The Fish Oil Showdown

Updated on 14th Sept 2016 Here I have selected a number of popular omega-3 supplements to compare the quality of each one. I will look at the dosages of...

Updated on 14th Sept 2016

Here I have selected a number of popular omega-3 supplements to compare the quality of each one. I will look at the dosages of omega-3, vitamin content, processing methods, testing and chemical form of the omega-3s. Usually I try and keep all posts unbias by avoiding naming brands, but there was quite a bit of demand by readers on a post explaining the different processing methods of cod liver oil products for me to name brands, so I decided to do that in this post. I have only compared 7 brands/products, so if the fish oil brand you use isn’t shown in this post, you still should be able to see what information is important in choosing a fish oil product.

It is quite a long post, so to help navigate to brands of particular interest, or if you just want to look at a summary of the whole post, you can use the content navigator on the right. Let the fish oil showdown begin!




PurePharma are a well recognised name amongst athletes, especially those in the cross fit community. They produce a fish oil aptly named O3, and pride themselves on the quality and potency of this product. The specifications of which can be seen below:

  • PurePharma-O3Price per serving (based on RRP): £0.66
  • Fatty acid format: Triglyceride
  • DHA: 500mg per serving
  • EPA: 1250mg per serving
  • Vitamin A: 0
  • Vitamin D3: 0
  • Vitamin E: small amounts added for stabilising.
  • Fish sourced from: South pacific ocean
  • 3rd party testing? – yes, and results made public. You can view the IFOS test results here.
  • Extraction: Not disclosed.

Omega-3 content – O3 is solely an omega-3 supplement, and unlike other fish oils/ cod liver oils, doesn’t include any vitamin A or vitamin D. Instead, O3’s omega-3 content is much much higher than similar products, and this ensures that you are getting an effective dosage of these important fats – ideal for someone who has quite an intense training schedule. If you are not an exercise fanatic, your need for EPA and DHA will be lower than athletes, but this product can still be for you, just lower the dosage (which will also make it a cheaper per dose).

In addition to providing more EPA and DHA than other products, these fatty acids are in a triglyceride form, which research has shown to be much more absorbable than the ethyl-ester form which is more commonly used in fish oil product due to its chemical stability.

Processing – Undisclosed, but as there is 3rd party testing, this is of no concern to me.

Testing – The fact that the extraction method is undisclosed is not of much concern with this product. It is nice to know how the oil is isolated, but only to give a clear picture of the quality of the oil, and the 3rd party test results clear up any concern. The 3rd party testing provides any customer with reassurance of the quality and potency of the product.

Sourcing – The sardines and anchovies used in this product are sustainably sourced from clean waters in the south pacific ocean. This is an added environmental bonus of taking PurePharma’s O3.

Special features – PurePharma O3 also is is contained in dark capsules, which you rarely see in in a fish oil product. The purpose of this is to protect the contents from light, which can cause oxidative damage. Its a nice touch, but as the bottle is dark, I don’t think the capsules really would be exposed to much light. Still, it shows that there is attention to detail.



Carlson Labs

Carlson labs have enjoyed a long history of producing cod liver oil products, and produce a number of varieties from capsules, to liquids, and with varying amounts of vitamins/ omega-3s. For this comparison, I have used their standard cod liver oil, which will give a good picture of how the company works/ quality of the products. You can see the specifications of this product below:

  • carlsonPrice per serving (estimates based UK retailers): ~£0.50
  • Fatty acid format: Triglyceride
  • DHA: 500mg per serving
  • EPA: 400mg per serving
  • Vitamin A 850IU per serving
  • Vitamin D3: 400IU per serving
  • Vitamin E: 10IU per serving (as mixed tocopherols)
  • Some are naturally occurring vitamin A and D, but levels are topped up with D3 and synthetic vitamin A (retinyl palmitate).
  • Fish sourced from: Norway
  • 3rd party testing? – yes, and results made public. You can view the IFOS results here.
  • Extraction: Steam/ molecularly distilled

Omega-3 content – The EPA in Carlson Labs cod liver oil is much lower than that of PurePharma’s O3 by 850mg, which is a significant drop, but how significant it is to you depends on your diet and personal EPA requirements. Carlson Labs cod liver oil will provide anyone with a valuable dosage of EPA and DHA, and as these fats are in the triglyceride form, you know they are easily absorbable.

Processing – Carlson Labs are the only company to disclose how they extract the oil – through molecular distillation. This process is quite common, and when done correctly is great for removing toxins. The 3rd party testing of this product demonstrates the care taken in the processing.

Testing – The 3rd party testing clears up any concern about the quality of Carlson Labs cod liver oil. The low levels of toxic chemicals, and consistent omega-3 content provides all users with reassurance of the quality.

Vitamins – Carlson Labs cod liver oil is also a source of vitamins A and D. A large proportion of the naturally occurring vitamin A and D has been removed during extraction of the oil, but levels are topped up with vitamin D3 and vitamin A palmatate. Both these forms are biologically active (as opposed to vitamin D2 for example), but the various benefits of the metabolites of these vitamins will be lost.

