It is quite perplexing. A year ago, we were consuming a whole lot of gluten in my household. Loads of pasta and bread and everyone was doing just fine. Within a matter of weeks, my wife was up literally almost all night, every night with "gastro issues." She lost an unhealthy amount of weight, and she also began developing these dry, patchy skin irritations. One was on the side of her head and made her hair fall out. She was (not shockingly) developing depressive and anxious symptoms. She must have seen 9 or 10 different doctors, was in therapy, and was finally diagnosed with Celiac. We immediately cut all gluten from our diet, and eventually had to cut out dairy as well for some reason.
I never would say anything to her, but I was skeptical about the whole thing because she was seeing a couple homeopathic doctors. Within a couple weeks of the dietary changes, however, her health started to improve significantly and her hair grew right back. Weird stuff.