Omega-3: Krill oil vs Fish Oil vs Cod Liver Oil vs Flaxseed Oil

In this post,  we will discuss about the difference between the four very popular source of omega-3 in Malaysia and discuss briefly on how to choose the best omega-3 for you.

Amongst the four, krill oil is definitely the new kid on the block. Gaining lots of popularity in recent years.

Fish oil is probably the most common supplement in Malaysia and has been popular for many ten years.

Cod liver oil is commonly used as a supplement for kids brain development but in recent years they are slowly gaining popularity again. Flaxseed oil is another choice of omega-3 supplement for people who don’t like fish oil.

The question is:

Which one should you be using? Which one is most suitable for you?

Omega-3: Where can you get them from naturally?

Omega-3 fatty acids are a type of essential fatty acids.

Meaning our bodies can’t produce them on our own and have to get them through omega-3 foods.

Omega-3 fatty acids offer many health benefits:

  1. They help to reduce heart related conditions
  2. Improve brain health and prevent mental disorders
  3. Reduce inflammation and improve joint health
  4. Help prevent or improve fatty liver
  5. improve cholesterol profiles by reducing triglyceride levels and increase HDL levels

There are actually three types of omega-3: alpha-linolenic acid (ALA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA). DHA and EPA, which are normally the preferred source of omega-3, can be found in seafood sources such as salmon, sardines, mackarel etc. ALA, on the other hand, can normally be found in plant foods, such as nuts and seeds.

Omega-3 source, fish meal

Here’s a list of superfoods that are rich in omega-3:

  1. Mackarel (Omega-3 content: 4107 mg in one piece, or 5134 mg per 100 grams)
  2. Salmon (Omega-3 content: 4023 mg in half a fillet, or 2260 mg in 100 grams)
  3. Cod Liver Oil (Omega-3 content: 2664 mg in a single tablespoon)
  4. Herring (Omega-3 content: 3181 mg per fillet, or 1729 mg per 100 grams)
  5. Oysters (Omega-3 content: 565 mg in 6 oysters, or 672 mg per 100 grams)
  6. Sardines (Omega-3 content: 2205 mg per cup, or 1480 mg per 100 grams)
  7. Anchovies (Omega-3 content: 2113 mg per 100 grams)
  8. Caviar (Omega-3 content: 1086 mg per tablespoon, or 6789 mg per 100 grams)
  9. Flaxseeds (Omega-3 content: 2338 mg per tablespoon of seeds, 7196 mg per tablespoon of oil.)
  10. Chia Seeds (Omega-3 content: 4915 mg per ounce (28 grams))
  11. Walnuts (Omega-3 content: 2542 mg per ounce, which amounts to about 7 walnuts)
  12. Soybeans (Omega-3 content: 1241 mg in half a cup, or 1443 mg per 100 grams)

Information extracted from Healthline.

Items 1-8 are mainly sources of EPA and DHA whereas items 9-12 are sources of ALA omega-3 fatty acids.

Omega-3 capsule

How much omega-3 do I need every day? What is the daily recommended dose of omega-3?

There isn’t really a set standard for how much omega-3 you should get each day.

Some health organisations have released their own expert opinions, but they vary considerably. Overall, most of these organisations recommend a minimum of 250-500 mg combined EPA and DHA each day for healthy adults.

but for people with specific health conditions, the recommendation might vary.

Heart health: 850mg of combined EPA and DHA daily.

According to this study, this dosage helped to reduce heart attacks by 25% and sudden death by 45%. Some organisations, such as the American Heart Associations, recommend patients with heart diseases to take at least 1000mg of omega-3s a day. If you happen to also have high triglycerides level, the recommended dose is 2000-4000mg a day.

Related reading: Aging gracefully: 6 supplements recommended for seniors

Depression and anxiety200- 2200mg per day.

Pregnant and breastfeedingADDITIONAL 200mg of DHA during pregnancy and breastfeeding to help baby’s brain development

Generally, the guideline goes like this

If you take less than 2 serves of fish per week, you need to take additional omega-3 supplements.

omega-3 rich oil

Which omega-3 supplement should I get?

Most of us are not able to meet the requirement of having at least two serves of fish every week.

And that means we need to get supplements.

But which one?

As mentioned above, there are ALA rich supplements and there are EPA and DHA rich supplements.

And the preferred form of omega-3 is EPA and DHA. Unless you are a vegetarian, if you were to get a supplement, always go for one with high EPA and DHA content.

The common EPA and DHA omega-3 supplements found in Malaysia are: normal fish oil, Salmon oil, Krill oil and Cod Liver oil.

Regular fish oil: How to choose a good fish oil?

This is the most common type of fish oil you can find in Malaysia. They are normally derived from anchovy, herring, sardines and mackarel.

