Krill Oil Versus Fish Oil

    From time to time our readers/customers ask about krill oil. Often this results from the promotion of this by Dr Mercola. Here is the latest one...

    Michael comments:

    Dr. Mercola's site just published opinion on krill vs. fish oil. Would love you to take a look and explain your opinion--there is some crazy responses (but i believe from most who think they are experts')

    Thx Mike

    p.s.--one did say that Byron Richards stated there are only 6 small studies on krill--but there was no response to that post--not surprising.

    Warren responds:

    Yes, Michael there has been very few studies on krill oil to date, and there is no evidence supporting the assertion that phospholipids are more bio-available than either the triglyceride or ethyl ester forms of fish oil.
    Dr Mercola does make some pretty wild claims such as krill is 200 times less prone to oxidation than fish oil…primarily because of the presence of the astaxanthin, and of course the constant references to the improved bio-availability.

    I have a lot of respect for Dr Mercola but I think that some of the references made in this article claiming the virtues of krill are over the top and his remarks putting all fish oils into the same basket are downright unfair. There are certainly some bad fish oils out there, but, there is also a lot of very high quality ones…ours included.

    Interestingly, they do not publish actual lab data on the purity of the krill oil or data on the oxidation either.

    I have posted below a copy of a blog article that I did some time ago relating to Dr Mercola’s krill oil. I have not checked whether the pricing is still the same, but I am sure that overall financial comparison will still be valid.
    It started off with a posting on the blog:

    Blog posted in August 2009

    Question: from Marena

    Please, enlighten me. What about the Krill oil that Dr Mercola sells? Please, tell me your truth. Many thanks.

    Answer: from Warren

    Krill oil is really an interesting product in that it is more hype than substance. A few years ago we were offered krill oil but decided to stay with our fish oil.

    The reason being that it just didn’t make sense to change, and although that was some years ago I have seen nothing to change our position on this.

    There are a number of things that don’t 'sit right' with me about krill oil.

    1. The marketers of krill oil claim that it is more sustainable than fish oil. I really am at a loss to understand their reasoning on this. At the moment fish oil is not a drain on fish resources simply because the fish are not caught just for their oil. They are caught for their flesh for human consumption. A by-product is the fish oil of which 90% is used for industrial and agricultural purposes. Less than 10% is used for fish oil supplements. So, the use of fish oil for supplements has zero impact on the sustainability of fish.

    On the other hand the krill is caught solely for the purpose of converting into oil for supplements. So, for each ton of krill that is caught there is one less ton of feed available for whales and other fish that depend upon it. The entire marine ecosystem starts with the krill. By reducing the amount of krill available in the oceans may have other long term implications. Therefore I would not personally use it.

    2. The other argument used by marketers of krill oil is that krill has less contamination. This is a valid argument when comparing with some fish. However, it is possible to get the same level of purity with fish oil as with krill if it is handled and processed correctly so it you are using a good brand of fish oil this is not an issue unless it is not molecularly distilled. If it is not distilled then you have to be a lot more careful as the type and source of the fish is very important.
    For example, the fresh New Zealand hoki that we use is totally different to most of the fish in the Northern Hemisphere which does have high levels of contaminants…but our NZ hoki is free of such contaminants. Have a look at our Buyers Guide for more info.

    3. A big thing is made of the presence of astaxanthin because it is an antioxidant. No argument there but it is nothing to make a big deal about. For example, the typical level is only 0.3mgs per soft gel or 0.6mgs per daily dose. (That is what is in Dr Mercola's product). Interestingly, the level of astaxanthin in krill is quite low. Most of it is added after the ‘event’ to bring the levels up to that stated on the labels. They use the same astaxanthin in krill oil as we use in our DHA Plus and QH Premium CoQ10 Omega 3 Fish Oils.

    All our fish oils contain mixed tocopherols and anti-oxidants and rosemary extract as well.

    4. Krill oil will generally not 'repeat' on you like most fish oils. However, quality fish oil will not repeat either. The problem is that many do because of the way in which the fish is handled where the 'crude' oil is substandard. We don’t have that problem because we control the entire process.

