Research Spotlight on Omega Oils

Natural Triglyceride Form Fish Oil vs. Ethyl Ester Form

 

 

No matter what the nutrition, it's always about absorption!

Natural Triglyceride Form Fish Oil vs. Ethyl Ester Form

In response to the well-established benefits of the long chain omega-3 essential fatty acids, EPA and DHA, and the widespread deficiency of omega-3s in the American diet, health care professionals are increasingly recommending purified fish oil as a dietary supplement. But few consumers know that there are two different molecular forms of fish oil supplements on the market: the synthetic ethyl ester form, and the natural triglyceride form.

EPA and DHA naturally occur in the triglyceride form in fish. A triglyceride consists of a glycerol “backbone” linked to three fatty acids. To manufacture a fish oil concentrate, the fatty acids are removed from the backbone and undergo processing. The manufacturer must then choose to either 1) use enzymes to reassemble the fatty acids into the natural triglyceride structure or 2) react the free fatty acids with ethanol, resulting in an ethyl ester fatty acid, which is the less costly option. The majority of concentrated EPA and DHA products on the market are in the ethyl ester form.

Although current research does not reveal scientific consensus on the distinction between these two forms of fish oil supplements, it has been established that several differences exist in how the body utilizes ethyl ester versus triglyceride EPA and DHA. The ethyl ester fatty acid does not naturally occur anywhere in the human diet and may not mimic the physiologic activity of triglycerides. Many clinical studies on bioavailability, stability, and other comparative issues suggest that the triglyceride form is both better absorbed and assimilated as well as more molecularly stable than ethyl esters1–9. In addition, the established therapeutic value of EPA and DHA is based on data from several large-scale epidemiological studies, all of which are based on natural triglyceride fish oils10–15. Thus, although the scarcity of the data does not allow for definitive conclusions, evaluating these issues before relying on a synthetic form of EPA and DHA seems advisable.

Omega 3,6,9 Oils

 

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9 Website USPTO Patent Full-Text and image database. Accessed June 2007 [http://patft.uspto.gov/netacgi/nph-Parser?u=%2Fnetahtml%2Fsrchnum.
htm&Sect1=PTO1&Sect2=HITOFF&p=1&r=1&l=50&f=G&d=PALL&s1=5502077.PN.&OS=PN/5502077&RS=PN/5502077]
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