The vitamin A content per serving is approximately 17% of your RDA of vitamin A, whereas the vitamin D content is about 100% your RDA. You might think that the vitamin A content is quite low, but it is important to keep vitamin A supplementation to a minimum, as in large amounts it is toxic. As an adult your maximum tolerable level of vitamin A is 10,000 IU. Carlson Labs will provide 8.5% of your total tolerable amount of vitamin A, which is of no concern as long as you are not taking any more supplements which contain vitamin A. There is no reason to be consuming more than the suggested serving anyway, as the dosages of EPA, DHA, vitamin A and vitamin D in each serving are ideal for most people.




Healthspan are a an online retailer of health products with a focus on affordability. Their range of products is extensive, and they have a variety of cod liver oil products that offers a lot of choice to customers. For this post I’ll use their generic cod liver oil as I feel it is a good representation of the production and quality of the oils Healthspan produce, the specifications can be seen below:

  • healthspanCost per serving: £0.05 (based on RRP)
  • Fatty acid format: Ethyl-ester
  • DHA: 105mg per serving
  • EPA: 120mg per serving
  • Vitamin A 1333IU per serving
  • Vitamin D: 200IU per serving
  • Vitamin E: 0
  • Fish sourced from: Iceland
  • 3rd party testing – No, only in-house testing, and no results available publically.
  • Extraction: No information
  • Vitamins: “vitamins in our cod liver oil are naturally occurring” (I suspect this isn’t quite true as they have very high and round numbers).

omega-3 content – The first thing you probably notice about this cod liver oil is the cost per serving is 90% less than the previous 2 cod liver oils, but before you think this is a fantastic bargain, there is good reason for this. The DHA and EPA content of this oil is 21% and 15% respectively of Carlsons Labs cod liver oil and even less than that of PurePharma’s O3. This shows how dilute Healthspans cod liver oil is in comparison to the previous 2, which allows the product to be very cheap. This is not a bad thing for everyone though. If you regularly eat foods high in omega-3 fatty acids (such as fish, nuts and seeds), you can use Healthspans cod liver oil to ‘top-up’ your EPA and DHA levels at very little expense. However, if you don’t eat much of these foods, you will need to take 5+ capsules a day to come close to a good amount of these fats (which can have problems in itself, which I’ll get to). In addition to this low amount of EPA and DHA, these fatty acids are in the ethyl-ester form, which means their absorption in the digestive system will be poor compared to PurePharma’s O3 and Carlson’s Labs cod liver oil.

Testing – The lack of publically available testing is a concern for me. The health supplement industry is largely unregulated, and although guidelines are in place, there is very little enforcement. I have no idea how accurate the nutritional information on the label is or the level of oxidation of the fats. I have been told that the levels of mercury are 0.005mg/kg, which is much lower than the European pharmacopoeia reference which is 0.1mg/kg. This offers some confidence, but there is no other information about important factors, such as amount of fats which are oxidized.

Processing – Without the 3rd party testing available, I would like to know h0w the oil is extracted, so I can judge how damaging it is for the omega-3 fats. When I asked Healthspan about the purification process I was told they use a “patented purification process” which uses “exclusive purification technology“. This is a very vague, and uses fancy words which means nothing to anyone. What is the patented purification process? What is the purification technology that you suggest only you have access too? I get no concrete answers. This leads me to 3 possible reasons as to why they are being vague. The representative may not know the answer, the representative is not allowed to tell me (although they could have said they can’t tell me) or, more worryingly, they use a rather harsh process which damages the omega-3 fats, and don’t want to tell me. Either way, the processing is a mystery, and without the 3rd party testing, what the capsules contain is also a mystery.

Vitamins – When I asked if the vitamins A and D were the vitamins naturally found in cod liver oil, I was told “vitamins in our cod liver oil are naturally occurring“. If this is true, how have they got such consistent and round numbers? (Vitamin A covers 50% RDA and Vitamin D covers the RDA 100%) They must have added both vitamin A and D from some other source, at least to top up the levels of these vitamins in the same way Carlson Labs have. There is also no mention if the vitamin D is D3 or D2 (which is important), and the high levels of vitamin A is worrying. If you take 5 capsules a day of Healthspan’s cod liver oil (which you will need to do to meet the a good dosage of EPA and DHA), you would be consuming 6665IU of vitamin A. This is getting worryingly close to the maximum tolerable value of 10,000IU before you have even eaten any food!



Natures Best

Natures best, as their name suggests, strive to provide customers with the best. They take pride in the fact that their products are manufactured in the UK (not in China), and provide honest and clear labelling of their products. They have a vast range of products, including a total of nine fish oil products. For this comparison I have chosen their standard cod liver oil, as I feel this gives a good representation of the processing/ quality/ standards the company will maintain across all their products.

  • natures-bestCost per serving: £0.06
  • Fatty acid format: Ethyl-ester
  • DHA: 107mg per serving
  • EPA: 144mg per serving
  • Vitamin A: 2666IU per serving
  • Vitamin D: 400IU per serving
  • Vitamin E: 10mg
  • Fish sourced from: Refused to specify
  • 3rd party testing – No, only in-house testing, and no results available publically.
  • Extraction: Molecular distillation
  • Vitamins: Some naturally occurring vitamin A, E and D, but levels are topped up with D3, dl-alpha tocopherol (Vitamin E) and vitamin A (retinyl palmitate).

Omega-3 content – The omega-3 content of Natures Best cod liver oil is very comparable to that of Healthspans. Quite low, but useful to use as a ‘top-up’ of omega-3s to your diet. As they are in ethyl-ester form though, your absorption will be poor compared to PurePharma’s O3 and Carlson’s Labs cod liver oil.