    And lastly there is the question of Omega 3 content and price.

    A bottle of Dr Mercola’s krill oil has 60 caplets for $24.95 which contains:
    EPA – 2,700mgs
    DHA – 1,500mgs

    In contrast a bottle of Xtendlife’s Omega-3 DHA fish oil which has 60 soft gels contains:
    EPA – 7,200mgs. That is just under 3 times as much.
    DHA – 16,800mgs. That is more than 11 times as much.

    Plus the Mercola product costs 45% more!

    I hope that this answers your question Manena

    14 Responses

    Every time this Krill oil controversy pops up I add a rider to the comments – including on Mercola’s site. Simply – life-conservation here on Earth.

    I concur with John Evans – and would ask that all readers consider just how efficient we humans are at raping the food sources of the planet. Krill are the basis of all life-forms in the ocean, not just baleen whales but of smaller fish, which in turn become the food source of species further up the food chain – including Hoki.

    The vast resource of Atlantic Salmon off the Grand Banks of Canada and the USA is now lost – 1000 years of fishing destroyed in less than 60 years by the hugely efficient methods employed since 1950. Likewise, in many areas around the world fish stocks are declining rapidly and of course once the process is begun it accelerates.

    Let us no destroy Krill with our usual efficiency. If no one will buy it (and it is a processed protein source), no one will fish for it.

    I do like the irony that Nature exhibits – Global Warming in historical terms (geologic evidence) to quite sudden Ice Ages – induced over decades rather than millenia. If this should happen, it will suck to be Japanese but be great to be a whale.

    Murray October 29 2010

    Hello! FELESIA, I Used Krill Doctor professional Brand Krill Oil, No smell or bad taste. Has been taking one capsule at bedtime. Cholesteral dropped 1.6 points in three months. Thanks to Krill Doctor Professional.

    tammy23 August 19 2011

    I USED KRILL ONE EVERY DAY AND I RASH ON MY ARM.I don’t know if its not good for me .I CHANGE FROM FISH OIL.

    neezam October 06 2012

    To John Evans:

    Thanks John for your feedback. The caplique was going to be the greatest thing since sliced bread when it came out quite a few years ago.  It was developed by Capsugel and was considered to have various benefits over and above soft gels. We considered it and looked into purchasing the equipment to make them, but after extensive research found that there were not benefits at all which could be quantified and supported with good scienceso, we stayed with soft gels.

    Warren Matthews October 29 2010

    Awesome information Warren, thank you! My husband saw the Dr. Mercola informercial and bought the hype. He tells me I am detroying the universe with my fish oil…grrr. I will definitely share this blog with him tonight!!

    Tiff G October 21 2010

    I have to say I’ve used both Dr Mercola’s Krill oil and Xtend-Life Omega 3 /QH Ultra.  I continue to stick with the Xtend-Life, but I will also support that Dr Mercola is NOT a snake oil salesman as stated here by another opinion.  Dr Mercola is a well educated person who looks to bring natural products to his clients.  I support Dr Mercola and use some of his other products, I just choose Xtend-Life’s fish oil because i like the ingredients better.   But I think it’s unfair to call Dr Mercola a snake oil salesmen when he brings loads of great articles with document research behind them to the consumer.  And he always tells you to do your own homework and in this case I chose Xtend Life.

    Michael March 09 2011

    There are two Canadians companies involved with krill, 1Neptune makes the capsules 2 Acasti is studying what effect krill could have for cardiovascular diseses.

    Guy January 20 2013


    FELESIA March 25 2011

    Hello Neezam

    If you developed a rash from using Krill you may have an allergy to the Krill. Although there hasn’t been a direct link between Krill and an allergy to shrimp, you should avoid taking Krill oil if you have a shrimp allergy.

    It is good to know that you can take Fish Oil without a rash reaction.

