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The effects of vitamin and mineral supplementation on symptoms of schizophrenia: a systematic review and meta-analysis

Published online by Cambridge University Press:  16 February 2017

J. Firth ,
B. Stubbs ,
J. Sarris ,
S. Rosenbaum ,
S. Teasdale ,
M. Berk  and
A. R. Yung
J. Firth*
Affiliation:
Division of Psychology and Mental Health, University of Manchester, Manchester, UK
B. Stubbs
Affiliation:
Physiotherapy Department, South London and Maudsley NHS Foundation Trust, London, UK Health Service and Population Research Department, Institute of Psychiatry, Psychology and Neuroscience, King's College London, UK
J. Sarris
Affiliation:
Department of Psychiatry, University of Melbourne, The Melbourne Clinic, Melbourne, Australia Centre for Human Psychopharmacology, Swinburne University of Technology, Hawthorn, Australia
S. Rosenbaum
Affiliation:
Department of Exercise Physiology, School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, Australia
S. Teasdale
Affiliation:
Keeping the Body in Mind Program, South Eastern Sydney Local Health District, Sydney, Australia School of Psychiatry, University of New South Wales, Sydney, Australia
M. Berk
Affiliation:
Deakin University, IMPACT Strategic Research Centre, School of Medicine, Victoria, Australia Department of Psychiatry, Florey Institute of Neuroscience and Mental Health, Orygen, The National Centre of Excellence in Youth Mental Health and Orygen Youth Health Research Centre, University of Melbourne, Australia
A. R. Yung
Affiliation:
Division of Psychology and Mental Health, University of Manchester, Manchester, UK Greater Manchester West NHS Mental Health Foundation Trust, Manchester, UK
*
*Address for correspondence: Mr J. Firth, Institute of Brain, Behaviour and Mental Health, University of Manchester, Room 3.306, Jean McFarlane Building, Oxford Road, Manchester M13 9PL, UK. (Email: [email protected])
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Abstract

Background

When used as an adjunctive with antipsychotics, certain vitamins and minerals may be effective for improving symptomatic outcomes of schizophrenia, by restoring nutritional deficits, reducing oxidative stress, or modulating neurological pathways.

Method

We conducted a systematic review of all randomized controlled trials (RCTs) reporting effects of vitamin and/or mineral supplements on psychiatric symptoms in people with schizophrenia. Random-effects meta-analyses were used to calculate the standardized mean difference between nutrient and placebo treatments.

Results

An electronic database search in July 2016 identified 18 eligible RCTs, with outcome data for 832 patients. Pooled effects showed that vitamin B supplementation (including B6, B8 and B12) reduced psychiatric symptoms significantly more than control conditions [g = 0.508, 95% confidence interval (CI) 0.01–1.01, p = 0.047, I 2 = 72.3%]. Similar effects were observed among vitamin B RCTs which used intention-to-treat analyses (g = 0.734, 95% CI 0.00–1.49, p = 0.051). However, no effects of B vitamins were observed in individual domains of positive and negative symptoms (both p > 0.1). Meta-regression analyses showed that shorter illness duration was associated with greater vitamin B effectiveness (p = 0.001). There were no overall effects from antioxidant vitamins, inositol or dietary minerals on psychiatric symptoms.

Conclusions

There is preliminary evidence that certain vitamin and mineral supplements may reduce psychiatric symptoms in some people with schizophrenia. Further research is needed to examine how the benefits of supplementation relate to nutrient deficits and the impact upon underlying neurobiological pathways, in order to establish optimal nutrient formulations for improving clinical outcomes in this population. Future studies should also explore the effects of combining beneficial nutrients within multi-nutrient formulas.

Keywords

Adjunctivedietfoodnutritionpsychosis
Type
Review Article
Information
Psychological Medicine , Volume 47 , Issue 9 , July 2017 , pp. 1515 - 1527
Copyright
Copyright © Cambridge University Press 2017 

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