<<Disclaimer: Verify this information before applying it to your situation.>> Hi All, I have tried, unsuccessfully, to find the reference, but I am sure it is in _Not All In The Mind_ by Dr. Richard Mackarness. As I remember it, he states that cigarette smoke alters ph (reducing acidity) at the cellular level, in the digestive tract and in the lungs. Althoug this runs contrary to part of my own experience, as my stomach seemed more acid after a cigarette, the rest fits. I was dx'd 5 months after quitting smoking, and my cd symptoms were definitely worse during that period. I also used to cough up a little blood, from time-to-time, but nothing serious. I have had a couple of serious bouts of pulmonary bleeding, since going g-f. I now think that I may have breathed some flour dust both times. I breathed lots of flour before dx'd and had no such problem. Apparently the ph level has a lot to do with inflammation and permeability at the cellular level. I don't know about the biochemistry, but I do know that most of it fits with my experience. I hope that is helpful. Best Wishes, Ron Hoggan