Krill oil and fish oils both feature the only two omega-3 fatty acids proven essential to human life and health – the long-chain "marine” omega-3s called EPA and DHA.
The human body can use omega-3 EPA and DHA in any of the three forms in which they occur naturally in seafood and in fish and krill oils … triglyceride, phospholipid, and ethyl ester.
Likewise, all three omega-3 forms occur in the human body – which routinely converts one form to another form as needed – and all three omega-3 forms are well-absorbed and clearly beneficial.
However, triglyceride-form omega-3s – which predominate in fish and in most fish oils – appear to be better absorbed, compared with the ethyl ester omega-3s used in about 10 percent of fish oil supplements.
Key Points
  • Clinical trial supports prior signs that krill oil matches the positive effects of fish oil on blood markers of heart risk … at a one-third lower dose of omega-3s.
  • Krill oil outperformed fish oil with regard to a key heart risk factor (HDL cholesterol-to-triglycerides ratio).
  • The phospholipid-form omega-3s that predominate in krill oil appear better-absorbed than the forms found in fish oils, and may produce superior effects in certain health contexts.
(The chemical processes that almost all fish oils undergo sometimes include a step that transforms their triglyceride-form omega-3s into ethyl ester form omega-3s.)
Krill oil supplements– such as our Vital Red™ brand – are unique in that most of their omega-3s occur in the phospholipid form.
A small clinical trial from Canada, published seven years ago, suggested that krill oil might yield superior cardiovascular effects, even when it delivers substantially smaller doses of total omega-3s (Bunea R et al. 2004).
That Canadian study, while significant, could not by itself prove the superiority of krill oil for reducing heart-risk markers.
But last fall, a different krill oil company funded a new controlled clinical study in Norway.
This recent trial was designed to detect any difference in the impacts that krill oil and fish oil produce on blood markers for cardiovascular risk … including blood fat and cholesterol levels and signs of oxidation and inflammation (Ulven SM et al. 2010).
Krill oil equaled fish oil for reducing heart risk markers, and did better for some
A scientific team from Norway's Akershus University College recruited 113 people with normal or slightly elevated total blood cholesterol and/or triglyceride levels fora seven-week clinical trial.
Prior evidence points to advantages for krill oil
Ethyl ester form omega-3s predominate in most fish oils, while triglyceride-form omega-3s predominate in most whole fish … and in Vital Choice Wild Sockeye Salmon Oil.
(Fish oil obtained from the wild salmon heads – such as our Sockeye Salmon Oil – is the only kind offering significant amounts of phospholipid-form omega-3s, albeit a much smaller and more variable percent of our salmon oil's total omega-3s, compared with any krill oil.)
Preliminary but persuasive animal and human evidence suggests that the phospholipid-form omega-3s that predominate in krill oil are more easily digested and fully absorbed, compared with triglyceride-form and ethyl ester form omega-3s.
Further, a small body of animal and clinical research suggests that krill oil's phospholipid-form omega-3s yield superior effects with regard to some blood markers for heart health, and some clinical aspects of brain health and menopausal health.
Krill oil complements fish oil
Many physicians, health professionals, and scientists take our Wild Alaskan Salmon Oil.
And those we've asked say that it makes sense to take both together or alternately, for two reasons:
First, our salmon oil is dominated by the triglyceride-form omega-3s that predominate in most whole fish … and all of the epidemiological evidence that links omega-3s to heart health comes from studies comparing fish consumption with heart health.
Second, they note that wild salmon oil has a distinct fatty acid profile that may have its own unique benefits.
Finally, compared with any fish oil, the omega-3s in krill oil cost considerably more per milligram, because of the higher costs of harvest and processing krill to produce oil.
We should stress that any fish oil is very good for heart health. In fact, most of the clinical trials showing cardiac benefits from fish oil have used brands that featured ethyl ester form omega-3s.
So consider krill oil a great complement to wild salmon oil (or any fish oil) that offers a small but significant digestion and absorption edge, and certain unique health effects.
The volunteers were divided randomly into three groups:
  • Six capsules of krill oil daily (3 grams, providing 543mg of EPA + DHA).
  • Three capsules of fish oil daily (1.8 grams, providing 864mg of EPA + DHA).
  • No supplements (control group).
The total amount of EPA and DHA provided in the krill oil was 37 percent lower than the amount found in the fish oil, but produced results that were equal overall, and better in one respect.
After seven weeks, krill oil matched the effects of fish oil on a selected group of known heart risk factors.
And the krill oil did better than fish oil in one respect.
Unlike the volunteers assigned to take fish oil, those who took krill oil enjoyed a significant improvement in their ratio of HDL cholesterol to blood triglycerides.
Overall, the Norwegian trial's outcome supports the 2004 Canadian study's finding that the beneficial effects produced by the ethyl ester omega-3s in standard, refined fish oils can be produced by krill oil that provides substantially lower doses of phospholipid-form omega-3s.
Specifically, krill oil matched or exceeded the risk-reducing effects of fish oil, even though the assigned dose of krill oil provided one-third fewer omega-3s.
This study appears to provide more evidence that krill oil offers some health advantages over fish oil.
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