In the first part of this article, we went over what essential fatty acids, or EFAs, are and why they are so important to our health. Getting back to fish now, it is a natural rich source of the EFA called omega-3. Certain types of cold water fish like salmon and mackerel contain a lot of omega-3. Getting even more specific for a moment, fish can also contain two lesser-known but still important omega-3 EFAs called docosahexaenoic acid, or DHA, and eicosapetaenoic acid, or EPA. Salmon, mackerel, trout, sea bass, and tuna all contain these two other forms of EFAs. Sticking with our automobile analogy from the first article, EFAs are cars (general term), omega-3 EFAs are Hondas (specific example of the general term), and DHA and EPA are the Accord and the Odyssey (examples of the specific example).
As we said above while EFAs have been found to be healthy in general for the conditions listed above and more, the EFAs found in fish have been well-studied for their link to helping with cardiovascular health. For example, EFAs in fish or fish oil have been found to prevent arrhythmias. One study found that taking one gram of fish oil a day reduced arrhythmias in heart attack survivors.
There is also strong evidence that the omega-3 fatty acids in fish oil (DHA and EPA) may significantly reduce blood triglyceride levels. And the Mayo Clinic’s website reports that several additional, randomized, controlled studies have found that people who have had heart attacks and get regular amounts of fish oil (either through diet or supplements) have a reduced risk of non-fatal heart attack, fatal heart attack, sudden death, and all-cause mortality (death due to any cause). The website does point out that most patients in these studies were also taking conventional heart medications, which may suggest that fish oil may add to the effects of traditional therapies.
Interestingly, being low or deficient in EFAs has been shown to an increased likelihood of developing some of the health conditions that taking EFAs can help. Take depression for example. People who suffer from depression have been found to have lower levels of EPA and DHA.