The triglyceride form—the natural, bioidentical form of omega-3 fatty acids found in fish—has significantly superior absorption compared to semi-natural ethyl ester forms commonly used in fish oil products.
In a 150-patient, head-to-head study examining the ability of fish oil to raise omega-3 index, the triglyceride form had 15% better red blood cell (RBC) saturation than the ethyl ester form.1
1Neubronner J, Schuchardt JP, Kressel G, Merkel M, von Schacky C, Hahn A. Enhanced increase of omega-3 index in response to long-term n-3 fatty acid supplementation from triacylglycerides versus ethyl esters. Eur J Clin Nutr. 2011 Feb;65(2):247-54.