Testing – They only have in-house testing which is not made public. I have been told that their in-house tests “include screening for a variety of contaminants such as aflatoxins, heavy metals, antibiotics, PCBs, dioxins, PAHs, irradiated ingredients and pesticides”. This is great to hear, but if their screening is so thorough, I don’t see why the results are not made public. They also don’t seem to test for oxidation of the fats which is a huge concern for me, because an oxidized omega-3 is nutritionally useless.

Vitamins – Natures Best did tell me that the processing of the cod liver oil does deplete the vitamins in the oil, and so they are topped up with synthetic vitamin A palmitate and vitamin D3. This much they are open with, which is refreshing after my concern with Healthspan’s vague response to this question. I am very concerned with the amount of vitamin A which is in this product though. The levels are double that of Healthspan’s cod liver oil, which means that if you take 5 capsules you will be consuming over 13,000IU of vitamin A – well over the toxic dosage.

Sourcing – Up until this product, I was impressed with all the sourcing of the fish, and almost didn’t include it as a criteria. However, Natures Best actually refused to give me any information on the sourcing of there cod, which is odd, as all other companies told me where their fish was sourced (sometimes even before I asked!). The reason Natures Best gave me for not telling me their source was due to human activity, no ocean is completely free from pollutants”. Riiiight, so why can’t you tell me where they are sourced from? I can only think of 2 reasons why they didn’t give me an answer. The first is that perhaps they source from different seas and oceans, but I don’t see why they couldn’t say that. The second reason, which I suspect is a little more likely to be true, is that they are embarrassed by their source, because it is an inferior in some way. I’m thinking somewhere like China. Now I don’t know this, it’s just a guess, but I would like to know where my supplements come from, and every company I’ve spoken to has told me.

Company Ethos – Before I move away from Natures Best, I’d like to have another look at the company ethos – it seems a bit off to me. On their ‘About’ page they are quick to condemn manufacturing from China due to the poor quality, yet they are unable to disclose their source of cod liver oil, and don’t mention anything about how bad sourcing from China is. If the source of products is so important to Natures Best, and take pride in the fact that they manufacture their products in the UK, why won’t they disclose the source of raw materials? It smells fishy to me (no pun intended).



Green Pastures

Green Pastures are a company which extract oil in a very unique way. They use an “ancient extraction method” for their oils, and with the case of their cod liver oil, they use salt water fermentation. Their primary focus in producing oils in a natural way, which is very different from other oil producers. Green Pastures offer a variety of cod liver oils, but for this example I have used their fermented cod liver oil, as I feel it is a good representation of the companies processing/ quality standards/ ethos. You can see the specifications for their cod liver oil below.

  • green-pasturesCost per serving (based on UK retailers): £0.50
  • Fatty acid format: Triglyceride (with small amounts of free fatty acids)
  • DHA: 58 – 84mg/g
  • EPA: 120 – 157mg/g
  • Vitamin A 625 – 689IU/ g retinol (+ approx 600 mg/g as a palmate)
  • Vitamin D: 0 – 329IU/g
  • Vitamin E: 0
  • Quinone – 5.65 – 17.06mg/g
  • Fish sourced from: Arctic waters
  • Extraction: Sea water fermentation
  • 3rd party testing – Yes, the most extensive testing for any cod liver oil ever. They have used at least 3 different independent labs to test their product, and you can find more about this here, and here.
  • Vitamins: All are naturally occurring with metabolites.

Omega-3 content – As this is a natural product, the content of active ingredients is not standardised, and can vary depending on various factors. This means that EPA and DHA levels fall between a range of values, rather than being a specific value. The amount of EPA and DHA that Green Pastures provides is not very high, especially compared to PurePharma or Carlson Labs who seem to concentrate the oil. However, as the fats are all triglycerides they are much more absorbable than the ethyl esters, which means that this is still a valuable source of both EPA and DHA.

Testing – Green Pastures have had their products tested by Eurofins and Midwest Laboratories. Some of their results are self published, but others are the original documentation, which means that the results cannot be tampered with.

Sourcing – Green Pastures cod liver oil is sourced from waters around the Arctic. These waters are renowned for being the lowest in pollutants, which is important for this product seeing as it undergoes such little processing, so pollutants will not necessarily be removed if they were present. Fortunately, as you can see from the test results, pollutants are extremely low, and can be considered insignificant.

Vitamins – The vitamin content in this product really can vary, which is a bit annoying, but that’s what you get if you have a completely natural product. The good news is that this cod liver oil will contain vitamin metabolites. These metabolites can be thought of as the vitamins in various forms of creation, and are always found with vitamins in nature. When you eat an orange for example, you consume vitamin C and lots of vitamin C metabolites. Most cod liver oil/ fish oil processing will remove these metabolites, and add only the vitamins back into the oil, but not Green Pastures – this oil contains it all. Vitamin metabolites improve the absorption of the complete vitamin, and have a number of additional benefits themselves.

Additional nutrients – Using salt water fermentation has the added advantage of producing a number of additional nutrients and co-factors. Aside from the naturally occurring omega-3 and vitamins, fermented cod liver oil contains quinones (a group of nutrients which Coq10/ ubiquinol belong to), and other co-factors in various quantities. This is a clear benefit over other similar products.

