Both krill oil and fish oil are excellent sources of omega-3 fatty acids. While these two supplements may provide a range of benefits, a few key differences set them apart. Besides being sourced from different types of marine life, there are several other subtle differences between the two.  

Read on to learn more about the difference between krill and fish oil, their benefits and how to incorporate them into your diet.  

Fish oil vs krill oil - where do they come from? 

Perhaps the most obvious difference between fish and krill oil is that they’re sourced from two different marine animals. Fish oil is typically sourced from oily fish, like anchovies, tuna, salmon and mackerel. Fish oil often has a yellow or golden appearance. Krill oil, on the other hand, comes from a small crustacean known as krill and has a distinctive red colour. 

If you’re trying to decide whether fish oil or krill oil is more suited for you, here are a few of the benefits these two oils offer. 

What are the benefits of krill vs fish oil 

While krill and fish oil contain omega-3 fatty acids, specifically eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)¹, these two supplements provide their own unique health benefits. 

Benefits of krill oil 

Thanks to the composition of krill oil, it can offer: 

•  The vibrancy of krill is due to pink-orange pigment called astaxanthin², 
• Relieves knee pain and stiffness and increases knee physical function in mild to moderate osteoarthritis³, 
• Support cardiovascular system and heart health, and 
• Supports brain and eye health function. 

Benefits of fish oil 

Similarly, there’s evidence to suggest fish oil may offer its own health benefits, like: 

• Supporting eyesight health, 
• Support healthy cardiovascular system. 
• Maintaining, brain development in breast fed healthy infants and 
• Supporting join health. 

Is krill oil better than fish oil when it comes to use in the body? 

So, is krill oil the same as fish oil? In short, no. Due to their different compositions, krill oil and fish oil are absorbed differently by the body⁴. While krill oil’s omega-3 fatty acids are bound to phospholipids, the omega-3s in fish oil are typically bound to triglycerides. 

Here’s how they both compare.  

Phospholipids in krill oil 

The omega-3 fatty acids in krill oil are bound to phospholipids, which are fats that are essential components of cell membranes. Phospholipids are molecules with a combination of regions that lack affinity to water and are attracted to water. This means they’re able to interact more readily with the aqueous environment of the gastrointestinal tract, making them more soluble and easier for the body to absorb⁵. 

Triglycerides in fish oil 

When it comes to fish oil, the omega-3s are bound to triglycerides rather than phospholipids. Triglycerides are a type of fat that’s found in your blood⁶. When you eat, your body converts any calories it doesn't need to use right away into triglycerides, which are then stored in your cells. In between meals, your hormones release these triglycerides. 

Triglycerides have a different molecular structure than phospholipids. While they’re still efficiently absorbed, the body uses these forms differently⁷. 

Does krill oil or fish oil taste better? 

It is common to find Vitamin E (tocopherol) added to Krill and fish oil tocopherol it helps protect the oil from going rancid over time, making it more stable. Krill is often known to have a less fishy smell and aftertaste 

Should you take both fish oil and krill oil?  

While you might be deciding between krill or fish oil, Due to the different compositions and benefits of these supplements, it’s important to check with your doctor or a qualified health professional before adding a new supplement to your daily routine. Especially if you already take certain medications or other supplements. 

What is the best way to get fish oil or krill oil into your diet? 

One of the easiest ways to get more omega-3 fatty acids into your diet is to eat more oily fish, like salmon, tuna, mackerel, sardines, herring and trout. It’s recommended that adults eat 2-3 servings of fish a week to reach their intake of omega-3s⁸. Alternatively, you might like to take a fish oil supplement to support your daily omega intake. 

One key difference between fish oil and krill oil is that krill oil isn’t widely consumed as a food, so you might like to consider adding a supplement to your diet.  

For more information on the benefits of omega-3s and other beneficial supplements, check out the Swisse Wellness Hub.  

References: 

1. Backes JM, Howard PA. Krill Oil for Cardiovascular Risk Prevention: Is It for Real? Hospital Pharmacy [Internet]. 2014 Nov 1;49(10):907–12. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4252213/ 
2. Zadeh-Ardabili PM, Rad SK. Anti-pain and anti-inflammation-like effects of Neptune krill oil and fish oil against carrageenan induced inflammation in mice models: Current statues and pilot study. Biotechnology Reports [Internet]. 2019 Jun [cited 2019 Nov 15];22:e00341. Available from: https://www.sciencedirect.com/science/article/pii/S2215017X19301006 
3. Sampalis F, Bunea R, Marie, Pelland F, Kowalski O, Duguet N, et al. Original Research Krill Oil & PMS Evaluation of the Effects of Neptune Krill OilTM on the Management of Premenstrual Syndrome and Dysmenorrhea. Alternative Medicine Review [Internet]. 2003 [cited 2024 Apr 30];8(2). Available from: https://altmedrev.com/wp-content/uploads/2019/02/v8-2-171.pdf 
4. Ulven SM, Holven KB. Comparison of bioavailability of krill oil versus fish oil and health effect. Vascular Health and Risk Management. 2015 Aug;511. 
5. Ramprasath VR, Eyal I, Zchut S, Shafat I, Jones PJH. Supplementation of krill oil with high phospholipid content increases sum of EPA and DHA in erythrocytes compared with low phospholipid krill oil. Lipids in Health and Disease [Internet]. 2015 Nov 4 [cited 2019 Aug 8];14(1). Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4632328/ 
6. Bornfeldt KE. Triglyceride lowering by omega-3 fatty acids: a mechanism mediated by N-acyl taurines. Journal of Clinical Investigation. 2021 Mar 15;131(6). 
7.  Köhler A, Sarkkinen E, Tapola N, Niskanen T, Bruheim I. Bioavailability of fatty acids from krill oil, krill meal and fish oil in healthy subjects–a randomized, single-dose, cross-over trial. Lipids in Health and Disease. 2015 Mar 15;14(1). 
8. Protein and heart health | Heart Foundation [Internet]. Heartfoundation.org.au. 2016. Available from: https://www.heartfoundation.org.au/healthy-living/healthy-eating/protein-and-heart-health