Literature on the relationship between psychosis and nutrition
Arvindakshan, M., Ghate, M., Ranjekar, P. K., Evans, D. R., & Mahadik, S. P. (2003). Supplementation with a combination of ω-3 fatty acids and antioxidants (vitamins E and C) improves the outcome of schizophrenia. Schizophrenia research, 62(3), 195-204.
Reduced levels of membrane essential polyunsaturated fatty acids (EPUFAs), namely, arachidonic acid (AA), eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acids (DHAs), and their association with psychopathology have been consistently reported in both chronic-medicated schizophrenic patients as well as in never-medicated patients soon after the first episode of psychosis. Past supplementation studies with either omega-6 or omega-3 or both EPUFAs generally in chronic-medicated-older patients have reported varying degrees of therapeutic effects, and have suggested that supplementation with primarily omega-3 EPUFAs (EPA>DHA) may be preferable. We report the supplementation with a mixture of EPA/DHA (180:120 mg) and antioxidants (vitamin E/C, 400 IU:500 mg) orally morning and evening to schizophrenic patients (N=33) for 4 months. The red blood cell (RBC) membrane fatty acid levels, plasma lipid peroxides and clinical measures were carried out by established procedures at pretreatment, posttreatment and after 4 months of postsupplementation period to determine the stability of treatment effects within patients. Levels of fatty acids and lipid peroxides were compared with their levels in normal controls (NC) (N=45).Posttreatment levels of RBC EPUFAs were significantly higher than pretreatment levels as well as levels in normal controls without any significant increase in plasma peroxides. Concomitantly, there was significant reduction in psychopathology based on reduction in individual total scores for brief psychiatric rating scale (BPRS) and positive and negative syndrome scale (PANSS), general psychopathology-PANSS and increase in Henrich’s Quality of Life (QOL) Scale. The EPUFA levels returned to pretreatment levels after 4 months of supplementation washout. However, the clinical improvement was significantly retained. Future studies need be done in placebo-controlled trials and also with a comparison group supplemented with fatty acids alone in a larger number of patients, both chronic as well as never medicated, and for a longer duration of treatment while the dietary intake is monitored. This may establish the EPUFA supplementation a very effective treatment to improve the outcome for an extended period of time.
Gracious, B. L., Finucane, T. L., Friedman-Campbell, M., Messing, S., & Parkhurst, M. N. (2012). Vitamin D deficiency and psychotic features in mentally ill adolescents: a cross-sectional study. BMC psychiatry, 12(1), 38.
Background: Vitamin D deficiency is a re-emerging epidemic, especially in minority populations. Vitamin D is crucial not only for bone health but for proper brain development and functioning. Low levels of vitamin D are associated with depression, seasonal affective disorder, and schizophrenia in adults, but little is known about vitamin D and mental health in the pediatric population. Methods: One hundred four adolescents presenting for acute mental health treatment over a 16-month period were assessed for vitamin D status and the relationship of 25-OH vitamin D levels to severity of illness, defined by presence of psychotic features. Results: Vitamin D deficiency (25-OH D levels < 0.04). Race was no longer associated with psychosis when the results were adjusted for vitamin D level. Conclusions: Vitamin D deficiency and insufficiency are both highly prevalent in adolescents with severe mental illness. The preliminary associations between vitamin D deficiency and presence of psychotic features warrant further investigation as to whether vitamin D deficiency is a mediator of illness severity, result of illness severity, or both. Higher prevalence of vitamin D deficiency but no greater risk of psychosis in African Americans, if confirmed, may have special implications for health disparity and treatment outcome research.
Peet, M. (2003). Eicosapentaenoic acid in the treatment of schizophrenia and depression: rationale and preliminary double-blind clinical trial results. Prostaglandins, Leukotrienes and Essential Fatty Acids, 69(6), 477-485.
It has been hypothesised that polyunsaturated fatty acids (PUFA) play an important role in the aetiology of schizophrenia and depression. Evidence supporting this hypothesis for schizophrenia includes abnormal brain phospholipid turnover shown by 31P Magnetic Resonance Spectroscopy, increased levels of phospholipase A2, reduced niacin skin flush response, abnormal electroretinogram, and reduced cell membrane levels of n-3 and n-6 PUFA. In depression, there is strong epidemiological evidence that fish consumption reduces risk of becoming depressed and evidence that cell membrane levels of n-3 PUFA are reduced. Four out of five placebo-controlled double- blind trials of eicosapentaenoic acid (EPA) in the treatment of schizophrenia have given positive findings. In depression, two placebo-controlled trials have shown a strong therapeutic effect of ethyl-EPA added to existing medication. The mode of action of EPA is currently not known, but recent evidence suggests that arachidonic acid (AA) if of particular importance in schizophrenia and that clinical improvement in schizophrenic patients using EPA treatment correlates with changes in AA.
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, 184(5), 404-408.
Background: Dietary variations are known to predict the prevalence of physical illnesses such as diabetes and heart disease but the possible influence of diet on mental health has been neglected. Aims: To explore dietary predictors of the outcome of schizophrenia and the prevalence of depression. Method: Ecological analysis of national dietary patterns in relation to international variations in outcome of schizophrenia and prevalence of depression. Results: A higher national dietary intake of refined sugar and dairy products predicted a worse 2-year outcome of schizophrenia. A high national prevalence of depression was predicted by a low dietary intake of fish and seafood. Conclusions: The dietary predictors of outcome of schizophrenia and prevalence of depression are similar to those that predict illnesses such as coronary heart disease and diabetes, which are more common in people with mental health problems and in which nutritional approaches are widely recommended. Dietary intervention studies are indicated in schizophrenia and depression.
Van der Heijden, F. M. M. A., Fekkes, D., Tuinier, S., Sijben, A. E. S., Kahn, R. S., & Verhoeven, W. M. A. (2005). Amino acids in schizophrenia: evidence for lower tryptophan availability during treatment with atypical antipsychotics?. Journal of Neural Transmission, 112(4), 577-585.
Amino acids play a role in neurotransmitter availability in the central nervous system, in that e.g. the synthesis of brain serotonin depends on the concentration of its precursor tryptophan. Disturbances in amino acid metabolism have been implicated in the pathophysiology of schizophrenia.In the present study the effect of a 14 week treatment with atypical antipsychotics on the plasma levels of amino acids was investigated in patients with schizophrenia and compared to normal controls.Non-responders (< or =20% decrease in BPRS at endpoint) demonstrated lower baseline values of methionine as compared to good responders (> or =50% decrease in BPRS at endpoint; p<.05) and controls (p<.01). The ratio between tryptophan and the other large neutral amino acids (Trp/LNAA ratio) in poor-responders (<40%) decreased during treatment as compared to responders (> or =40%; p<.05). It is concluded that poor or non-response to atypical antipsychotics may be associated with an impaired synthesis of serotonin in the central nervous system.