Processing – Using salt water fermentation really is the safest way to produce a cod liver oil. It uses no heat, chemicals or pressure, so you do get a very natural product. It’s so natural, you can think of it more like a food than a supplement.

Special feature – In keeping with the natural theme of this product, the capsules are made with beeswax, not gelatin. This has no significant health benefit, but can be considered to be more environmentally friendly.

N.B You may have noticed that the vitamin A & D levels vary for this product quite a lot compared to others. This is for 2 reasons. The first is that Green Pastures do not standardise their product by adding synthetic vitamins – it is as nature provides, which is why there is some variation. The second is that there are many many ways of testing for vitamins (particularly vitamin D). Some only test for one form (e.g D3), some can distinguish between metabolites, and some cannot. The reality is that tests for vitamin D are extremely variable and complex, and depending on the source, you will find different values, hence the variation. These values are from a recent report from the WAPF which you can read here.

In the interest of full disclosure, we do sell green pastures cod liver oil in our webstore, but I’m not saying that this cod liver is great because we sell it, we sell it because it is great.



Seven Seas

Seven Seas is a well established brand of cod liver oil, and they are often found in most high street health stores or chemists. They have enjoyed a reputation for producing affordable cod liver oil, and are a well recognised brand of cod liver oil in the UK. They have a variety of different cod liver oil products, but for this example I have used their standard cod liver oil ‘One-a-day’ , as I believe it gives a clear representation of the company.

  • seven-seasCost per serving: £0.08
  • Fatty acid format: Mix of triglyceride and ethyl-ester
  • EPA + DHA: 85mg per serving
  • Vitamin A: 0
  • Vitamin D: 100IU per serving
  • Vitamin E: trace
  • Fish sourced from:”predominantly from open waters
  • 3rd party testing: Yes, but not made public.
  • Extraction: “unable to divulge the process
  • Vitamins: Most are added after extraction, vitamin D3 is sourced from lanolin (sheep wool)

Omega-3 content – EPA and DHA combined come to a total of 85mg, and no individual amounts are given. It is possible that all of this is either DHA or EPA, or only 1mg is EPA and 84mg is DHA etc. It makes no sense to display these fatty acids like this, unless they are trying to hide the figures of these fats – which they may well be doing. 85mg is a tiny amount of EPA/ DHA, and is a fraction of other products in this post. I was quite cynical of the low amount of EPA and DHA in Natures Best cod liver oil, and Seven Seas cod liver oil is 66% lower than Natures Best!

This is the only product so far which I have seen to contain a blend of both ethyl-ester and triglycerides, although the ratio of this isn’t specified. The way in which cod liver oil is processed requires the fatty acids to be converted into ethyl-ester form before filtration etc, because the fatty acids are much more easier to control (from a chemical point of view) as ethyl-esters than triglyceride. Companies such as PurePharma will convert the fats back into triglycerides, as they are more absorbable. I don’t understand (and Seven Seas haven’t told me) how only some of the ethyl-esters are converted to triglycerides, and some are not.

There is little benefit to consuming one of these capsules a day (as the name suggests you should) unless already eat plenty of nuts, seeds and fish throughout the day and want a ‘top up’.

Testing – Seven Seas have told me that they have 3rd party tests conducted on their products in UKAS accredited labs, but they do not make the results public. When speaking to Seven Seas they are very keen to say that their products are tested for a vast number of toxins and harmful chemicals, but not for fat oxidation, which, as I’ve already said, is very important. Oxidised fats will not benefit the body, so a capsule of oxidised fats is a waste of time and money.

Sourcing – When I asked about sourcing I was told that the cod are sourced from “open waters”, a bit vague, but at least we know it isn’t farmed fish. I would expect that Seven Seas make so much cod liver oil that they have a couple of suppliers, so it’s not really surprising that they don’t specify the origin like other manufacturers do.

Vitamins – The vitamin D is in the form of vitamin D3, which is biologically active in humans – good stuff. Interestingly this cod liver oil contains no vitamin A, which I think is actually a positive thing for this product. The lack of vitamin A allows you to consume more than 1 capsule a day without worrying about vitamin A toxicity.



Holland & Barrett

Holland & Barrett are the high street name when it comes to health shops, and there is probably one in almost every town in the UK. Holland & Barrett have been unable to provide any more information on this product. So as a potential customer, I can only make quality claims based on the information on their website, which is limited:

  • holland-barretCost per serving: £0.09 (based on RRP)
  • Fatty acid format: unknown (suspect ethyl-ester)
  • DHA: undisclosed
  • EPA: undisclosed
  • Vitamin A 2664IU per serving
  • Vitamin D: 200IU per serving
  • Vitamin E: 0
  • Fish sourced from: unknown
  • 3rd party testing – unknown, and nothing made public
  • Extraction: No information
  • Vitamins: Most are added after extraction.

Omega-3 content – On the label the total omega-3 content is quoted at 210mg. They do not not specify how much is EPA, DHA or other omega-3 fatty acids. If we look again at Seven Seas cod liver oil, EPA+ DHA content is 70% of the total omega-3 content, so it is a fair assumption that approximately 147mg of Holland & Barretts cod liver oil is a combination of EPA and DHA (although we still don’t know how much of each). We can only get an estimated amount of total EPA and DHA, and have no idea how much of either, or what form these omegas-3 fats are in (although I suspect they are ethyl-esters). To me, it looks like this brand is preying on those who are not informed, and want to increase omega-3 fat intake, but don’t understand much about it.

