Krill Oil Vs Fish Oil - What Are The Differences?

Krill Oil Vs Fish Oil - What Are The Differences?


Fish oil has been a vital health supplement ever since scientists discovered the immense health benefits of its Omega -3 fatty acids (related article). However, overreliance, as well the ongoing concerns of high levels of oxidation through poor transport and storage, has made people look elsewhere for backups. Krill oil plays a crucial role in providing similar Omega-3 fatty acids. Both krill oil and the fish oil comprise the same Eicosapentaenoic acid (EPA) and Docosahexaenoic acid (DHA) Omega-3 fatty acids. Omega 3s are primarily linked to joint, cognitive, and cardiovascular health, among other health benefits.  

Differences between Krill Oil and Fish Oil

There are distinct differences between krill oil and fish oil right from their original sources, to the overall amount of health properties they provide.

Let's dive in.

Environment and Sourcing:

Fish oil is extracted from different types of cold-water oily fish, including sardines, salmon, herring, mackerel, and anchovies. While some companies apply sustainable fish-farming practices, others do not. Instead, there have been reported cases on aggressive fishing methods (Source).

There have also been growing concerns in the scientific world of accumulation of toxins due to the industrial chemicals which are usually released in the water.  

Krill oil, on the other hand, is extracted from krill. These are tiny crustacean, quite similar to shrimps. Their sourcing is from open water/ocean feeding grounds. 

Omega-3 Bioavailability

According to scientific research, both krill and fish oil possess significant amounts of the EPA and also DHA fatty acids. However, the difference is in how fast the human body can absorb each of these oils. It is proven that krill oils get utilized much faster than fish oil.  
The reason is that the fatty acid that is in krill are supplied to the body in phospholipids. Phospholipids are beneficial substances that are part of the structure of cell membranes in the body. As such, they may allow the omega 3s to be quickly released into the bloodstream. On the contrary, the EPA and DHA acids in the fish oils are delivered in triacylglyceride, which takes much longer to distribute the acids in the bloodstream, indicating a much slower absorption rate (Source).

More Than Just Omega-3

Krill oil also contains two powerful antioxidants, astaxanthin and tocopherol, which is a form of Vitamin E. These compounds are quite useful in providing protection from oxidative stress and inflammation (related article).  An interesting area of research is in optimising our mitochondria - the powerhouses of our cells. Astaxanthin protects our mitochondria from damage and makes them work better (Source).

Another compound is choline, which is quite similar to Vitamin B, and known to reduce homocysteine (Source). Homocysteine is an amino acid that is frequently linked to heart disease. The compound is also an excellent transporter of a variety of lipids, and also plays a critical part in the synthesis of neurotransmitters. 

Different Health Benefits of the Krill Oil vs Fish Oil

According to scientific evidence, both the fish oil and krill oil are fantastic at improving cholesterol levels in the body. However, they also come with marked differences in terms of their overall health properties.

Krill features a lot more health benefits compared to fish oil.

For example:
Krill oil is known as an effective intervention for people who have arthritis. It can significantly reduce joint pains, stiffness, inflammation, and loss of function (Source).
It can also reduce PMS symptoms as well as painful periods. Research indicates that the oils can significantly reduce breast tenderness (Source) and joint pain that occurs during painful periods (Source).

Fish oils' Omega 3 fatty acids are known to reduce the risks associated with strokes and heart disease. But the same benefits that fish oil offers can be equally be found in krill oil. 

Getting The Dosage Right

The EPA and DHA in krill oil are more stable since they are protected by the phospholipids and astaxanthin. It has also been shown to improve blood lipids more effectively than fish oil. Gram for Gram, it seems that less is more (Source). As mentioned in our Omega 3 article, we know that athletes will need a little more omega 3 than regular folks, starting off with the minimal effective dose like 1g per day - as shown in the clinical research - would be a comfortable place to start.

Since fish oil is so fragile, the EPA and DHA it carries can be oxidised by light and heat and do us more harm than good if not they're not correctly stored.

Taking too much can also be harmful because of their blood-thinning effects. It's important to speak with your physician before trying these supplements, especially if you're already on medication.

Side Effects of the Krill Oil vs. Fish Oil

  • Most of the fish oil comes with a distinctly fishy taste, which has a pungent odour. This odour should not just be taken for granted. Instead, such strong smell can be an indication of too much oxidation.

  • High dosage of fish oils can easily lead to either Vitamin A or D toxicity. Symptoms of vitamin A toxicity include rashes, dizziness, joint pain, and fatigue.

  • Anyone allergic to shellfish should use both oils more sparingly. Caution should also be extended to those who are allergic to any types of seafood in general. You can also check out vegan omega 3s here (Amazon link).

  • The two oils can also cause some problems with the gastrointestinal tract. In this case, you experience issues such as acid reflux or heartburn, diarrhoea, stomach discomfort, and indigestion. Diarrhoea is usually experienced during the initial use of the oil and linked to its high lipid content. Remember to stick to the minimal effective dose and avoid getting nasty pants.

  • Other side effects of both oils include bad breath and a lingering unpleasant fishy taste. Luckily some omega 3 oils are 'burp free' but it's important to choose the right oil for you.

Putting It All Together

Krill oil comes along as a better supplement because of the fast rate in which it gets absorbed by the body. It means that you get to enjoy the importance of omega 3-fatty acids within a relatively short time. Krill also has other additional nutrients that can support the body in numerous different ways. 
Depending on what you're going to measure, a lower dosage of krill oils can equal the health benefits of fish oils. But the higher unit cost could be the main factor that works against krill.
Other than that, they both offer significant health benefits in their distinct ways. If you happen to be allergic to shellfish, then vegan omega 3s might be your other option. And apart from being less expensive, fish oil can easily be stored in the fridge to make it last longer and avoid as much oxidation as you can.

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