Elaine writes:
With knowledge that generalizations are oversimplification, I will try and give you my gut reaction after digesting the input over 45 years - and if that sentence doesn't describe my one tract mind, nothing does. Yes, generally speaking, classical Crohn's, because it responds so miraculously to SCD, seems to be caused by more than normal numbers of
intestinal bacteria and yeast (microorganisms). The Malthusian population theory comes to mind: more food, more organisms. This is caused, in my opinion, by the dietary overload of starch which has created an overload on digestive enzymes so much of the starch just goes down to the fermentation tank and causes it swell in size and contents of
microorganisms (yeast and bacteria riding piggy back on each other). With SCD, we cut back on their food and the Malthusian Population Theory works. Less bacteria, less fermentation, less byproducts of fermentation, etc. = QUANTITATIVE, generally speaking. This may occur in ulcerative colitis when pathological microorganisms emerge. Antibiotics can do this; change in pH in the colon can do this; the withdrawal of nicotine can do this, as nicotine appears to have an antibiotic effect on colonic bacteria, etc and as a result a pathological type of bacteria takes over (example would beharmless aerobic E. coli changing to pathological anaerobic E. coli which produce deleterious toxins) = QUALITATIVE.

Originally from the Long Island listserve.