Separating fact from fiction on cod liver oil

cod

I’ve received several questions about the safety of cod liver oil (CLO) since the Vitamin D Council warned consumers about the ingestion of CLO due to concerns about potential vitamin A toxicity in their November bulletin.

Sally Fallon, president of the Weston A. Price Foundation, recently wrote a letter to members clarifying the issues raised by the Vitamin D council and exonerating cod liver oil.

If you’re having second thoughts about the health benefits of CLO, please read this and pass it on to anyone you know who currently takes or is considering taking cod liver oil.

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Dear Members,

We are obliged to issue another official statement on cod liver oil after the November bulletin of the Vitamin D Council, which contains “an unprecedented warning about the ingestion of cod liver oil and resultant vitamin A toxicity.”

The warning accompanies a report on a review article co-authored by Dr. John Cannell, head of the Vitamin D Council, and fifteen other researchers, entitled “Cod Liver Oil, Vitamin A Toxicity, Frequent Respiratory Infections, and the Vitamin D Deficiency Epidemic” in the November issue of Annals of Otology, Rhinology and Laryngology.

NO PROOF THAT VITAMIN A IS TOXIC
Most of this paper is a review of studies showing the benefits of vitamin D in protecting against various illnesses, including respiratory infection. THIS PAPER DOES NOT PRESENT ANY INFORMATION WHATSOEVER INDICATING THAT COD LIVER OIL IS TOXIC, and, in fact, admits that vitamin A can significantly reduce the incidence of acute lower respiratory tract infections in Third World children.

A portion of the review article is an attempt to explain why a 2004 study providing 600 to 700 IU of vitamin D and 3,500 IU of vitamin A in the form of cod liver oil and a multivitamin failed to meaningfully reduce upper respiratory tract infections when studies from the 1930s found that cod liver oil could reduce the incidence of these infections by 30 to 50 percent. The authors of the recent commentary suggested that the older studies were more effective because cod liver oil in the 1930s contained much more vitamin D. They suggested that modern cod liver oil is low in vitamin D because the deodorization process removes the vitamin while manufacturers fortify the oil with only a fraction of the original amount. As an example, they cited cod liver oil made by Nordic Naturals, advertised as containing only “naturally occurring vitamins A and D,” which has only 3 to 60 IU of vitamin D per tablespoon but between 150 and 12,000 times as much vitamin A.

This conclusion is essentially the same as the conclusion reached by the Weston A. Price Foundation and the research of Chris Masterjohn; we have continually pointed out that vitamins A and D work together and that without vitamin D, vitamin A can be ineffective or even toxic. We do not recommend Nordic Naturals regular cod liver oil or any brand of cod liver oil that is low in vitamin D. But it is completely inappropriate to conclude from this 2004 study that cod liver oil is toxic because of its vitamin A content. Similar reviews could be put together showing the benefits of vitamin A and cod liver oil in numerous studies, including the studies from the 1930s. Obviously the solution is to use the type of cod liver oil that people took in the 1930s, which did not have most of the vitamin D removed by modern processing techniques.

Our recommendations for cod liver oil brands can be found here.

Healthy Skeptic note: I recommend either high-vitamin cod liver oil or fermented cod liver oil from Green Pasture and Wolf River Naturals.

VITAMIN A DOES NOT ANTAGONIZE VITAMIN D
The Vitamin D Council report claims that the vitamin A in cod liver oil is excessive and antagonizes vitamin D by inhibiting the binding of its active form to DNA and thus preventing its ability to regulate the expression of vitamin D-responsive genes.

Vitamins A and D are both precursors to active hormones that regulate the expression of genes. The body possesses certain enzymes that convert each of these in a two-step process to their active forms: vitamin A is converted to retinal and then to active retinoic acid while vitamin D is converted to calcidiol and then to active calcitriol. While directly consuming either retinoic acid or calcitriol would be unnatural, consuming vitamins A and D, together, as in cod liver oil, is perfectly natural. The enzymes involved in these conversions are responsible for producing incredibly powerful hormones and are therefore highly regulated.

