I was sent this link to an interesting article about Schizophrenia and diet. ( Also covers depression and diet.)
© 2004 The Royal College of Psychiatrists
International variations in the outcome of schizophrenia and the prevalence of depression in relation to national dietary practices: an ecological analysis
Malcolm Peet, FRCPsych Swallownest Court Hospital, Aughton Road, Sheffield S26 4TH, UK.Declaration of interest M.P. has received research funding fromLaxdale Ltd, a company which is developing ethyleicosapentaenoicacid as a treatment for psychiatric and neurological disorders.
Background Dietary variations are known to predictthe prevalenceof physical illnesses such as diabetes and heart disease butthe possible influence of diet on mental health has been neglected.
Aims To explore dietary predictors of the outcome of schizophreniaand the prevalence of depression.
Method Ecological analysis of national dietary patterns in relationto international variations in outcome of schizophrenia andprevalence of depression.
Results A higher national dietary intake of refined sugar anddairy products predicted a worse 2-year outcome of schizophrenia.A high national prevalence of depression was predicted by alow dietary intake of fish and seafood…
Here is some of the further info
…Conclusions The dietary predictors of outcome of schizophreniaand prevalence of depression are similar to those that predictillnesses such as coronary heart disease and diabetes, whichare more common in people with mental health problems and inwhich nutritional approaches are widely recommended. Dietaryintervention studies are indicated in schizophrenia and depression.
The most consistent finding is that a greaterconsumption of refined sugar is associated with a worse outcomeof schizophrenia and a greater prevalence of depression. Inthe schizophrenia data-sets, a high correlation with sugarconsumption was seen both for outcome measures based on hospitaladmission and those based on social outcome. Other correlationsthat were found in both schizophrenia data-sets but not necessarilyfor both admission and social outcome measures included theconsumption of meat and eggs (adverse relationship) and theconsumption of pulses (beneficial relationship). Dairy productsand alcohol consumption were associated with a poor outcomein the IPSS study but not in the DOSMED database. With regardto depression, the strongest association was between a highdietary intake of fish and seafood and reduced prevalence ofdepression. A high intake of dairy products and sugar was associatedwith an increased prevalence of depression, whereas a highintake of starchy roots was associated with a reduced prevalenceof depression…
…Diet and outcome of schizophrenia
The finding that the outcome of schizophrenia is better in developingthan in developed countries has never been satisfactorily explainedand does not appear related simply to confounding factors suchas diagnostic differences and selective outcome measures (Hopper & Wanderling, 2000).Christensen & Christensen (1988)reported a correlation between international variations inoutcome of schizophrenia according to the IPSS study and theratio in the diet of animal (mainly saturated) fat to fish andvegetables (mainly polyunsaturated) fats. This was reflectedin the present study, where correlations were shown betweena higher consumption of meat and dairy products and a worseoutcome of schizophrenia. However, strong intercorrelationsare found between various dietary constituents, and on multipleregression analysis it was sugar consumption that was the predominantpredictor of poor outcome in schizophrenia. Exceptions to thiswere that the consumption of dairy products predicted hospitaladmission in the IPSS study, and alcohol was a weak predictorof global good outcome in the DOSMED study. Therefore, thedominant and robust finding of this analysis is the predictivevalue of sugar consumption.
Diet and prevalence of depression
There has been recent interest in the relationship between fishconsumption and depression. Hibbeln & Salem (1995) notedthat the increased prevalence of depression in the 20th centuryparallels the increased rates of coronary heart disease thatare thought to be associated with altered dietary patterns,including reduced dietary intake of omega-3 polyunsaturatedfatty acids. Hibbeln (1998) has subsequently demonstratedstriking correlations between dietary fish intake and internationalvariations in major depression. Using the same depression databaseas Hibbeln (1998), we have confirmed the relationship betweenfish consumption and international variations in rates of depression,and also found that sugar consumption relates to the prevalenceof depression. This had been noted previously by Westover &Marangell (2002). However, multiple regression analysis showsthat fish and seafood consumption provides the strongest andmost robust independent predictor of depression prevalence.