Confirmatory Efficacy Trial of a Gluten-Free Diet in a Subgroup of Persons With Schizophrenia Who Have High Levels of IgG Anti-Gliadin Antibodies (AGA IG)

This study is a randomized double blind clinical trial being funded by NIMH. Investigators will need to enroll 40 cases with AGA IgG positivity in order to present a powered and convincing result about the efficacy of gluten withdrawal in the subpopulation of persons with schizophrenia with elevated AGA IgG levels. Investigators will recruit a minimum 50 to ensure they are well powered without question, and to account for dropouts. Investigators will use a battery of measures of peripheral and central inflammation as well as gut permeability at baseline and endpoint to confirm the relationship of these outcomes to changes in AGA IgG and symptom changes in the clinical trial. Investigators will test negative symptoms as a primary outcome but will test changes in other symptom domains such as positive symptoms. After the completion of the 5 week confirmatory study, investigators will discharge participants and follow them for 8 weeks in their own environment to test the maintenance of the effect following the stringent GFD, and provide education on gluten free shopping, cooking and eating.