In order for vitamin D to activate the expression of its target genes, it must bind to the vitamin D receptor (VDR) and then combine with the retinoid X receptor (RXR), which is activated by a particular form of vitamin A called 9-cis retinoic acid. RESEARCHERS FROM SPAIN RECENTLY SHOWED THAT VITAMIN D CAN ONLY EFFECTIVELY ACTIVATE TARGET GENES WHEN ITS PARTNER RECEPTOR IS ACTIVATED BY VITAMIN A.

In the ABSENCE OF VITAMIN A, molecules called “corepressors” bind to the VDR/RXR complex and PREVENT vitamin D from functioning.

The molecular biology of 9-cis¬ retinoic acid, however, is extremely complex, and this has led to some confusion. The RXR and its activator 9-cis retinoic acid partner up not only with the vitamin D receptor, but also with the receptors for steroid hormones, thyroid hormone, and most other nuclear receptors. In fact, if enough 9-cis retinoic acid is present, RXRs will even partner up with themselves. Ordinarily, this versatile form of vitamin A is gradually derived in small amounts from the larger pool of all-trans retinoic acid as needed. When scientists add large amounts of 9-cis retinoic acid to isolated cells, then, it may cause effects that smaller amounts naturally produced in the cell would not cause.

Researchers have shown, for example, that 9-cis retinoic acid interferes with the ability of vitamin D to stimulate the production of osteocalcin, a vitamin K-dependent protein involved in organizing the mineralized matrix of bone. This may have been because the excessive amount of 9-cis retinoic acid caused RXRs to pair up with themselves and thereby made these receptors unavailable to vitamin D. When scientists incubate cells with activated vitamin D and all-trans retinoic acid, ordinarily the source of 9¬-cis retinoic acid in the cell, the two hormones stimulate the production of osteocalcin with remarkable synergy.

More information on the interactions between vitamins A and D can be found in these articles:

Vitamin K2

Does Vitamin A Cause Osteoporosis?

Vitamin D Safety

The Spanish research demonstrating the necessity of 9-cis¬ retinoic acid for the functioning of the vitamin D receptor can be found here, and here:

PLANT FOODS ARE NOT A GOOD SOURCE OF VITAMIN A
In the December Vitamin D Council newsletter, Dr. Cannell further claims that consuming preformed vitamin A is “unnatural” and that the body highly regulates the conversion of carotenoids found in vegetables to vitamin A as needed. However, the enzymes that convert carotenoids to vitamin A are less critically maintained because they are unneeded when preformed vitamin A is provided in the diet-as it usually is. They are therefore, like the enzymes that convert essential fatty acids in plant oils to their elongated and desaturated forms, subject to variations in genetics, circumstantial health, and dietary and environmental influences.

Many factors can interfere with the conversion of carotenoids into vitamin A including thyroid problems, liver problems, diabetes and genetics. Babies and children convert carotenes very poorly if at all.

The statement that preformed vitamin A is unnatural is ludicrous in the light of what we know about traditional diets. The chief source of calories in the traditional Inuit diet, for example, is seal oil, which Weston Price found to be higher in vitamin A than cod liver oil. Fish heads, extremely rich in vitamin A, are a staple in the Japanese diet. Many cultures consume liver, often in high amounts-yet the authors of the review paper imply that liver is toxic. Tell that to the Frenchman enjoying his foie gras, the Englishman consuming liver and onions, or the South Sea Islander who submits to great danger to obtain shark liver for men and women, in order to ensure healthy children. The truth is that pre-formed vitamin A is more plentiful in traditional foods than vitamin D, yet politically correct nutrition insists that we must obtain vitamin A through the laborious process of converting carotenes.

More information on the conversion of carotenoids to vitamin A can be found in this article and this one: (see the section “Vitamin A Vagary”).

COD LIVER OIL IN PREGNANCY
The Annals paper does not cite any studies showing toxic effects from cod liver oil, but Dr. Cannell cites one study in his December newsletter associating intake of cod liver oil with hypertensive disorders during pregnancy. Users of cod liver oil in this study had about twice the intake of vitamins A and D as non-users and eight times the intake of long-chain omega-3 fatty acids. The study found the most robust association with long-chain omega-3 fatty acids, which were associated with lower risk between 0.1 and 0.9 grams per day and higher risk above 0.9 grams per day. The authors suggested that the association with high blood pressure might be related to oxidative stress caused by a high intake of polyunsaturated fatty acids.