Testing – I heard nothing back about testing of their products, but there is no mention of testing on their page. I have no idea if this company even complies to EU standards for cod liver oil, or even if it is cod liver oil in these capsules for that matter.

Sourcing – No idea…

Processing – No idea…

Vitamins – Holland & Barrett’s cod liver oil is another product which has a very high amount of vitamin A in, which will prevent you from taking additional capsules. I have no idea why this much vitamin A is added or where it is sourced from.



Rosita EVCLO

Rostia EVCLO (extra virgin cod liver oil) is a relatively new player on the cod liver oil scene. Their approach to marketing at the start had questionable ethics, but here we will just look at the products that they produce. They pride themselves on being a small producer of cod liver oil and only use natural methods to extract the oil, which means that they don’t use any chemicals or heat. Its worth noting that EVCLO has a higher recommended dosage than most other manufacturers, which is why their nutrients content (and price) is quite a lot higher than others.

  • rosita-evcloCost per serving: £1.00 (based on RRP)
  • Fatty acid format: Triglyceride
  • DHA: 700mg
  • EPA: 510mg
  • Vitamin A 3000-5000IU per serving
  • Vitamin D: 400-500IU per serving
  • Vitamin E: 3.7-10mg
  • Fish sourced from: Norway
  • 3rd party testing – Yes, you can view them here.
  • Extraction: Cold extraction
  • Vitamins: Naturally occurring (except the vitamin E which is added after for stability).

Omega-3 content – As the oils are extracted in a natural way, the omega-3 content will vary slightly from batch to batch. However, all of these oils will be in the triglyceride from which are absorbed much better than the inferior ethyl ester counter parts which will be present in other cod liver oils.

Testing – Testing is done by independent labs, which they do name, but all the results are uploaded by Rosita. This does pose the risk that Rosita can alter their results, but I feel it is unlikely. Tests by the Norwegian Food Safety Authority have found that some of Rosita’s products contain extremely high levels of toxins, which you can read about here.

Sourcing – All the fish are sourced in Norwegian waters, which are known for being low in pollutants.

Vitamins – Only vitamin E is added to the product. Vitamin A and D are all naturally occurring, and so their absorption should be much better than their synthetic counterparts.

Processing – According to Rosita, when cod livers are exposed to cold temperatures the oil seeps out of the livers. This is then simply filtered and bottled with some vitamin E to maintain stability. There is no heat or chemicals used in this process, and all the vitamins/ omega-3 fats are unaltered and all natural.

Additional information – Rosita and their business partners Corganics have been partaken in a very aggressive slander campaign against their primary competitor (Fermented cod liver oil). the campaign includes (but is not limited to) creating fake Facebook profiles to promote EVCLO over FCLO in many communities, and the owner of Rosita creating a video which suggests Green Pastures source their oil from China. You can read more about this here. This kind of behaviour raises some questions about the ethics of this company.


Dropi Extra Virgin Cod liver oil


Dropi are a small manufacturer of cod liver oil based in Iceland. They are rather unique in that they both catch the fish and extract the themselves, which eliminates the need for extensive transportation of the livers and ensures their quality standards are kept and maintained. They are also able to use fresh fish, because their processing site is in the same village that they ship from! The cod they catch is from the pristine waters of the West Fjords, which is renowned for being extremely low in pollutants. All of this results in an extremely clean, fresh and nutritious cod liver oil, which you can read more about here.

  • Dropi Cod Liver Oil ReviewDropi Price per 5ml serving (based on RRP): £0.80
  • Fatty acid format: Triglyceride
  • DHA: 450mg per serving
  • EPA: 350mg per serving
  • Vitamin A: 725µg
  • Vitamin D3: 4.3µg
  • Vitamin E: small amounts added for stabilising.
  • Fish sourced from: Icelandic waters (West Fjords)
  • 3rd party testing? – yes, but not yet released publicly.
  • Extraction: Cold processed (temperatures below 42oC)

Omega-3 content – The omega-3 content of Dropi will have some natural variation due to the natural processing methods. The content is very good though, and due to their extraction process the oils will be in their naturally occurring triglyceride form. This means that they are absorbed much easier in the body than their ethyl-ester counter parts which some manufacturers use. The content is comparable to similar dosages of similar products.

Processing – The processing conditions that Dropi uses are very simple. As the livers are fresh and naturally low in toxins they require less processing that other brands do, which keeps the product as natural and unaltered as possible. Dropi ensures that temperatures don’t exceed 42oC, which allows the oil to be classed as cold processed. This low temperatures ensures that the oils do not get damaged, and so are absorbed much better.

Testing – Dropi have told me that their products are tested by 3rd parties, but they haven’t made these results public. I have been assured that their tests are currently showing that their vitamin D3 levels are now consistently 10µg per serving. I have no reason to believe otherwise.

Sourcing – The cod used in this product are caught by Dropi in the clean and pure waters around the West Fjords in Iceland. Dropi ensure that their fishing practices are done in a sustainable manner and are in keeping with all sustainable fishing guidelines set out by the Icelandic authorities. With the waters being renowned for being very low in pollutants you can rest assured that their cod liver oil will also be extremely low in pollutants too.

