Krill Oil vs Fish Oil: Why You Could Benefit from Both

Holli Ryan RD, LD/N

Krill oil and fish oil are both healthful, omega-3 fatty acid containing marine oils derived from ocean-dwelling animals. Krill (Euphausia superba) are shrimp-like crustaceans that have gained in popularity as a means of omega-3 supplementation in recent years. Omega-3 containing fish oils are sourced from a variety of fatty fish such as anchovy, pollock, cod, or salmon. Let’s compare and contrast the two sources and determine if one is better than the other.

krill oil vs fish oil

Pros of Fish Oil
  • Cost and Availability – fish oil is generally more widely available and cost effective.
  • Amount of Omega-3 Fatty Acids – fish oil offers more EPA and DHA compared to the same amount of krill oil. While some research suggests that the triglyceride (TAG) form may be better absorbed, the ethyl ester (EE) form offers the best value at the highest concentration of omega-3 fatty acids.
  • More, long-term scientific studies (especially the EE form) – Fish oil even has pharmaceutical-funded clinical trials behind it that proved its efficacy and as a result, is available as a prescription medication called Lovaza.
Anchovy is a good source of the omega-3 fatty acids EPA and DHA.

Pros of Krill Oil

  • Unique Chemical Structure – the omega-3 fatty acids are primarily bound to phospholipid
    • Absorption – phospholipids may improve absorption
    • Additional Benefit - Studies show that the fatty acids found in krill oil are particularly effective for joint health.
  • Antioxidant – contains astaxanthin (reddish pigment) which may benefit cognitive health, skin health, and more.

Antarctic Krill contains omega-3 fatty acids EPA, DHA, and phospholipids.

Why supplement with omega-3 fatty acids at all? Many typical modern diets do not provide enough omega-3 fatty acids. Whether you choose fish, krill, or both as your source of omega-3, both will provide the benefits listed below if taken in the right amounts. Life Extension recommends 1400 mg of EPA and 1000 mg of DHA daily to support optimal health.

Related Article: Dangers of an Omega-6 to Omega-3 Imbalance

Benefits of Omega-3 Fatty Acids: EPA & DHA

  • The omega-3 fatty acids EPA and DHA work together to promote a healthy inflammatory response to support whole-body health.1
  • Eicosapentaenoic acid (EPA) is especially important for healthy inflammatory pathways and for cardiovascular health.2-4
  • Docosahexaenoic acid (DHA) is the predominant fatty acid in retinal, neuronal and brain cell membranes; it is especially important for visual and neurological (brain and nervous system) health.5-7
  • Together, EPA and DHA support cardiovascular health, heart function and normal heart rhythm.8,9
  • Omega-3 ethyl esters (EE) have been shown to lower triglyceride levels.10-12
  • Omega-3 fatty acids are important for healthy brain function and cognitive development throughout the lifespan.13-15

Benefits of Krill Oil

  • Krill is a natural source of the antioxidant carotenoid astaxanthin and EPA and DHA that are mostly bound to phospholipids (like phosphatidylcholine).
  • Approx. 60-70% of the omega-3 fatty acids in krill oil are bound to phospholipids.16
  • Phospholipid-bound omega-3s may be more efficiently absorbed than unbound.16
  • Like fish oil, krill offers benefits for cardiovascular (possibly to a greater extent than fish) and brain health.17-19
  • Krill oil may provide more targeted support for the nervous system because the omega-3s it provides are more rapidly taken up into red blood cells (RBCs) which may then be quickly incorporated into brain cells.20
  • Krill has been shown to benefit joint health.21

The Bottom Line: Krill or Fish Oil?

Combining traditional fish oil with krill oil may offer additional health benefits beyond supplementing with either alone. The two sources complement each other and offer a person more comprehensive health benefits.22 The ideal supplementation strategy would be to combine the various fish oil forms (EE and TAG) along with krill oil (phospholipid). This combination allows one to receive optimal amounts of EPA and DHA while taking advantage of the full spectrum of benefits from these three unique omega-3 forms, in addition to the antioxidant astaxanthin from krill. More studies are needed to confirm the absorption characteristics of phospholipid bound omega-3 in krill and how this relates to increasing EPA and DHA blood levels. Lab testing is a good way to determine if the type/form you are taking is raising your blood levels.

Holli Ryan is a Registered and Licensed Dietitian/Nutritionist.
About the Author: Holli Ryan is a Registered and Licensed Dietitian/Nutritionist, health and wellness advocate, and blogger/writer based in South Florida. She is a Florida International University graduate and member of the Academy of Nutrition and Dietetics. Her focus as a dietitian is disease prevention and management of health through nutrition education and customized suggestions. Holli believes that quality dietary supplements are an essential tool that have a variety of applications, from maintaining good health to managing chronic disease.


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