EPA and DHA (which stand for Eicosapentaenoic Acid and Docosahexaenoic Acid respectively) belong to the Omega 3 fatty acids. They are oils derived from cold water fish and krill. They are not produced by these fish and krill but rather accumulated by the ingestion of micro-algae.
EPA’s and DHA’s primary role is to protect these fish and krill from cold water temperatures. The defining feature of fatty acids (including EPA and DHA) are their long chain carbon structures with an acidic group at the end.
What is "Omega"?
The term “omega” means they have a double bond and the 3 number means that that bond is at the 3rd carbon position. They are also called polyunsaturated fatty acids meaning that they have one or more double bonds in their structure between their carbon atoms. This property makes them liquid at room and body temperature.
In contrast, saturated fatty acids, which are found mainly in animal fats (beef, butter, lard) are solids at room and body temperature which makes them more “sticky”. This property, along with the fact that they are not anti-inflammatory, makes them the culprits of cholesterol plaques in our arteries-the cause of heart attacks and strokes. The terms trans and cis saturated fatty indicate how some of the chemical bonds are aligned. Trans saturated fatty acids are worst, followed by cis fatty acids, since the trans fatty acids align themselves more readily, thus forming solids. But let’s go back to DHA and EPA.
What is DHA?
DHA comprises 50% of the weight of the membranes covering our brain cells. As our brains are mostly membranes, this is very significant. Mothers produce DHA in their breast milk and higher levels have been associated with better mental development in infants.
DHA is also essential for the development of our eyes and vision. Supplementation with DHA has also been linked to significant improvement in mental functioning in healthy individuals, especially in the elderly. Low levels have been found in patients with Alzheimer’s disease. DHA has been shown to slow down the shortening of telomeres, which are markers of cellular aging.
What is EPA?
EPA, on the other hand, is a potent anti-inflammatory and neuro-protective agent. A very significant number of human studies have shown that it is very effective for major depression, just as strong as that observed with prescription anti-depressive medications - without the accompanying side effects.
Furthermore, two well designed clinical trials have shown that EPA significantly eradicated the symptoms of schizophrenia, even to the extent that the majority of patients stopped their standard anti-psychotic medications. The length of time to achieve these results was about three months of supplementation at a high does of 1000 mg/day.
Further studies were performed with patients with Huntington’s disease, another very serious neuro-degenerative disease. Again, EPA has shown statistically significant improvement in these patients, especially with their motor (i.e. muscle) coordination.
EPA also holds great promise in patients with other neurological conditions such as mood disorders, bipolar disorder and anxiety.
But this is not the end of the story. EPA is also a potent inhibitor of platelets. Platelets help us with blood clotting when we are injured, but they also contribute to the clogging of small blood vessels - as in heart attacks and strokes. Usually, platelets are overactive, so inhibiting them helps prevent these dreaded occurrences. EPA also stops the growth of the muscular walls of blood vessels, which prevents their closure. Both platelet clogging and blood vessel narrowing contribute to cardiovascular disease. Finally, EPA is a potent anti-inflammatory agent, and as inflammation is the cause of many debilitating conditions (including cardiovascular disease, diabetes, arthritis and others), EPA helps with their prevention.
The vast majority of us do not get enough EPA and DHA in our diets. But we can fix this by taking a fish or krill oil supplement, or incorporating more cold water fish into our diets. The ideal EPA/DHA supplement should have a high level of both fatty acids in order to benefit from what both have to offer.
However, as shown above, EPA definitely shows more effectiveness for a number of serious medical conditions in our society, both for treatment as well as for prevention.
Fish oil supplements have come a long way since their introduction. Now you can decide if you want to go with an equal EPA/DHA supplement or a high EPA/low DHA supplement, or vice versa. Deciding which fish oil supplement you should take should be driven by your needs.
Choosing the best supplement
Overall, a high EPA and low DHA supplement is your best choice, unless you are a pregnant or nursing mother, an infant or a child; in this case, the higher DHA level is needed for proper brain and eye development. A high EPA level will help protect you from neuro-degenerative diseases, mood disorders and depression. As mentioned above, studies also show that EPA is also an excellent treatment modality for these serious conditions. Furthermore, EPA will also protect from atherosclerotic plaques responsible for cardiovascular disease (i.e. heart attacks and strokes). Usually, a high EPA supplement also provides some DHA for your brain’s structural needs.
The final note is that when you review the label of your fish oil supplement, pay attention to the source of the oil. It should be derived from cold water fish such as salmon, mackerel, sardines, anchovies, halibut or the little creatures called krill.
Take care and remember: prevention is key. See you next time.