Special features – Dropi maintain the chain of custody of the products from the catching of the fish to the finished product. This ensures that their high standards are maintained, and that their product is the freshest cod liver oil on the market. I know of no other brand that can boast such a fresh product.

In the interest of full disclosure, we do sell Dropi’s extra virgin cod liver oil in our webstore, but I’m not saying that this cod liver is great because we sell it, we sell it because it is great.



Starting with the worst:

  1. Holland & Barrett cod liver oil – Compared to similar quality products, it costs 30% more per serving, has less product information available, and I think some of the available information is misleading. I would not recommend at all.  1-star
  2. Natures Best cod liver oil – I was able to get some information about the toxin content of this product, but other information was not provided. I also find the companies ethos vague and contradictory. There is so much information I still don’t know about this product that I would never recommend it to anyone.  1-star
  3. Healthspan cod liver oil – This cod liver oil is a cheap cod liver oil, but it’s not being sold as anything more than that. It costs very little, and will provide very little, but for some people that will be enough. It has a more favourable amount of vitamin A then the above two do, but its ethyl ester form of fatty acids and lack of testing bring it down a bit. 2-stars
  4. Seven Seas cod liver oil – Here we start to see some triglycerides come into the oil which I feel is important, but it is a blend of triglycerides and ethyl esters which is disappointing. There is no vitamin A, which for me is great because I see cod liver oils as an omega-3 supplements, the vitamins are just a luxury. However, the lack of other information has dragged this down for me, and they seem to rest on their reputation. This product is an affordable way to increase your omega-3 fatty acids, but by no means the best. 2-half-stars
  5. Carlson Labs cod liver oil – Omega-3s in triglycerides and high dosages, 3rd party labs tests and conservative levels of vitamins. This is simply a good product with no frills or fancy add-ons. I would recommend this to anyone who is looking for a high quality and cost effective omega-3 supplement. 4-stars
  6. PurePharma fish oil – This fish oil is highly concentrated with high quality DHA and EPA triglycerides, with published 3rd party tests. It is in many ways a perfect omega-3 supplement, and it focuses only on providing omega-3 fatty acids. It lacks the natural processing which the higher end product have, and so lacks the additional co-factors, but this is by no means a major concern. I would recommend this to anyone who wants a highly concentrated omega-3 supplement, and it is particularly suitable for athletes.4-stars
  7. Rosita EVCLO – Rosita EVCLO a very natural cod liver oil, and very comparable to Dropi’s cod liver oil. It doesn’t contain the additional metabolites that Green Pastures does, but the omega-3s and vitamins are all natural and highly absorbable. This is a clearly a nutritious product, and has 3rd party testing to prove the quality, but its just a shame about the price, which might put it out of reach for most people. 4-half-stars
  8. Green Pastures cod liver oil – Fermented cod liver oil is a natural product, which has the added benefits of co-factors and vitamin metabolites which are produced by the fermentation process. The omega-3s are triglycerides, there is 3rd party testing and the minute amount of processing makes this one of the top omega-3 supplements. However, I would really like to have the 3rd party tests available on a 3rd party website, and the varying nutrient content makes it a little unreliable, but that’s unavoidable.  4-half-stars
  9. Dropi EVCLO – Dropi’s cod liver oil is very comparable to Rosita’s EVCLO in quality and production. The oil is very naturally processed, the fats are in the natural triglyceride form and the vitamins are all in their natural form alongside their metabolites. It would be nice to have their lab results made public, but in all communication they have been very co-operative and helpful, and I have no reason to believe their lab results are showing anything other that what they claim. As with the other high quality cod liver oils mentioned here, the price might be prohibitive to some, but it is amongst the best cod liver oils available. 4-half-stars

Both Green Pastures Fermented Cod Liver Oil and Rosita EVCLO have scored really highly. They are both very good quality products and you can a more detailed comparison of them here.


Comparison Table

Let us know what fish oil you use and why!

Disclaimer: All images are copyright to their respective owners.

I hope you enjoy the site, and like what we have worked hard to create, any feedback is very much welcome, after all this site is for you! Graduate of Nutrition & Food Science (Bsc) at Reading Uni.
  • Zilster

    According to the website , Natures best fish oil provides FAR more DHA
    & EPA than the others , yet in this article the Natures Best fish
    oil is completely written off as a waste of time , or at best a ‘top up’ … Whats going on???

    • Hi Zilster – of course Natures Best would say theirs is the best…if the product is the same one that is in this article, then you can clearly see that the DHA and EPA are much lower than others.

      • Zilster

        Hi Craig , They say …
        ”Highly concentrated source of Omega 3s
        EPA 360mg and DHA 240mg in each capsule”
        1100mg capsule.

        Wouldn’t that come under false advertising if it wasnt true?
        Guess I should go for the more costly proven ones.

        • Hi Zilster,

          I’ve had a quick look at their site – looks like you are looking at the fish oil product, whereas here I talk about the cod liver oil product (very similar products).

          The EPA and DHA levels are higher in their fish oil, although there won’t be any vitamin A or D. They are also not the highest amounts of EPA or DHA of fish oils- have a look at Carlson Labs oil (2nd product in this comparison).

          Personally, I like the green pastures products – big fan of minimal processing and 3rd party testing, but sadly you pay for it, and also the EPA and DHA aren’t consistent.

