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December 2013

Krill Oil May Raise Omega-3 Index More than Fish Oi

A recent study suggests that krill oil may be more effective in raising the omega-3 index than fish oil.

The primary essential fatty acids in the human diet are omega-3 and omega-6 fatty acids. The optimal ratio of omega-6 to omega-3 fatty acids is 4:1, while the American diet generally provides a ratio of 20-30:1. Omega-3 fatty acids have long been known to play critical roles in growth but have more recently been suggested as providing a wide range of health benefits, several of which are well supported in literature, including reductions in the risk of coronary heart disease and regulating cholesterol. The omega-3 index measures the amount of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the red blood cells.

In a new study, researchers recruited 24 healthy individuals to assess the bioavailability of krill oil versus fish oil. The study included three treatment phases during which participants were randomly assigned to receive krill oil or fish oil, both providing 600 milligrams of omega-3 polyunsaturated fatty acids, or a placebo corn oil capsule for four weeks. Each treatment phase was separated by an eight week washout period. Krill is a spineless, shrimp-like marine organism. Like fish oil, the oil produced from krill, in particular from Antarctic krill (Euphausia superba), is rich in various compounds, including long-chain omega-3 fatty acids.

The researchers found that krill oil significantly increased both plasma and red blood cell omega-3 polyunsaturated fatty acid concentrations and significantly reduced omega-6 to omega-3 ratios when compared to fish oil. Furthermore, the omega-3 index was also significantly increased following krill oil consumption when compared to both fish oil and placebo consumption. The authors noted that changes in triglyceride and high-density lipoprotein (HDL) cholesterol concentrations, as well as adverse effects, were lacking following all treatment phases.

The authors concluded that krill oil supplementation may be more effective than fish oil supplementation for increasing the omega-3 index, and therefore may have more potential in benefiting cardiovascular health. Larger-scale, well-designed clinical trials are needed to further evaluate these findings.

For more information about integrative therapies for heart health, please visit Natural Standard's Comparative Effectiveness Database.

For more information about krill oil or fish oil, please visit Natural Standard's Foods, Herbs & Supplements Database.

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  1. Natural Standard: The Authority on Integrative Medicine. 
  2. Ramprasath VR, Eyal I, Zchut S, et al. Enhanced increase of omega-3 index in healthy individuals with response to 4-week n-3 fatty acid supplementation from krill oil versus fish oil. Lipids Health Dis. 2013 Dec 5;12(1):178.

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