This study asked … How many people who complain of gluten insensitivity are really sensitive to gluten? Not many, they found:

Non-Celiac Gluten Sensitivity Aong Patients Perceiving Gluten-Related Symptoms, Digestion, 30 May 2015

CONCLUSION: Eighty six percent of patients reporting gluten-related symptoms have neither non-celiac gluten sensitivity (NCGS), nor celic disease, nor wheat allergy. Self-perceived gluten-related symptoms are rarely indicative of the presence of NCGS.

86% of people who thought they were sensitive to gluten, weren’t. That’s something. If it’s not gluten, what is it?