BACKGROUND: Individuals with psychotic disorders, particularly schizophrenia, experience significantly elevated rates of metabolic syndrome, often linked to antipsychotic treatment. Omega-3 polyunsaturated fatty acids (PUFAs) have demonstrated cardiovascular and mood benefits, but their effects on metabolic outcomes in psychotic disorders remain unclear, with no prior systematic review dedicated to this population. METHODS: A systematic bibliographic search of randomised controlled trials and comparative studies assessing the effect of omega-3 PUFAs on metabolic outcomes in individuals with psychotic disorders was conducted. Outcomes included body mass index (BMI), waist circumference, serum triglycerides, low- and high-density lipoproteins, total cholesterol, blood glucose, and blood pressure. Seven randomised placebo-controlled trials were included in meta-analyses, with four additional open-label or non-randomised trials reviewed narratively. RESULTS: range of 31-99%), reflecting variability in study design, treatment duration, and populations. Isolated benefits were observed in first-episode psychosis, but these were not significant in pooled analyses. CONCLUSIONS: Current evidence does not support a consistent metabolic benefit of omega-3 PUFA supplementation in psychotic disorders. Given methodological variability across studies and promising subgroup findings, further large-scale, standardised RCTs with metabolic outcomes as primary endpoints are warranted. While the heterogeneity of results limits interpretability, at present, omega-3 PUFAs cannot be recommended as a metabolic risk-reduction strategy in psychosis. PROSPERO REGISTRATION: CRD420251067935.
Rainford et al. (Tue,) studied this question.