    Xtend-Life Expert October 09 2012

    Mercola is a snake oil salesman, and anything he promotes is extremely suspect and best to avoid. Notice I didn’t use "Dr." before his name.

    wyndham wales October 22 2010


    Not sure where you get your information but you are being mislead on several issues.
    1. There are studies showing that Phospholipids are a better delivery system email me and I will send them to you.
    2. I have been working with krill oil for almost 9 years and can tell you that in that time I have never had anyone taking krill oil tell me they "burp" (a common thing w/fish oil.
    3. Krill sustainability is far better than fish oil industry (again I will send you info if you would like. Krill is the most regulated feed that comes out of the ocean, only 1% of all krill fished is used for supplements. So if you want to say anything about krill have your facts straight!
    4. Even though there are few studies on krill oil and many on fish oil not everyone can take fish oil. I keep telling people do not take krill for their Omega’s take krill for Phospholipids & Astaxanthin.
    5. Astaxanthin has many studies and you can look them up.
    6. I challenge anyone who wants to take krill for 6 months to a year to show me they cannot see the difference in their lipid profile.

    Most of the clinicals for fish oil are on very large amounts 5-6mg a day or more. Krill is not fish oil will never be fish oil and works different. But I can show you beyond a doubt that krill fishing is the most sustainable fishing in the world. 

    Mickey Schuett
    Azantis, Inc.

    Mickey November 11 2010

    I’m confused on how many Krill Oil softgels I should take a day as compared to regular Fish Oil softgels (1000mg). The Krill Oil EPA and DHA amounts seem so low compared to the fish oil but I’ve seen that only one Krill oil a day is needed. Does anyone know if that is correct?

    Xtend-Life Expert January 12 2013

    Thank you so much! There is so much false and contradicting information out there. I am grateful I am able to access clear and documentable information from your site.

    Janine October 23 2010

    Hi Mickey,
    I appreciate your comments. Here are mine.

    1. Are phospholipids more bio-available? There is certainly a lot of controversy about this, just as there is between ethyl esters and triglycerides. I have not seen anything conclusive so I would welcome copies of the studies that prove this. Bear in mind that the dose rates for krill oil are significantly lower, so in order for this to be a valid argument then the difference would have to be remarkable. Krill oil is much more expensive. There is very little upside in getting improved bio-availability if you are still only taking a fraction of the amount which you are getting with a normal fish oil dose.
    2. Agreedrepeating with fish oil is quite common but not if it is fresh.
    3. Sustainability. I disagree with you here. The reality is that there is a LOT less krill about now than what there was 20 years ago. I live in the South Island of New Zealand at around 43 degrees south. In the early 80’s I had a commercial fishing operation and in those days we would see great masses of krill over many areas of the ocean. I still spend a lot of time on the ocean and over the last few years the krill has vanished locally. Just the other day I was talking to a commercial fisherman and he was saying the same thing. Even if only a small percentage of the krill being caught it being used in supplements it is certainly a factor in driving the harvesting of it as the krill which is used for supplements is much more valuable than using it for agricultural purposes. The reality is that it is whale food. Even though there may still be more food in the cupboard for the whales they may find it harder to get. They dont have an alternative.
    4. I agree that astaxanthin is an excellent nutrient. That is why we add it to our Premium and Ultra versions of our Omega 3 fish oils. Although marketers of krill make a big thing about the astaxanthin in krill the amount naturally present is actually quite low. Most manufacturers of krill oil add astaxanthin to their product. I know this as the supplier of our astaxanthin is the same who supplies a number of those manufacturers. However, astaxanthin is not a practical substitute for a good daily dose of Omega 3 with DHA and EPA.
    5. We have a number of studies on our website about astaxanthin. but, we are always interested in reviewing more.
    6. What specific changes in their lipid profile would you expect and how can you be certain that they would not get as good a result, or better with fish oil?

    Sorry, but I cant comment on the last point as I could not get the link to work or find anything related to it on google. I should mention that the Hoki fishery in New Zealand is considered to be one of the best managed sustainable fisheries in the world. A view supported by the Marine Stewardship Council.

    Warren Matthews November 15 2010

    Leave a comment (all fields required)