THE MAIN DIFFERENCES BETWEEN EPA AND DHA
Both are classified as long-chain fatty acids, however the benefits of both are often very different, which is why we need both. But let's see in more detail:
The purpose of EPA is to help reduce cellular inflammation, because EPA is an inhibitor of the enzyme delta-5-desaturase (D5D) that produces AA * (1), the greater the intake of EPA, the lower the production of AA. DHA is not an inhibitor of this enzyme.
The various enzymes (COX and LOX) that produce the pro-inflammatory eicosanoids can accommodate both AA and EPA, which is not the case with DHA because of its larger spatial size, which makes DHA a poor substrate for these enzymes -key. As such, DHA has a reduced impact on cellular inflammation, while EPA can have a powerful impact.
Finally, due to low levels of EPA in the brain, it is considered to be of little importance for brain function. However, this is fundamental for the reduction of neurological inflammation, competing against AA for access to the same enzymes necessary for the production of inflammatory eicosanoids. However, once EPA reaches the brain it is quickly oxidized, which is not the case with DHA. The only way to control cellular inflammation in the brain is to maintain high levels of EPA in the blood. It is for this reason that all studies on depression, brain trauma have shown that EPA is superior to DHA
Benefits of DHA
According to Dr. Barry Sears, the main benefit of DHA lies in its unique spatial characteristics. As mentioned earlier, the additional double bonds and length of DHA compared to EPA means that it takes up a lot more space in the membrane. Although this increase in spatial volume makes DHA a poor substrate for phospholipase A2, as well as the enzymes COX and LOX, it does a great job on more fluid membranes (especially those in the brain). This increase in membrane fluidity is critical for synaptic vesicles and the retina of the eye, because it allows receptors to rotate more effectively, thereby increasing the transmission of signals from the membrane surface to the inside of nerve cells. That is why DHA is a critical component of these parts of the nerves (7). On the other hand, the myelin membrane is essentially an insulator so that relatively little DHA is found in that part of the membrane.
EPA and DHA can do different functions, so we need both. If your goal is to reduce cell inflammation, then you will probably need more EPA than DHA. How much more? Probably double the levels.
Stay in the zone, your health thanks you!
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