Hi Suze, Thanks so much for your post!  I could have written it myself.  I have had gastric issues, heartburn, etc. accompanied by numbness and tingling in my hands, feet (now moving to arms and face...ugh!), fatigue and some muscle cramping/twitching/pain.  My gastroenterologist told me that they weren't related, and focused on the endoscopy results....typical GERD, espophagus, gastric sensitivity issues.  I thought I had celiac disease, since I have bad tingling a day after after bowel upset, but that biopsy test was negative.  I have tested low for Vitamin D, but not too low (32).  Now I'm concerned that maybe I have MS, since the Vitamin D supplement my doctor told me to take isn't helping...she said take Citrical w/D, which is only 1,000 iu.  I feel like it's not even being absorbed with all my digestive issues!  She's checking my levels again and sending me to a neurologist.  I just want a firm diagnosis and acknowledgment that the GI issues and the tingling issues are totally related.  Thanks so much for your post...it totally justifies what I've been experiencing all along!