By:  John Wigneswaran MD

Many supplements promote the use of Krill Oil as an acceptable substitute for Fish Oil (Omega-3 fatty acids). In such instances these supplements often boast about the smaller pill size of Krill Oil. But two questions:

  1. Is it really just as good for your health?
  2. Can you substitute this for fish oil?

Fish Oil facts

Fish oil is an oil that comes from the body tissue of “oily fish”- most commonly fish like salmon, sardines or herring. Fish oils derive their health benefit from the omega-3 fatty acids it contains particularly these two:

  1. DHA (docosahexaenoic acid)
  2. EPA (eicosapentaenoic acid)

DHA and EPA have very important functions in reducing inflammation in the body and are particularly important in heart health. In fact the American Heart Association recommends the following regimen to reduce the risk of heart disease:

1000mg of omega-3 fatty acids (equivalent to 2000mg of fish oil) daily

If you are a healthy eater and can eat two oily fish meals a week then you are able to meet theses requirements. For many people who can’t do this, taking a fish oil supplement may help.

What is Krill and Krill Oil?

Krill are shrimp-like crustaceans that are a source of certain omega-3 fatty acids.  Krill oil also contains additional substances such

  1. Astaxanthins
  2. Vitamin A
  3. Vitamin E
  4. Vitamin D

As of 2009, the evidence for the use of krill oil in human diseases is very limited (only 13 sources in the scientific literature!) and none exists for its use in patients with kidney disease.  There are currently no scientific guidelines or medical associations that recommend the use of Krill oil as a substitute.

In addition, while substances like astaxanthins may be of benefit as an antioxidant, there is currently no real evidence of benefit.  Interestingly, from data presented in the journal Nature in 2004, the effects of global warming may be reducing krill populations in the Antarctic (Atkinson, November 4, 2004).  This lead one to ask why should we further kill these shrimp reserves for something that hasn’t been proven to work?

In addition, while Krill Oil touts the smaller pill size it also contains very little omega-3 fatty acids in each pill. Typically they contain about 90mg per Krill Oil soft gel.   Thus, to align with the American Heart Association recommendations of 1000mg per day you would need to consume more than 10 Krill Oil soft gels daily, making it far more expensive than a quality Fish Oil supplement.

So Which Should You Take?

At the present time, there is significantly more clinical evidence on the use of omega-3 fatty acids derived from fish oil. By the fact that the American Heart Association recommends 1000mg of Omega-3 fatty acids (Fish Oil) daily and not Krill Oil to help prevent the risk of worsening heart disease, this provides a good path to follow. Remember to always discuss your supplement use with your physician.

Bibliography

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  2. Cleland, Leslieg; James, Michaelj; Proudman, Susannam (2006). “Fish oil: What the prescriber needs to know”. Arthritis Research & Therapy 8 (1): 679–81. doi:10.1186/ar1876. PMC 1526555. PMID 16542466.
  3. Venturi S, Donati FM, Venturi A, Venturi M (2000). “Environmental iodine deficiency: A challenge to the evolution of terrestrial life?”. Thyroid 10 (8): 727–9. doi:10.1089/10507250050137851. PMID 11014322.
  4. Venturi S, Venturi M (2007). “Evolution of Dietary Antioxidant Defences”. European Epi-Marker 11 (3): 1–12.
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