Table 2.

Potential effects of omega-3 fatty acids on cardiovascular system.

Main Targets	Mechanisms	Evidence	Clinical Effect
Indirect effects: Circulating free fatty acids Circulating triglycerides Thrombotic factors Inflammatory factors	Free fatty acid availability Reduction of subclinical inflammation, detectable by measurement of the wide spectrum of inflammatory markers, anti-fibrotic effects	One successful randomized trial with icosapent ethyl (EPA derivative) in higher dose, parallel trial with reduction of coronary atherosclerotic plaques in DHA data less convincing, potential role in HFpEF (evidence from observational study based on DHA plasma levels).	Lowering plasma triglycerides Lowering blood pressure Improving endothelial function measured in peripheral vessels (mostly experimental settings in humans)
Direct effects: Cell membranes Ion channels	Membrane stabilization, including their protection against free radicals Modification of different types of ion channels	In human, mostly indirect evidence from experiments, in vitro studies. Observational studies indicating decrease of sudden death with intake of fish oil.	Experimental data In vitro studies Observational/epidemiological studies in humans

Legend: DHA: docosahexaenoic acid; EPA: eicosapentaenoic acid HFpEF: heart failure with preserved ejection fraction.