I bet all the stuff designed to kill microbes from food to cleaning products, is also killing the b12 bacteria in our bodies in our bodies. Its probably killing the bacterias, aswell as altering the ecosystems in the body.
But I also wonder if thats the case... someone must have superstrains of beneficial bacteria in thier bodies now. Just like there are super strains of non-benificial bacterias from all the anti-biotics.
Aswell how does a person get the bacterias to propegate again... I would like to think that just eating a bunch of pro-biotics would work, but if the environment isnt ready for them.... they will just die. Its like putting fish in a lake with not enough oxygen, they would just die.