A new study has found that certain types of omega-3 fish oil supplements work more efficiently than others.
The study, published in Prostaglandins, Leukotrienes, and Essential Fatty Acids, revealed synthetic fish oil supplements which had been converted back to a triglyceride form work up to 50% better than other products currently on the market. According to the researchers, not only is “re-esterified triglycerides have superior bioavailability, whereas ethyl esters may have a lower bioavailability”, but “free fatty acids have medium bioavailability, which is not different from that of natural fish oil triglycerides”. Huh?
If you’re like most people who are already convinced that taking fish oil is about the smartest thing you can do for your health, that study probably doesn’t tell you a thing. In fact, I’m betting you have only one question on your mind…
Which fish oil should you take?
You see the ads on t.v. for fancy grade fish oil, you know there’s a slim chance your insurance company will actually cover it. You’ve done some homework already, and what you do know is that when it comes to fish oil, there’s a huge difference in price between brands.
What’s up with mega price differences for fish oil?
To figure out what kind of fish oil you should take and what’s the deal with all the price fluctuations, you need to know about about a few things.
Chances are, you’ve never seen the words “bioavailability”, “natural triglyceride form”, or “ethyl esters” on the bottle of fish oil you’re looking at. But, I can tell you that each of them have a lot to do with the answer to your questions!
What is Bioavailability?
Let’s start with the concept of bioavailability. According to the FDA’s Bioavailability and Bioequivalence Requirements, bioavailability is “the rate and extent to which the active ingredient or active moiety is absorbed from a drug product and becomes available at the site of action”…. but really means how easily your body can make use of the substances you stick inside.
Consider this quick example: if you start your morning with a slice of whole grain toast, and a scrambled egg with a little low-fat feta cheese and some fresh spinach – BAM! It’s pretty easy for your body to use up the carbs, protein, dairy, fiber, and other vitamins.
Now, on the other hand if you decide to have some chocolate cake for breakfast it will require much more of your body’s energy to to make use of those empty calories and over-abundant sugars.
In the same way, fish oils and other nutritional supplements can be either easy for your body to use, or require more effort. Now, it’s time to review triglycerides.
What do Triglycerides have to do with Fish Oil?
I wont bore you to death with all the chemistry here, but the take away message is that fish oil exists naturally in the form of triglycerides. That is to say, the omega-3 fatty acids found in fish oil bind or stick to glycerol molecules.
Tempting as it may seem, don’t confuse fish oil in natural triglyceride form with the bad triglycerides your cardiologist hates! Why not? For starters, the American Heart Association says high doses of omega-3 fatty acids actually lowers high triglycerides in the blood. Sure, this seems counter intuitive but it has to do with the balance of omega-6 fatty acids and the specific way your body converts fatty acids. So, we’ve covered bioavailability and triglycerides…next is ethyl esters.
What are Ethyl Esters?
Basically, anytime fish oil is molecularly-distilled it becomes an ethyl ester. Unlike fish oil in triglyceride form, the omega-3 fatty acids bond or stick to ethanol molecules.
Finally, we can go back and answer your questions!
The type of fish oil you choose - whether it’s in triglyceride or ethyl ester form – matters. A lot, actually. For a while now, we’ve known that ethyl ester type fish oils are less bioavailable than their triglyceride based counterparts. The findings from this recent study only confirm what we already knew.
What is pretty neat is that the study found that free fatty acids (these come plain old triglyceride based fish oils) work just as well as the fatty acids found in fish right out of the sea.
So, why is it that ethyl esters are still on the shelves here in the U.S.? Yep, you probably guessed it. It all boils down to money, hence the mega price differences for fish oil. After fish oil is molecularly-distilled, it can very easily be converted back into a triglyceride. It does, however, require more costs to the manufacturer.
You, the unsuspecting consumer, would never know this just by looking at your bottle of fish oil because most manufactures don’t bother to mention bioavailability, triglycerides, or ethyl esters on their products.
American Heart Association. “Fish and Omega-3 Fatty Acids”. Date Accessed: September 23, 2010.
Daniells S, “Omega-3 Bioavailability: Scientists Lift the Lid on Which Forms Work Best”. Date Accessed: September 23, 2010.
Food and Drug Administration. Code of Federal Regulations. “Bioavailability and Bioequivalence Requirements”. 21CFR320. Date Accessed: September 23, 2010
Lawson LD, et al “Human absorption of fish oil fatty acids as triacylglycerols, free acids, or ethyl esters.” Biochem Biophys Res Commun. 1988 Apr;152(1):328-35
Lawson LD, et al, “Absorption of eicosapentaenoic acid and docosahexaenoic acid from fish oil triacylglycerols or fish oil ethyl esters co-ingested with a high-fat meal.” Biochem Biophys Res Commun. 1988 Oct 31;156(2):960-3
Yang LY, et al “Lipolysis of menhaden oil triacylglycerols and the corresponding fatty acid alkyl esters by pancreatic lipase in vitro: a reexamination” J Lipid Res 1990 Jan;31(1):137-47