Introduction 
Metabolic syndrome is combination of certain health states that together increase the risk of cardiovascular disease, type 2 diabetes and stroke. These health states include abdominal obesity, high blood pressure, elevated fasting glucose, high circulating triglycerides, and low HDL cholesterol. It is strongly linked to insulin resistance, chronic low-grade inflammation, and can also be associated with long-term use of certain medications such as corticosteroids or antipsychotics.
In schizophrenia for example, use of antipsychotic medication is associated with an increased risk of metabolic syndrome. In addition to the positive relationship between DHA and psychiatric symptoms in schizophrenia, the link between omega-3 fatty acids and increased cardiometabolic mortality seen schizophrenia has been researched as well.

Research findings
A trial by Pawełczyk and colleagues investigated the effects of omega-3 supplementation on cardiometabolic health indicators in persons with schizophrenia (Pawełczyk et al., 2021). A group of 71 men and women aged 16-35 with a diagnosis of first-episode schizophrenia was evenly divided and given treatment daily for 26 weeks. The treatment group (36 individuals) was given 1.32g EPA + 0.88g DHA, the placebo group (35 individuals) was given olive oil capsules. Participants were allowed to continue their existing pharmacological treatment plans, which did not differ significantly between treatment and placebo group. Before the start of supplementation, at 12 weeks, and at the end of the study, it was assessed if participants met criteria for metabolic syndrome. Metabolic syndrome is a negative cardiometabolic health indicator, which contributes to cardiometabolic mortality. In the placebo group, the amount of participants with metabolic syndrome increased at 12 and 26 weeks. In contrast, the EPA+DHA treatment group did not show an increase in prevalence of metabolic syndrome, but rather a trend towards a decrease. The authors therefore concluded that treatment with EPA + DHA has positive cardiometabolic effects in adults with schizophrenia, by offering protection against development of metabolic syndrome.
 
Reference
Pawełczyk, Tomasz, Marta Grancow-Grabka, Natalia Żurner, and Agnieszka Pawełczyk. 2021. ‘Omega-3 Fatty Acids Reduce Cardiometabolic Risk in First-Episode Schizophrenia Patients Treated with Antipsychotics: Findings from the OFFER Randomized Controlled Study’. Schizophrenia Research 230:61–68. doi:10.1016/j.schres.2021.02.012.

 
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