but might they decrease male fertility?

Fox News thinks so - and they're fair and balanced...

Fact or fiction? Fiction, and it's interesting why.

The study did find that soy decreased sperm concentration

but did not significantly affect the sperm count itself.

How can you have the same number of sperm but a lower concentration?

Because of a larger ejaculate volume.

Soy appears to stimulate the prostate gland to produce a larger load of ejaculate fluid,

but the actual number of sperm remains the same.