          Swings and round-a-bouts I guess. Natures Best is a big brand, and I would like to think their products are good sources of EPA and DHA, however, without 3rd party testing you can sadly never know.

          • Zilster

            Thanks Craig , Iv never really thought about how it all works , your input helped , il continue to research and hopefully pick a quality one to try , thanks again.

  • Mindbody Medic

    Could you possibly add Paradox Oil to this comparison and also what dosage for each? possibly harmonise dosages(if this is not already the case?) if you use the email the founder will contact you and provide details Im sure if you tell him what you are doing.

    For example make each profile 15ml dosage and corresponding contents for each?

    thanks for this comparison , really helpful!

  • John Chandler

    Hi, Just to say thanks for this in depth discussion. Found it very helpful as about to start my partner on `omega three supplements as she is breast feeding two premature babies. Your in depth analysis saved me a lot of time (don’t have a the moment and worry (that i have rather a lot of at moment). Will go with your recommendations and hopefully give my two new little daughters a little advantage. Thanks and a
    ll the best John.

  • daz

    slightly off topic Craig…
    Carlson have an ingredient they call Re-esterifi ed Triglycerides (rTG).
    see here for details;

    What do you make of it….? any thoughts


  • daz

    slightly off topic Craig…
    Carlson have an ingredient they call Re-esterified Triglycerides (rTG).

    What do you make of it….? any thoughts


    • The Re-esterified triglycerides sound to be better than the standard ethyl esters, but Carlson’s say that they have the same potency as th ethyl esters, which would mean that they are not as well absorbed as the natural triglycerides. This may be because the fatty acids have been ‘re-jigged’ and are not in a natural state anymore. I.e the fatty acids chains that are attached to the glycerol backbone are not in a form that you would find them in nature. If I had to chose for myself (based on a gut feeling), I would go for the natural TGs over rTG, but I would go for the rTG over the EEs (if that makes sense) 🙂

      I’ve never come accross these rTGs before though, thanks for bringing it to my attention. I’ll look into research into absorbancy.

  • Iain

    Hi, I use GNLD Neolife Salmon oil. Cold pressed from the best bits of fish sourced from pristine oceans.
    Has all eight omega 3 , rather than just two, hence it is complete. Been tested for over 200 contaminants, has studies to prove effective in reducing cholesterol .

  • Annette

    Hi Craig, I’ve always wondered about fish liver oil. One of the liver’s functions in the body is to get rid of harmful substances, thus I’m with Iain about about using a salmon oil made from edible parts of fish, rather than fish liver oils, because this may explain why fish oils are so often contaminated by mercury and other heavy metals.

    • Hi Annette,

      Good point. Most fish liver oil will be filtered and tested for mercury and other toxins, so you are usually pretty safe (especially if you stick to a well known brand).

      Some brand will source their fish from very clean water where to levels of toxins are extremly low so they don’t even need the filtering done (they are of course, still tested for toxins).

      Hope this helps.

  • Mrsp


    Any review on Wild Nutrition?


    • There isn’t a great deal of information on their website. It is sourced from sardines/ anchovies like PurePharma is, so it might be a comparable product. However, you would have to contact them for information on processing/ testing/ fatty acid form.

  • Dropi Extra Virgin Cod liver oil, it’a awesome and this oil reflect is working very uesful. thank for sharing about Dropi Extra Virgin Cod liver oil information

  • Jas

    Great stuff. Really useful information. Thanks.

  • Nick Evans

    Hi mate.

    With ref to the seven seas product you choose to display.. there are other SS products out there with absolutely mega amounts of omega 3 in. I use one that has 1500mg of a mix of Omega’s 3… 300ml bottle for £6 so 20p per 10ml…. ..

    • Hi Nick,

      Yes you are right, SS do a number of products, and from speaking with them their liquids not only prove to be better value, but often better quality. They have a massive range, so I couldn’t include it all though! 🙂

      • Nick Evans

        Hi. I’ve been in touch with them over the last few weeks regarding their products. They have provided me with extensive information regarding their products, the extraction process where their sourced from amongst other things. They have also just told me that All their liquids are triglycerides! Have you done any articles Astaxantin? Thanks

        • Hi Nick,

          Yes, I’ve been told that all their liquids are triglycerides too! I don’t fully understand why only their liquids are though… When I spoke with them they told me they cannot provide any details on their processing methods as it is considered to be ‘commercially sensivite’. What did they say about it to you?

          I can put astaxanthin on the to-do list for you 🙂

          • Nick Evans

            Hello Nick
            Thanks for your message.

            Food contamination has become an issue of major concern and it is certainly true that fish from certain seas have been shown to contain small amounts of environmental pollutants. In the case of fish and fish products the levels of contamination can often be related to the source and age of the fish. Levels are much lower in fish from open waters, as in the North Atlantic, Arctic and South Pacific Oceans, with higher levels of organochlorine and heavy metal contamination occurring in fish caught in coastal waters and in landlocked seas. Seven Seas cod liver and fish oil products are predominantly produced from fish caught in open waters which have extremely low levels of pollution.

            Seven Seas have been routinely monitoring all production for over 15 years. Continuous extensive testing and quality control is carried out on the fish oils at each stage of the purification process and they are checked regularly from the raw material stage right through the processing and bottling or encapsulation of the oil. This includes monitoring and testing for pollutants to ensure that Seven Seas Cod Liver Oil and fish oil is completely safe and free from harmful levels of pollutants.

