Fish oils may help fight off psychotic episodes, new research has suggested.
Patients given supplements containing omega-3 fatty acid were 27.5% less likely to progress to a state of serious psychosis than those who were not.
Scientists believe the explanation may lie in the way omega-3 may affect the structure of cell membranes in the brain and improve connections between nerve cells.
The study used 81 people at a very high risk of psychotic disorders characterised by delusions and hallucinations.
This included individuals who either have mild psychotic symptoms, were suffering from a short-lived "transient" episode of psychosis, or have a family history of psychotic disorders. Up to 40% of people in this category will become fully psychotic over the course of a year.
Omega-3 capsules also appeared to reduced psychotic symptoms significantly and improve mental functioning compared with the placebo.
The scientists, led by Paul Amminger, from the Medical University of Vienna, wrote in the journal Archives of General Psychiatry: "The finding that treatment with a natural substance may prevent or at least delay the onset of psychotic disorder gives hope that there may be alternatives to antipsychotics for the prodromal (early symptomatic) phase."