The 4R Gut Rebuilding Program was first developed by the Institute of Functional Medicine, and this seems to be the best way to go about healing the gut. Unfortunately there is no good single source online that I can point you to, and everyone seems to have their own slightly different way of doing it, so I've come up with this summary of research about the program. (attached) A functional medicine doctor, naturopath or holistic doctor would be the kind of doctor to help you with this. You should interview them first to see if they do testing and what kind, and do all the steps, not just some of them. New version posted 9-11-2014 - fixed broken article link for the Liska / Lukaczer article reference.