Schizophrenia and coeliac disease

166 randomly selected patients with well documented chronic schizophrenia were screened for evidence of folate deficiency. A low serum folate, low red cell folate or both was found in 14 of these patients. Small intestinal biopsies were obtained in 12 of these patients, and in one nonschizophrenic psychiatric patient with a low serum and red cell folate. The biopsies showed no histological or biochemical abnormality. The phenylalanine of all 166 schizophrenic patients, the nonschizophrenic patients and the controls were normal. This study shows that at a hospital in the West of Ireland there is no evidence that coeliac disease makes any significant contribution to the high admissions with a diagnosis of schizophrenia. On the other hand a significant number of the patients had a low blood folate, perhaps because they were not eating the food provided, and they might benefit from supplementary vitamins including folic acid.