Most brands in Malaysia contain around 300 – 500mg of omega-3 per capsule.

To find a good fish oil:

  1. Determine how much of omega-3 you need per day
  2. Check the label and see how much omega-3 per capsule
  3. Ask about the form of fish oil
  4. Make sure the fish oil is free from toxins – especially mercury or heavy metal
  5. Other considerations e.g. odourless

Omega-3 content

Most brands would have the necessary information listed on the product label. Here’s an example:

As you can see, this brand contains 550mg of Omega-3 (330 mg of EPA and 220mg of DHA). One important thing to keep in mind is that most brands would say 1000mg on the outside, but it’s really the omega-3 content that matters. So always check the label for the omega-3 content.

Forms of fish oil

Another important consideration is the form of fish oil. There are two different forms of fish oil: Ethyl esters or triglycerides.

In ethyl ester form, one fatty acid is esterified to one ethanol molecule whereas in triglyceride form, three fatty acids are esterified to a glycerol backbone.

Don’t worry about what have just been said – in simple terms, fish oil in triglyceride forms are easier to be absorbed.

Natural fish oil is in the triglyceride form. However, in order to concentrate the amount of EPA and DHA, the oil is converted to ethyl ester form (this process is called molecular distillation). This is how we are able to get more concentrated omega-3 content in fish oil capsule than found naturally in fish.

It is possible to convert ethyl esters back to triglycerides – but the process is costly and adds to the cost of manufacturing. This is why most fish oil brands in Malaysia are in ethyl ester form.

Toxins or contaminants consideration

Fatty fish often contains considerable amount of toxins and can cause serious damage to human body. Some of these toxins include: heavy metals, PCBs (polychlorinated biphenyls) and dioxins.

But fish oil brands in Malaysia are normally molecularly distilled in order to concentrate the amount of omega-3 as well as to remove the toxins mentioned above.

In other words, look for fish oil that are molecularly distilled.

Interesting finding:

There is actually an International Fish Oil Standards Program. They actually grade fish oil by batch using a 5-star ranking system. Most brands available in Malaysia are not graded btw, but you could find Barlean’s and Pristin up there if you are interested.

Other considerations

Other factors you might want to consider:

  1. Liquid or capsule – liquid fish oil is normally better absorbed than capsule, but trust me capsule form is much easier to be consumed.
  2. Size of the capsule – depending on the dose you need, some people might need to take a few capsules a day. And fish oil capsules are normally quite big in size
  3. odourless vs normal fish oil – if you get fishy burps, you might want to consider getting an odourless fish oil
  4. Fish oil only or combination – There are a few combination products out there, krill + fish oil, evening primrose + fish oil etc. Generally I recommend getting just fish oil on its own and if the others separately if needed.

What about wild Alaskan salmon fish oil or salmon oil? Are they any different?

Like mentioned above, salmon is a type of fish that is very rich in omega-3. Besides omega-3, salmon oil is also rich in other nutrients such as vitamin B, selenium, and astaxanthin.

Having said that, salmon is also a more expensive fish to be consumed.

My person opinion? In the end, it still comes down to the omega-3 content – ultimately that’s what matters. Another important factor to consider is this: the source of salmon oil.

There are two types of salmon oil, wild caught salmon oil or sea-farmed salmon oil. Generally speaking wild caught salmon are definitely more nutritious than farm-fed salmon.

In the wild, salmon eat smaller fish that are high in EPA and DHA — the beneficial, long-chain omega-3 fatty acids, whereas farm-raised salmon eat high-protein food pellets.

difference in nutritional value of sea-farmed salmon vs wild caught salmon


Another factor to consider is the amount of contaminants. Farm-raised salmon are found to have higher levels of contaminants compared to wild caught salmon.

Bottom line: If you want to get a salmon oil supplement, definitely get a brand that says wild and/or alaskan fish oil.

(image source)

Krill oil vs Fish oil which is better?

Krill oil is a supplement that is rapidly gaining popularity in Malaysia as an alternative to fish oil.

As implied by the name, it’s oil extracted from krill , which is a type of small crustacean consumed by whales, penguins and other sea creatures.

Thanks to clever marketing, krill oil is often perceived as a more superior omega-3 supplement to fish oil. But is it really so?

Omega-3 in krill oil can be absorbed more easily by human

Though inconclusive, this study found that there seems to be a difference in bioavailability of EPA and DHA after intake of Krill Oil and Fish Oil (krill oil being more superior).

The theory goes like this:

Omega-3s in krill oil are primarily in phospholipid form, whereas omega-3s in fish oil are in triglyceride form (and ethyl ester form if it’s a fish oil supplement).

And omega-3 in phospholipid form gets absorbed better when ingested.

Do note that this claim has not been proven – more studies are needed to prove this.

