The copper hypothesis of schizophrenia: a review

The hypothesis that excess tissue copper can cause schizophrenia is a relatively old theory that has never been compellingly demonstrated nor convincingly refuted. This article traces the development and abandonment of the copper hypothesis and examines the evidence for and against the etiological involvement of copper in schizophrenia. A plausible mechanism by which copper excesses could result in schizophrenia is presented and evaluated, and various attempts to reconcile the contradictory data are considered.