Enhanced increase of omega-3 index in response to long-term n-3 fatty acid supplementation from triacylglycerides versus ethyl esters.
Level 2 - randomized trial
Individual randomized controlled trial in humans
PubMed 21063431 · doi:10.1038/ejcn.2010.239
What was done
A double-blind, placebo-controlled randomized trial evaluated the bioavailability of two forms of omega-3 fatty acids over 6 months in 150 volunteers. Participants were assigned to one of three groups taking four capsules daily: (1) re-esterified triacylglycerides (rTAG; 1.01 g EPA + 0.67 g DHA daily), (2) corn oil placebo, or (3) ethyl esters (EE; 1.01 g EPA + 0.67 g DHA daily). The omega-3 index (red blood cell membrane EPA+DHA percentage) was measured at baseline, 3 months, and 6 months.
What was found
Both omega-3 supplementation groups experienced significant increases in their omega-3 index from baseline to 3 and 6 months (P < 0.001). The rTAG group achieved a significantly greater relative increase than the EE group at 3 months (186% vs. 161%, P < 0.001) and at 6 months (197% vs. 171%, P < 0.01).
Why it matters
This study shows that the chemical form of omega-3 supplements affects tissue incorporation, with re-esterified triacylglycerides raising red blood cell EPA and DHA levels faster and to a greater extent than ethyl esters at equivalent doses.
Limits
The abstract reports relative percentage increases rather than absolute baseline or post-intervention omega-3 index values. Participant characteristics, baseline dietary omega-3 intake, adherence rates, and placebo group values are not detailed in the abstract.
Cited by
- supports Ethyl ester formulations of omega-3, such as Lovaza and Vascepa, have lower bioavailability and incorporate into cell membranes less readily than triglyceride forms.