Study: Omega-3 Bioavailability Dependent on Type of Production

A team of Danish researchers believe that omega-3 bioavailability in fish oil supplements is dependent on the type of formulation. Their research was published in the September issue of Prostaglandins, Leukotrienes, and Essential Fatty Acids.

Fish oil was formulated using three different formulations: ethyl esters, free fatty acids, and reesterified triglycerides, compared to placebo. In a double-blind manner, bioavailable levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were then measured across the board.

EPA and DHA bioavailability was found to be superior from reesterified triglycerides (124%) compared to natural fish oil; meanwhile, ethyl esters were found to provide inferior bioavailability at 73% and free fatty acid (91%) did not differ significantly from natural fish oil.

Results of this study might bode well for a company like Nordic Naturals (Watsonville, CA), which offers fish oil in the form of reesterified triglycerides.

“In fish, [EPA and DHA] occur naturally in triglyceride form,” said the company in a recent press release. “To make a quality fish oil concentrate, the individual fatty acids must first be removed from the glycerol backbone. To stabilize these delicate fatty acids, they are bound to an ethyl alcohol molecule before they undergo molecular distillation to both purify and increase the amounts of EPA and DHA. Once the desired concentration is achieved, a manufacturer chooses from two distinctly different options. The first is to reattach the fatty acids to the glycerol backbone in a process known as “re-esterification” to recreate the natural triglyceride structure. The second, far less costly option is to leave the fish oil as an ethyl ester, a “new to nature” form of fatty acid.”

Check out the study abstract here.