I recently watched a BBC documentary ion this, a guy with Crohns who said he had crusting lips problems and limited diet infected himself with Hookworm and said his lips were fine and he could now eat whatever, disturbing as it sounds. They said the ideal is for drugs to replicate these effects without the organism, but this takes time and trials etc. I have also thought we probably mostly already have all kinds of things (Its inevitable it's the law now you have to pick up your dogs crap!) and whether this could be related as a cause even.