavones and lignans to the list by consuming soy and its byproducts.