Be careful when playing with soybean.

According to [1]:

"soy isoflavones have been found to inhibit CYP3A4 metabolism"

At least to me, the meaning of this is unclear: "inhibit CYP3A4 metabolism" could mean slowing the destruction of CYP3A4 itself, or it could mean slowing the speed of the the metabolism caused by CYP3A4. I've followed some of the papers cited in [1] and I think that the second meaning is correct. So, in that case soybean is a CYP3A4 inhibitor.

Similar to grapefruit juice, this has the advantage of increasing the AUC of levodopa, which is good. But, it can also lead to increasing the effect of other drugs (e.g. statins), which can result in an overdose.

Reference:

[1] "Interactions between CYP3A4 and Dietary Polyphenols
Loai Basheer and Zohar Kerem"
Oxid Med Cell Longev, 2015
Interactions between CYP3A4 and Dietary Polyphenols

John