            Analysis for contaminants is carried out on our behalf by UKAS accredited laboratories using a variety of techniques including Low and High Resolution Gas Chromatography – Mass Spectrometry. All of our products comply fully with current EU and UK legislation addressing contaminant issues.

            Looking to the future the important factor is that manufacturers and government agencies recognise the problem of pollution and work together to eliminate it. There are many working parties continuously monitoring food supplies in the UK for just such contamination, and reporting regularly on their findings. The Department of the Environment also plays its part in issuing guidelines on emissions into the environment, as control of the emission of these materials is the only route by which, in the longer term, levels can be reduced. There is already some evidence, relating dioxins, furans and PCB’s to indicate that worldwide initiatives in this direction are gradually improving the situation.

            There is no doubt that any PCB’s and other environmental pollutants are undesirable and with the latest detection methods minute levels can be found in all samples tested (including competitors) by our own methods, but at the levels found at present, the huge and proven benefits arising from consumption of fish oils vastly outweigh the tiny likelihood of any adverse effect from these minor contaminants. We hope that you will accept our reassurance that you can trust the Seven Seas brand and be reassured by the fact that Seven Seas has over 80 years experience in producing Cod Liver Oil and fish oils, and that they are safe and free from harmful levels of pollutants.

            We blend our Cod Liver Oil with Fish Oil, as this will provide a much higher level of the omega 3 fatty acids, gram for gram, than using Cod Liver Oil alone. The fish we use will be a mixture of oily fish, which are predominantly the smaller fish such as mackerel, sardines and herring, although some salmon and tuna may also be present.

            Kind regard

            Next email

            Hello again Nick,

            The oil is rendered by mashing the liver and extracted from the livers of cod by gentle heating. However, the resultant ‘raw’ oil is not suitable for human consumption and must, therefore, undergo some processing. The oil, water and residual proteins are then separated by centrifuging to produce a crude oil. This oil is then acid/alkali refined, cold cleared and deodorised to make it palatable and fit for human consumption.

            Kind regards

            Next email
            Hello Nick,

            Some of the vitamins are lost during this process and will need to be added back into the oil so that every batch contains the same, stated level. Which vitamins we add will depend on the product as many of our cod liver oil products do not provide vitamin A. This is in response to our customer feedback which suggested that many people want to take cod liver oil with a multivitamin as well.

            Kind regards

            They were the three emails.

          • Hi Nick,

            Thanks for sharing those emails with us – appreciated 🙂

  • I am being printing this
    page.thank you.

    Zuly Zonova
    Owner of

  • Sally Brantley

    There is a new UK made fish oil on the market made by Bare Biology which is made from triglycerides and is also third party tested by IFOS. It is quite expensive, but it looks really good!

  • Steve Tallent

    On GPP, it says that the fish are sourced from Arctic waters. That’s not true according to GPP website. They are sourced from the Pacific Ocean, below the arctic circle, as far south as the top of Alaska, if I recall correctly. Besides keeping the livers cold, how does Dropi get the oil out. Are the livers pressed?

    • I beleive that their fish are from the Baring Sea, which is very much part of the Arctic regiion (the region where the average temp is lower than 10C). Arctic circle and arctic region are different things, and they are highlighted on this map here: The red line is the Arctic region, which includes Northern Alaska and the Bering Sea (there is clearly some cross over in regions TBF).

      Here is some info from Dropi (their livers are grinded up):

      We use only fresh material from the local fishing boat fleet, the lonliners and jiggers. The fresh livers are taken to the processing facility, located only a few steps away from the fish market, first step; the livers are grinded. After grinding the livers, the precious oil is then seprated from the livers using low temperatures (<42°C). The fresh cod liver oil is then moved to a seperate tank, filtered and chilled. The oil is stored in a nitrogen filled (oxygen free environment) tanks untill bottling.

      The setup and the processing steps are simple and environmental friendly. The processing method was designed to be as natural as possible and to avoid harsh industrial refining of the product.

      Hope this helps.

      • Steve Tallent

        I should have noticed the date of this article before commenting and I didn’t and I’m sorry. Just a little explanation for the benefit of your readers: the Bering Sea is indeed an alternative definition of the Arctic Region according to wikipedia. However, it is not the common definition understood by most people. And by the natural science definition, the Bering Sea is considered subarctic. Given all of this, in the midst of the big Green Pasture expose´ last year, there was an outcry from GPP customers that “Arctic Waters” was misleading causing many to think they were using Atlantic Cod when they were actually sourcing from the other side of the world and using Pacific Cod and Alaska Pollock. GPP responsibly scrubbed any reference of Arctic waters from their website. They have replaced it with a variety of statements including “in and around the Bering Sea region and in the general area of the Aleutian Islands”, , “Bering Sea/Aleutian Islands region” (which also appears now on their labels) , and “Alaska” in an article on their site by Sally Fallon Morrel, with the most recent reference being “North Bering Sea” . I applaud the increased clarity, transparency, and accuracy as it will help consumers make informed decisions.

The Health Cloud was created in December 2011 by Craig and Morg who have been friends since high school. Our focus is to educate our readers with unbiased health articles and on the side we run our own online health shop. This website is for you, so drop us a comment or send us a tweet, we always take the time to reply!