The things that I wonder about helping cause my MAC are: Spa pool use, Hormones/perimenopause, anxiety/stress, vegetarian(was eating very little protein), allergy sufferer all my life and sinus problems, family history of lung issues. Lets see what we have in common, if we all list what we think may have helped MAC get a hold in us , and reply to each others comments with what we have in common we may come up with interesting info.