Onnit's krill oil is sustainably harvested from pristine Antarctic waters, and is tested to be free of toxic heavy metals that are becoming an increasing problem in other seafood based food and supplementation. Krill Oil also has several benefits over fish oil that make it a superior choice in supplementation.
If you've never heard of krill, you might not be alone. However, at an estimated 600 million tons, the biomass of these shrimp-like crustaceans more than double the biomass of human beings. The harvesting practices of krill for human consumption are tightly regulated and make a minimal impact on total krill population. Comparatively, the use of krill as a nutrient source is more sustainable than other types of fish oil, such as cod or salmon.
Both krill and fish oil contain EPA and DHA. However, the one key disparity is the content of phosphatidylcholine (PC) in krill oil. The addition of a phosphate group to the fatty acid chain permits simpler digestion in the small intestine and a more rapid incorporation into brain, lung, and liver tissues. When comparing the effects of the EPA bound to phosphatidylcholine - phosphatidylserine in krill oil as opposed to the EPA bound to triglycerides in fish oil, krill is more bioavailable.
The presence of PC in krill is one clear advantage over regular fish oil. However, either fish oil or krill can be combined with additional PC to enhance absorption and boost choline levels. In randomized clinical trials, this combination has been shown to help reduce cortisol levels in individuals with stress. The presence of phospholipids in krill oil are responsible for the increased absorption efficiency and may permit a more rapid incorporation into important tissue.