Quality fish oils are made up of both EPA and DHA and come in various levels of concentration. Some more concentrated in EPA, others in DHA. These are explicitly designed for different health conditions. These different types of omega-3s are also available in various forms; Triglyceride (TG) and Ethyl Ester (EE). One of the most frequent questions that come up is, which is best, and why?
Ethyl esters are produced by reacting crude oil with industrial alcohol (Ethanol) to create concentrated omega-3s. While in this form, the natural glycerol backbone of the essential fatty acid has been replaced with an ethanol molecule. No longer in its natural state, these EEs become highly susceptible to oxidation.
Studies have shown that EE's can oxidize up to 33% faster than omega-3s in TG form, and consuming oxidized omega-3s can have a detrimental effect on your health. In addition to this, consumed ethyl esters are processed in the liver where the ethanol molecule is drawn off where the body must now re-esterify the omega-3 so that it may be absorbed. This results in a much lower bioavailability compared to the direct intake of omega-3 in the triglyceride form.
There are negative side effects that can be related to the consumption of EE's as any alcohol is filtered through the liver. The most common side effects are reflux (fish burps), upset stomach, flu-like symptoms, back pain, and in some cases, skin rashes. These are the results of the toxicity of the ethanol being separated and released into the body.
There are several ways to produce triglyceride omega-3s. All involve molecular distillation. Some are done hot, and some are done cold. All will include some form of fractioning, either with alcohol or CO2 extraction.
The main goal will be a re-esterification process where the fatty acids are reattached to a glycerol backbone to achieve its natural state. This is very important because omega-3s in a TG form are much more stable than EE's and will not oxidize as quickly. Omega-3s in their natural state, are much more bioavailable and can easily be absorbed in the gut and transported in the blood. Furthermore, TG based omega-3s are absorbed up to 48% better than EEs. There are virtually no adverse side effects associated with consuming omega-3s in the triglyceride form.
To obtain the maximum benefit of omega-3s, humans should always be consuming them as close to their natural state as possible. Research clearly shows that TG omega-3s are more readily digested, carry lower levels of oxidation, and are assimilated better than the ethyl esters, which are still a very recent addition to our food supply.
So why aren't all fish oils in TG form? It's not that complicated. It takes significantly longer to produce high-quality omega-3s in TG form, and therefore the cost for the company manufacturing them is also much higher. On average, TG oils will cost companies roughly 40% - 50% more to produce.
If you are looking to achieve positive results from your omega-3s, always make sure you are getting them in a triglyceride form.
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