Related reading: 5 Supplements to help lower your cholesterol

Krill oil contains an extra antioxidant: Astaxanthin


Astaxanthin is the pink-reddish carotenoid pigment that causes the pink or red colour in salmon, trout, lobsters, shrimp and other seafood.

It is one of the best antioxidants you can get from the nature. Some of the benefits of astaxanthin are as follow:

  1. Strong antioxidant – as found in this study, compared to other carotenoids, astaxanthin displayed the highest antioxidant activity against free radicals
  2. Amazing supplement for skin – not only an antioxidant, astaxanthin also displays anti-inflammatory properties. This makes it an effective supplement to help improve skin health and slow down the ageing process
  3. Anti-cancer – perhaps the most valuable effect of astaxanthin. As per this study published in year 2005, astaxanthin was shown to reduce the growth of breast cancer cell. Astaxanthin has also shown some promising results in reducing oral cancerliver cancercolorectal cancerlung cancer and prostate cancer.
  4. Reduce blood pressure – this 2006 study suggested that use of astaxanthin may help to reduce blood pressure
  5. Helps with joint pain/arthritis – As per this article published in year 2013, astaxanthin helps to reduce inflammation associated with arthritic pain.
  6. Male fertility – Astaxanthin may help to improve male fertility according to a study done in year 2005

Take-home point: More evidence is needed to prove that krill oil gets absorbed more easily compared to fish oil, but the additional benefit of astaxanthin is definitely worth a try. My suggestion is that if you don’t mind about the extra cost, definitely go for krill oil

Cod liver oil: Is it better than fish oil?

Cod liver oil used to be a very popular supplement in Malaysia. I can still vaguely recall those days when mum gave me a spoonful of this white colour liquid everyday.

Cod liver oil is in fact another type of fish oil, derived from the liver of Atlantic Cod. Like fish oil, it is very rich in omega-3 fatty acids and has been used extensively to help reduce inflammation and as omega-3 supplements.

But unlike fish oil, as it is extracted from liver, it contains a lot of fat-soluble vitamins that normally get stored in the liver – Vitamin A and D.

I can’t quite remember why I was given the cod liver oil supplement when I was little, but I think cod liver oil was originally marketed to help prevent Rickets. Rickets is a condition that results in weak bones in children due to lack of vitamin D.

In other words, I was given cod liver oil as a vitamin D supplement.

Now, back to the question: is cod liver oil better than fish oil?

My short answer is I no longer recommend cod liver oil over fish oil anymore, eventhough it has the additional vitamin A and D.

The reason being:

  1. Cod liver Oil supplements in Malaysia often don’t specify the amount of omega-3 in each capsule. The amount of vitamin A and D is shown on the label though.
  2. Most of us Malaysians get plenty of sunlight exposure already, so vitamin D supplementation might not be neccessary for most people.
  3. Too much vitamin A and D could be harmful. Unlike vitamin B and C, Vitamin A and D are oil soluble and can accumulate in the body if too much was consumed.

Flaxseed oil: the omega-3 of choice for vegetarians

All the supplements mentioned above are all of animal origin and are mainly omega-3 in the form of EPA and DHA.

For vegetarians, they can get their omega-3s in the form of ALA. ALA is the precursor of EPA and DHA.

After being absorbed, ALA get converted to EPA and DHA in the body – but the conversion rate is extremely low (1%), hence why EPA and DHA are the preferred omega-3.

ALA can normally be obtained from nuts and seeds. One of the most common source of ALA is flaxseed oil.

Flaxseed oil is also known as linseed oil, and is made from the oil released by grinding and pressing the flaxseeds.

Is flaxseed oil better than fish oil or krill oil?

Definitely no.

ALA is converted poorly to EPA and DHA in our bodies. That means you will need to take a lot more flaxseed oil to get the benefit you get from fish oil and krill oil. (about six capsules of flaxseed oil to get the omega-3 found in 1 fish oil capsule)

The other concern is the high omega-6 content in flaxseed oil. Omega-3 is anti-inflammatory but omega-6 is pro-inflammatory, which means the anti-inflammatory effect of omega-3 will be discounted when omega-6 is also present.

(please note: I’m not saying we should avoid omega-6 altogether, but we are getting more than enough omega-6 from our daily diet already)

Flaxseed oil does offer an additional benefit over fish oil though- it doesn’t cause fishy burps and is therefore generally better tolerated than fish oil. If you can’t stand the fishy taste of fish oil, and don’t want to spend too much on krill oil, flaxseed oil might be a suitable alternative. After all, a bit of omega-3 is still better than none at all.

I hope this post answers some of the questions you might have over fish oil, krill oil, and flaxseed oil. Leave me a comment if you have any queries and if you think there is anything i missed out in this post!

Related reading: Everything you need to know about blood pressure