The abstract of the study can be found here:

The new Annals article offers nothing new to incriminate cod liver oil. It provides a well-written argument that vitamin D intakes need to be higher and incriminates only highly processed modern cod liver oils that have inadequate amounts of this critical nutrient. We recommend only high-vitamin cod liver oils that provide abundant vitamins A and D without an excess of polyunsaturated fatty acids.

THE COD LIVER OIL PUBLIC HEALTH INITIATIVE
As we pointed out in our last update on cod liver oil, during the first half of the century, cod liver oil was the focus of a worldwide health initiative. Parents were urged to give cod liver oil to their children by doctors, by government officials, by teachers and principals in schools, and even by their ministers in churches. A large portion of adults in America born before the Second World War received cod liver oil as children and this practice contributed to a high level of health, intelligence and physical development in those lucky enough to receive it. In many European countries, children received a daily ration of cod liver oil, especially during the war years. In the UK, for example, the government issued cod liver oil to all growing children until the early 1950s.

What has led to the demise of this obviously beneficial practice? Cod liver oil is a food; it can’t be patented, it can’t be created in a laboratory; it can’t create millions for the drug companies. So interest in this wonderful superfood has naturally waned. But if you are basing your dietary habits on the principles of healthy nutritional diets, don’t hesitate to include cod liver oil-our recommended brands of cod liver oil–as a healthy and natural food source of critical vitamins so lacking in modern diets.

Sally Fallon, President
The Weston A. Price Foundation

recommended links

  • Dr. Ron’s: a great place to purchase Blue Ice High Vitamin and Fermented Cod Liver oil.  I also like Dr. Ron’s line of additive-free supplements.

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Comments Join the Conversation

  1. Javier says

    I don’t understand if people are against polyunsaturated oils why is fermented cod liver oil ok?

    Polyunsaturated oils are VERY unstable, oxidizing quickly when exposed to oxygen, light and heat—even just sitting in a bottle, but also when they go into our bodies—and turning rancid. (including omegas) Also Fermented foods require a glucose source to create (metabolize) a by-product e.g. lactic acid that prevents the food from decomposing. The result is a pleasant sour taste that one would find with sauerkraut, pickles, yogurt, etc. Cod liver oil has no glucose and cod livers have very little glucose (mostly protein, fat, water and some minerals). The livers and the oil simply go from fresh to rancid in a short period of time. If left to continue decomposing the oil will become putrid leaving a foul smell and taste.

    Furthermore, Cod, like Shark, are long-lived fish. As they go about living for years and years, and during that time, they accumulate environmental toxins.
    And the toxins are most concentrated in the livers. So when you drink Cod liver oil, you should expect environmental toxins! That just makes sense!

    Sadly, atlantic Cod is an over-fished and threatened species.

    Why not just eat more fish and liver and gain similar yet better benefits since it’s a food source?

    • Molly Malone says

      Hello Javier, you’re correct, fermented cod liver oil isn’t really fermented at all, it’s rotted. (My post above yours links to and quotes an article explaining this.) I don’t use it though I did buy a bottle and use the entire thing (shouldn’t I get some sort of award for that?). It doesn’t agree with me or with my husband, so we’re done with it.

      Good cod liver oil cannot be found in America, it has to be imported from other countries that don’t heat the life out of it and thereby ruin the vitamins. All US cod liver oil has been heated/distilled and synthetic vitamins have been added back in. There are decent cod liver oils but the vitamin A is synthetic and therefore incomplete. Genuine, natural vitamin A is a mixture of 14 different molecules, synthetic is usually just one. Not the same, sadly. There is a link in the article above that lists the different decent brands in the USA. I have used Sonne’s and Carlson’s, they are each palatable.

      The liver doesn’t store toxins, that is a misconception. The liver detoxifies them, however, the liver is not a storage organ. This fact makes it a valuable food source for vitamins A, D, E, K, B12 and more, as it does store those foe detox purposes. Chris has an excellent article about this:
      http://chriskresser.com/natures-most-potent-superfood

      I agree with you about eating liver, too. Some people cut up raw grass-fed beef liver into small pill-sized bites and freeze them, and then just swallow one whole as a “pill” to get raw liver. I have not tried this, just read and heard about it.

