I think Yael had one in PMenu too recently.
Basically, your body is great at balancing itself out. If it needs to excrete more of this to keep blood pH balance then it will.
Blood pH is regulated to within about .1 IIRC so it's not like your body chemistry can deviate significantly. More or less it's all some sort of gimmicky thing. That said it's probably not healthy to eat the same thing all the time though.