Soy, especially "refined" products like Tofu are bad for human males.
They promote the strong generation of estrogens, severely lower
testosterone, and basically cause sperm to self destruct.
Sounds like urban myths right? Well, I checked MedLine and there are
several rather conclusive extracts which demonstrate a HUGELY strong
correlation. How strong is HUGELY strong? If you drop a few objects
after hearing people mention that gravity theory, you can get a good
grip on gravity being a factor in the "falling"... this is about the
same level as that gravity thing.
Look at the Nagata C, Takatsuka N, Shimizu H, Hayashi H, Akamatsu T,
Murase K study (if ya couldn't tell, they're all Japanese names, and
it's a Japanese study, published in English), or the recent stufy by
Professor Lynn Fraser of King's College London (in England, if there
was any mystery).
Soy is the equivilant of taking weak birth-control pills all month long
(remember birth-control pills are 20+ placebos and maybe 2-7 actual
strong estrogen pills). As such, it's not suggested.
A LOT of people are reading saying "That certainly explains a LOT about
Japanese (or other oriental) men"... And theories now abound about
height, facial-hair and other secondary sex-characteristics, behaviour,
etc...