http://www.mayo.edu/comm/mcr/news_773.html http://drcranton.com/CFIDS.htm The Mayo Clinic has proven just recently that fungus can and will cause strange, atypical "immune type" reactions in almost all people who suffer from chronic sinusitis. I really think that this can easily extrapolate over to other parts of the body as well such as the intestines and IBS-symptoms.I also think that certain extremely vulnerable people can be hit so hard that CFIDS is the end result. However, I am sure that CFIDS is more complicated than just yeast hypersensitivity, but this could be a good place to start the unwinding of all the dysfunction that is going on.