Health Canada, the World Health Organization and the American Heart Association all recommend an increased daily intake of omega-3. That is because omega-3 is essential from infancy to old age for normal growth and development, but cannot be produced by the human body.
Omega-3 essential fatty acids are a group of polyunsaturated acids that include three essential parts: 1) eicosapentaenoic acid (EPA); 2) docosahexaenoic acid (DHA); & 3) docosapentaenoic acid (DPA). All three omega-3 essential fatty acids circulate in the blood stream under normal conditions. It is therefore important to supplement with an omega-3 product that contains all three omega-3 essential fatty acids (EPA, DHA and DPA).
Chemical Composition of Seal Oil
Seal oil is naturally available as a triglyceride, which is ideal for superior absorption. Most fish oils are ethyl ester concentrates that have been chemically altered to yield higher levels of EPA and DHA. This process makes fish oil concentrates less effective for absorption than seal oil. Faster absorption ensures that more omega-3 essential fatty acids are absorbed and used by the body.
The distribution of fatty acids in seal oil differs from that of fish oil. Chemical analysis of the structure of seal oil shows that EPA, DHA and DPA are mainly distributed in the first and third position, compared to fish which is mainly in the second position.
Seals, like humans, are mammals. Therefore, seal oil triglycerides have the same first and third distribution of fatty acids as human triglycerides. The fact that seal oil triglycerides have the same structure as the triglycerides of humans ensures that seal oil is readily digested and the omega-3 fatty acids routed by the same pathways to where they are most needed (Ackman, 1988). The position of fatty acids in seal oil is considered superior to fish oil because it allows for faster digestion, and ultimately absorption, of EPA, DHA and DPA (Shahidi, et al., 1996) (Christensen M, et al., 1996).
Importance of DPA
Unlike fish oil, seal oil contains docosapentaenoic acid (DPA). DPA is found to circulate in the blood stream under normal conditions. However, we lose DPA as we age and can only replace it through our diet.
Numerous studies have highlighted the importance of DPA:
- DPA was found to be 10 times more effective than EPA in repairing damaged vessel walls (Kanayasu-Toyoda, et al., 1996)
- All omega-3 fatty acids from marine mammal sources are considered to be readily incorporated into body tissues (Ackman, 1988)
- Men with higher levels of DPA plus DHA in their blood serum lipid had 44% reduced risk of acute coronary events (Rissanen, et al., 200)
- DPA has a potent inhibitory effect on angiogenesis (Tsuji, et al., 2003)
- DPA increases total serum omega-3 (Conquer, et al., 1999)
- DPA found to reduce prostacyclin production in endothelial cells (Benistant, et al., 1996)
- DPA has anti-inflammatory activity and enhances the effects of DHA (Neuroth, et al., 2010)
- DPA is recognized as an essential nutrient by the Ministry of Health in Australia and New Zealand (Link)
Safety of Seal Oil
Triglyceride Compared to Ethyl Ester
Most fish oils are not natural triglycerides, but ethyl esters (concentrates). The ethyl ester process concentrates EPA and DHA levels in the fish oil to yield higher amounts of both essential fatty acids. This process also reduces the absorption capabilities of fish oil, thus making ethyl ester fish oils less effective for absorption than natural triglyceride seal oils (Dyerberg, et al., 2010) (Mann, et al., 2010).
Re-esterfied triglycerides are usually fish oil concentrates that have been altered back to the triglyceride form. While this chemical form is superior to the ethyl ester from, it is not as effective for absorption when compared to the natural triglyceride chemical form.
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