title: A review on the relationship between gluten and schizophrenia: Is gluten the cause?
abstract: BACKGROUND
  Schizophrenia is a chronic disease that possesses various clinical manifestations. It presents rather heterogeneous characteristics with respect to onset type, symptoms, and the course of the disease. Although the lifetime prevalence is as low as 1%, it can cause serious disability. Thus, it is very important to develop efficient treatment methods. In some studies, it is hypothesized that removing gluten from the diet leads to a significant improvement in disease symptoms. Epidemiological studies revealed that the prevalence of celiac disease among schizophrenic patients is almost two times higher than that of the general population.
  
  
  OBJECTIVE
  In this review, we evaluate the effects of gluten and celiac disease on the onset of schizophrenia. Efficacy of gluten-free diet applications, antibody response against gluten, and the interaction of the brain-gut axis and the presence of common genetic points are also investigated.
  
  
  METHODS
  Without any publication date restriction, Pubmed database searches were made for 'schizophrenia, gluten, gliadin, celiac disease, exorphin, brain-gut axis, psychiatric disorders.' The keywords and the articles about the schizophrenia-celiac disease relationship are included in our review.
  
  
  RESULTS
  Several studies presented evidence to suggest that symptoms associated with schizophrenia were minimized when gluten was excluded from patients' diets. Immunological searches revealed that most schizophrenic patients with increased anti-gliadin antibodies did not possess celiac disease; yet, the presence of increased antibodies against gliadin can be the share point of the immunological abnormalities found in both of the diseases.
  
  
  CONCLUSIONS
  There were no consistent results in the clinical, immunological, microbiological, and epidemiological studies that investigated the relationship between schizophrenia and celiac disease. This presents a need for a larger scale study to confirm the presence of this suggested correlation between schizophrenia and celiac disease. The underlying mechanisms between the two diseases should be explored.
authors.affiliation: a Faculty of Health Sciences, Department of Nutrition and Dietetics , Bahçeşehir University , Beşiktaş, Istanbul , Turkey.
authors.forename: Can
authors.initials: C
authors.lastname: Ergün
authors.affiliation: b Manisa Mental Health and Diseases Hospital , Şehitler Street, 45020 Manisa , Turkey.
authors.forename: Murat
authors.initials: M
authors.lastname: Urhan
authors.affiliation: b Manisa Mental Health and Diseases Hospital , Şehitler Street, 45020 Manisa , Turkey.
authors.forename: Ahmet
authors.initials: A
authors.lastname: Ayer
mesh_terms: D002446:Celiac Disease / Q000453:epidemiology* / Q000209:etiology; D055050:Diet, Gluten-Free; D005983:Glutens / Q000009:adverse effects*; D006801:Humans; D015201:Meta-Analysis as Topic; D015995:Prevalence; D016032:Randomized Controlled Trials as Topic; D012559:Schizophrenia / Q000453:epidemiology* / Q000209:etiology
chemical_list: D005983:Glutens
keywords: Celiac disease; Exorphin; Gliadin; Gluten; Schizophrenia