International variations in the outcome of schizophrenia and the prevalence of depression in relation to national dietary practices: An ecological analysis

In this 2004 study, Peet sought to establish dietary factors that can predict the outcome of schizophrenia as well as the prevalence of depression. Variations in diet had already been known to predict the incidence of diabetes and heart disease, but its influence on mental health had not been evaluated yet. Peet performed an ecological analysis (a method of investigating the effects of time-specific interventions on population health at a large scale). National dietary patterns were analyzed against international variations in the outcome of schizophrenia and prevalence of depression. The results showed that a higher national consumption of refined sugar and dairy products predict a worse 2-year outcome of schizophrenia. Moreover, low dietary intake of fish and seafood could predict a high national incidence of depression. Therefore, Peet concluded that the dietary factors that predict schizophrenia outcome and occurrence of depression are similar to the predictors of coronary heart disease and diabetes, in which nutritional approaches are recommended. [NPID: depression, psychiatric disorders, schizophrenia, fish, seafood, refined sugar, dairy products]

Year: 2004

Reference: Peet M. (2004). International variations in the outcome of schizophrenia and the prevalence of depression in relation to national dietary practices: an ecological analysis. The British journal of psychiatry : the journal of mental science, 184, 404–408. https://doi.org/10.1192/bjp.184.5.404