This systematic review and meta-analysis of 96 clinical trials published before February 2025 examined how EPA:DHA dosing ratios and total doses affect blood fatty acid profiles and inflammation. Supplementation increased EPA and DHA levels, reduced arachidonic acid and inflammatory markers like CRP, TNF-α, and IL-6, with optimal effects from ratios <1.0 and doses of 1-3 g/day. Findings highlight the need to optimize omega-3 formulations for better bioavailability and anti-inflammatory benefits.

This peer-reviewed study investigated six weeks of EPA-rich or DHA-rich omega-3 supplementation in endurance-trained males, showing significant increases in the Omega-3 Index and improvements in submaximal exercise heart rate and perceived exertion compared to placebo. Both supplements altered exercise physiology positively, with evidence suggesting EPA may drive reductions in perceived exertion. The double-blind design confirms efficacy in elevating omega-3 levels above recommended thresholds.

Researchers found that omega-3s like EPA and DHA reduce colorectal tumors in mice via the ALOX15 enzyme, with EPA (including in FDA-approved Lovaza) more effective than DHA, especially in ethyl ester and free fatty acid forms. Without active ALOX15, supplements may increase tumor risk, raising questions for human use in colon cancer prevention. The study urges consulting doctors before using fish oil and explores boosting ALOX15 for enhanced benefits.