The mechanism of action by which omega-3 fatty acids lower lipids is not completely understood. However, it is thought that omega-3 fatty acids can lower the amount of very low density lipoproteins (VLDL) made in the liver, which, in turn, also lowers triglyceride levels. The reduced amount of triglycerides made in the body may also be due to the fact that omega-3 fatty acids, such as DHA and EPA, make poor templates to make triglycerides. Additionally, omega-3 fatty acids appear to interact with certain proteins in the body that help in producing triglycerides, including acyl-CoA:1,2-diacylglycerol acyltransferase and lipoprotein lipase.
Because of the healthy benefits that omega-3 fatty acids have on lipid levels, there is ongoing research being conducted to determine how omega-3 fatty acids work and the additional benefits they may have on heart disease.
Dipiro JT, Talbert RL. Pharmacotherapy: A Pathophysiological Approach, 7th ed 2008.