Evidence Level
Fish oil is a well-researched nutritional supplement with substantial evidence supporting its cardiovascular benefits. The REDUCE-IT trial (Bhatt et al., 2019) demonstrated that 4g of icosapent ethyl, a purified form of EPA, reduced major adverse cardiovascular events by 25% in statin-treated patients with elevated triglycerides. A Cochrane review by Abdelhamid et al. (2020) confirmed omega-3 fatty acids effectively lower triglycerides and may reduce coronary heart disease events and mortality, though effects on total mortality were less clear.
Beyond cardiovascular health, fish oil has shown efficacy in mental health. Liao et al. (2019) meta-analyzed 26 RCTs, finding significant antidepressant benefits, particularly with EPA-dominant formulations at doses exceeding 1g/day. Anti-inflammatory mechanisms of omega-3 fatty acids were elucidated by Calder (2017), who explained that EPA and DHA compete with arachidonic acid for COX-2/LOX enzymes, generating specialized pro-resolving mediators that actively resolve inflammation.
Recent studies highlight additional benefits. Zhou et al. (2022) found fish oil supplementation significantly reduced CRP levels in hemodialysis patients, particularly in those with elevated baseline CRP. Khoshnoudi-Nia et al. (2022) reviewed encapsulation methods, identifying electrohydrodynamic techniques as highly efficient for fish oil delivery using polysaccharide-protein walls. These findings underscore the versatility and continued relevance of fish oil research across diverse health applications.
Fish oil has also been studied in specific populations. Rajati et al. (2024) conducted a systematic review and meta-analysis of 16 studies, finding that omega-3 supplementation and fish oil significantly reduced the risk of total preeclampsia (RR: 0.63; P=0.027) and severe preeclampsia (RR: 0.45; P=0.011). Pradelli et al. (2025) found that fish oil parenteral nutrition (FO-PN) reduces infection risk in hospitalized non-ICU patients, based on a systematic review/meta-analysis of 29 RCTs.
In summary, fish oil has demonstrated cardiovascular benefits, anti-inflammatory effects, and potential applications in mental health and specific populations. Continued research underscores its versatility and relevance across diverse