The Effect of Eicosapentaenoic Acid Supplementation on Depression Remission: a Double-Blind Randomized Clinical Trial

There is some evidence that omega-3 fatty acids are associated with depression. The aim of this study was to compare the effects of eicosapentaenoic acid(EPA) and placebo on mild to moderate depression. This double-blind randomized clinical trial was conducted on 54 outpatients with mild to moderate depression. Patients were randomly assigned to two groups: receiving EPA supplement or placebo. EPA and placebo groups received two identical capsules per day for 12 weeks. Each capsule contained 500 mg EPA or coconut oil. Hamilton Rating Scale for Depression(HRSD) was used to determine the severity of depression at baseline, sixth and twelfth weeks after intervention. Forty two patients(77.8%) completed the 12-week intervention. A statistically significant difference was observed in mean scores of HRSD between EPA and placebo groups at the end of the study (P=0.001). Mean scores of HRSD decreased over time in both groups so that the analysis of variance for repeated measurements showed a statistically significant time effect(F=50.55, df=1.32, P<0.0001). Also, a statistically significant treatment effect of EPA compared to placebo was observed over time (treatment*time interaction, F=12.67, df=1.32, P=0.0001). The results of this study showed the efficacy of EPA in treatment of depression, so its use is recommended as an add-on to antidepressant medications in treatment of mild to moderate depression.