I just saw that this post was written in 2012! But for anyone else who is thinking of doing an Ironman, I'll leave my response up.
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I have Celiac Disease confirmed by symptom (not biopsy) and presence of Herpetiformis Dermatitis and DNA HLA DQ 2 and 8 positive for Celiac Disease genetic risk. I have raced multiple Half Ironman distance, Sprint...