Omega-3 polyunsaturated fatty acids in depression: insights from recent clinical trials

This review examines evidence from recent clinical trials on the therapeutic potential of omega-3 polyunsaturated fatty acids (PUFAs) in major depressive disorder (MDD). We focus on the effects in MDD with comorbidities, younger populations, and high-inflammation presentations.

PubMed, Cochrane, and Embase databases were systematically searched for studies published between May 2022 and May 2024. The search was conducted on randomized controlled trials using omega-3 PUFAs with participants with a clinical diagnosis of depression.Higher doses of eicosapentaenoic acid (EPA) (>1 g/day) improved measures of depression, particularly in MDD with elevated inflammation markers, comorbid cardiovascular diseases, late-life onset, and children and adolescent populations. Improvements in depressive symptoms were associated with increases in omega-3 PUFA-derived anti-inflammatory and proresolving lipid mediators. As adjuvant treatments, omega-3 PUFAs have potential benefits in mood, cognitive and metabolic functions, kynurenine and serotonin pathways, and alterations in corticolimbic functional connectivity.

While evidence suggests promise, particularly for high-dose EPA and in inflammatory MDD subtypes, more research is needed to establish optimal dosing regimens, treatment duration, and patient subgroups most likely to benefit. Future studies should focus on sex differences, long-term effects, and potential synergies with other treatments.