Krill oil is an extract prepared from a species of Antarctic krill, Euphausia superba. Two of the most important nutrients in krill oil are omega-3 fatty acids similar to those in fish oil, and phospholipid-derived fatty acids (PLFA), mainly phosphatidylcholine (alternatively referred to as marine lecithin). Also, antioxidant experimental egg products with krill oil likely contained astaxanthin, a natural antioxidant.
Several studies have shown toxic residues in Antarctic krill and fish, however, the United States Food and Drug Administration has accepted notices from krill oil manufacturers declaring that krill oil and products derived from it meet the standards for Generally Recognized as Safe status.
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