Fatty acids obtained from seafood differ from each other in terms of their chemical structure and physical appearance. Krill oil is found in shellfish. Fish oil is obtained from fish living in cold and deep waters (mackerel, tuna, salmon, sardine and cod oil, etc.). Fish and krill oil are useful resources for reducing heart health risk factors, for many health problems such as fat loss, inflammation, joint pain, issues related to mood levels.

 While fish oil is yellow/gold color, Krill oil has a sharp red color due to the structure of the pigment astaxanthin, which provides its antioxidant properties. Therefore, krill oil has 48 times more antioxidant properties than fish oil. Fish oil is rich in vitamins A and D, while krill oil contains vitamins A and E.

 Fish oil and krill oil are rich in EPA and DHA, which are polyunsaturated acids with important properties from an omega-3 fatty acid source. Although fish oil has a higher amount of these two types of acids than krill oil, omega-3 fatty acids are more effective in krill oil due to the differences in phospholipid structure and are better tolerated by our body. In addition, in terms of fatty acid storage, fish oil is primarily stored in the form of triglycerides; krill oil is stored as phospholipids.

 There are many studies showing that the digestion and absorption amounts of Omega 3s in the phospholipid structure are much higher than those in the form of triglycerides. While our body uses 61-64% of Omega 3 in fish oil, it uses 98% of omega 3 in krill oil.

 Because omega-3 supplements are derived from seafood, they are likely to contain heavy metals if they are obtained from sources that do not grow in clean waters. In studies, Krill oil has been found to have lower levels of heavy metals such as mercury.

Things to consider when buying supplements:

1. If there is any allergic condition to seafood, Omega 3 sourced supplements are inconvenient.

2. Attention should be paid to the use of omega-3 supplements, such as fish and krill oils, with certain medications; because if drugs such as blood thinners are used, they have properties that can affect blood coagulation.

3. Although it varies from person to person, minor side effects such as stomach discomfort, diarrhea, headache and bad breath may occur. In these cases, a doctor should be consulted.

4. In order to make sure that the Omega 3 supplement to be taken contains mercury, lead and other heavy metals, it should be checked whether the product complies with the International Fish Oil Standards (IFOS). It is essential that the correct and healthy Omega 3 supplement has a valid report from the IFOS analysis laboratory and valid for every production condition.

5. When purchasing an omega-3 product, it should be noted that the ratios of EPA and DHA fatty acids it contains are high. If possible, the sum of EPA and DHA should be at least 500 mg.

As a result;

 On the other hand, if you are going to take an omega-3 supplement for health benefit, you may consider taking krill oil because of its higher antioxidant content and bioavailability.

 Despite their differences, both krill oil and fish oil are excellent sources of DHA and EPA, and there is plenty of research to support health.


  1. Ramprasath VR, Eyal I, Zchut S, Shafat I, Jones PJ. Supplementation of krill oil with high phospholipid content increases sum of EPA and DHA in erythrocytes compared with low phospholipid krill oil. Lipids Health Dis. 2015 Nov 4;14:142. 
  2. Xie D, Gong M, Wei W, Jin J, Wang X, Wang X, Jin Q. Antarctic Krill (Euphausia superba) Oil: A Comprehensive Review of Chemical Composition, Extraction Technologies, Health Benefits, and Current Applications. Compr Rev Food Sci Food Saf. 2019 Mar;18(2):514-534. 
  3. Kroupova P, van Schothorst EM, Keijer J, Bunschoten A, Vodicka M, Irodenko I, Oseeva M, Zacek P, Kopecky J, Rossmeisl M, Horakova O. Omega-3 Phospholipids from Krill Oil Enhance Intestinal Fatty Acid Oxidation More Effectively than Omega-3 Triacylglycerols in High-Fat Diet-Fed Obese Mice. Nutrients. 2020 Jul 9;12(7):2037.