EPA and DHA have been researched for a gamut of health benefits, including cardiovascular, ocular, inflammatory. However in fish oil the omega-3 fatty acids are in trigyceride form, whereas in krill oil they are in phospholipid form.
The new study, published in the open access Springer journal Lipids, set out to investigate the effects of krill oil and fish oil on serum lipids and markers of oxidative stress and inflammation, and to see whether the different molecular forms – triacylglycerol and phospholipids – of omega-3 make a difference on plasma levels of EPA and DHA.
The study was carried out by researchers from Akershus University College, University of Oslo, Norway, and from Aker BioMarine. Aker’s branded Superba krill oil was used.
A total of 113 participants with normal or slightly elevated total blood cholesterol were randomised into three groups. Thirty-six were given 6 capsules of 3g krill oil a day, with 543mg of EHA + DHA; 40 were given 3 capsules of 1.8g fish oil a day, with 864mg of EPA + DHA for seven weeks. The remaining 37 received no supplementation and acted as controls.
The researchers found that there was a significant increase in plasma EPA, DHA, and DPA in both the krill oil and fish oil groups compared to the control group, and no significant differences were seen between the fish oil and the krill oil groups.
In addition, the team did not observe any statistically significant differences in changes in any of the serum lipids or the markers of oxidative stress and inflammation between the study groups.
"This study confirms that a lower dose of EPA and DHA is required when taking krill oil phospholipids, compared to the triglyceride form of omega-3," according to Hogne Vik, one of the study authors.
"In addition to improving blood levels of these essential omega-3 fatty acids, a statistically significant improvement of the HDL-cholesterol/TG ratio was demonstrated, again showing the health benefits of Superba."
Lipids 2010-11-02 http://www.springerlink.com/content/270j241473471664/
Metabolic effects of krill oil are essentially similar to those of fish oil but at a lower dose of EPA and DHA, in healthy volunteers.