A decrease in hospital admissions for schizophrenia in countries that had limited bread consumption during World War II, which suggested a possible relationship between bread and schizophrenia.
Dohan and colleagues also observed that overt schizophrenia was rare in remote tribal areas of several South Pacific islands where grains were rare, as compared to similar populations which had a higher prevalence of overt schizophrenia and grain consumption
There have been several small controlled studies in which a gluten-free diet showed promise in ameliorating schizophrenic symptoms. In one such study, approximately 10% of schizophrenic patients had improvement in their symptoms by elimination of dietary gluten
This study was motivated by the observation that patients with schizophrenia tended to eat more carbohydrates immediately before a psychotic episode.
Additionally, low-carbohydrate, ketogenic diets have a long history for the treatment of refractory pediatric epilepsy and recently have been studied as a treatment for obesity and cardiometabolic risk reduction
There is no data to suggest that altering the fiber content of a diet will change the symptoms of patients with schizophrenia.
While more research is needed to confirm the association between gluten intake and schizophrenia and whether dietary change can ameliorate schizophrenic symptoms, health care providers could consider screening patients with schizophrenia for celiac disease and/or augment the medical regimen with a gluten-free or low-carbohydrate, ketogenic diet.