      Liver is a food, and cod liver oil is a food as well, but I’m really not sold on the rotted version of cod liver oil.
      http://www.ratfishoil.org/oil-in-the-exact-form-it-is-found-in-the-liver

      • Molly Malone says

        By the way, just to be clear, I am all for cod liver oil, and if fermented agrees with you then use it by all means; it is the only one in the USA that has the genuine, non-synthetic vitamins in it. The process of fermenting it does not agree with me or my husband, who can usually stomach just about anything. Our kids won’t go near it, so we use non-fermented, imported from Norway.

        • javier says

          I think you missed my point. The trouble with this approach is that omega-3 fats are chemically fragile: their carbon double bonds are easily oxidized. EPA has 5 double bonds and DHA 6 double bonds, so they are the most vulnerable of all dietary fats. They easily become rancid. Fish oil capsules often sit on a shelf for months before they are eaten. If someone offered you the opportunity to eat salmon that had been sitting on a shelf for six months, would you do it? No? Then why accept the same deal with salmon oil?

          In fact, clinical trials have compared eating fish to eating fish oil capsules. Fish consumption has an excellent record in a number of clinical trials, but fish oil capsule supplements do not.

          In the Diet and Angina Randomized Trial (DART-2), 3114 men with stable angina were followed for 3-9 years. There was a control group, a group advised to eat oily fish like salmon, and a group taking 3 fish oil capsules daily. There was a significant increase in sudden cardiac death among the subgroup taking fish oil capsules. http://pmid.us/12571649.

          I will not take a supplement where I have doubt that it is helpful or might even be harmful. There are numerous voices from different camps that question if fish oil is healthy. And more critics seem to pop up every year.

          Good tip on the frozen liver! Thanks

          • Molly Malone says

            Hello Javier,
            Maybe, but I thought I got it, and I do agree with you: oxidized oils are bad for health. I was trying to show my agreement by stating that FCLO may in fact be rancid, meaning oxidized. There have been a few studies on this. The manufacturer of the FCLO claims that it is in fact lacto-fermented, however. Myself, I don’t know, I only know that the WAPF has never steered me wrong yet, and they recommend FCLO. I also know that after downing one bottle, I cannot ever eat another milliliter of the stuff. Perhaps this is just my problem, I am a fussy eater, and though I don’t have any food allergies, it did ultimately make me nauseous. Others may find it just fine.
            http://www.culturesforhealth.com/lacto-fermenting-meat-fish-part-one

            http://www.culturesforhealth.com/lacto-fermenting-meat-fish-part-two

            Regarding rancidity, yes, unsaturated oils are very fragile, whether from fish or plants. Lots of data on this. That’s the trouble with eating just the oil, isn’t it? It’s always processed in some way, which generally ruins it through oxidation, though not always. Some manufacturers add antioxidants to their fish oil and cod liver oil, Carlson adds a small amount of vitamin E. This does nothing for oils already ruined in the processing, however.

            Which leads me to the next point – quality. Not all fish oils, and not all cod liver oils are created equal. There are vast differences in quality and therefore nutrient levels and rancidity. Not all brands are rancid, but a good many are, and nobody should be eating that. If you don’t want to take CLO, that’s fine. If you do, you will want to find a very reputable supplier that will tell you what they do and how they do it. After all, you’re trusting them with your health.

            Did you look at my link above? Rosita makes their cod liver oil very, very differently and because of this it should not be rancid, and could be considered as a possibility.
            http://evclo.com/

            http://www.rositarealfoods.com/general-information/1-the-age-old-ways-of-extracting-liver-oil

            http://www.ratfishoil.org/oil-in-the-exact-form-it-is-found-in-the-liver

            As far as fish sitting for 6 months, that could be canned or jarred tuna or salmon, and I do eat it with no ill effects at all. It is not rancid, but wild caught and sustainably harvested and canned in glass. The point being again that it’s all in the quality, meaning ingredients and processes used to prepare. If the oil is from wild fish, if the oil has been properly obtained, and if the oil has been properly preserved using essential oils and/or mixed tocopherols or something else, then it will likely be very good. If not, well, all bets are off.

            I read the abstract you linked to, but because I cannot read the entire study I question its validity though it is certainly thought provoking. For example, was the fish farmed or wild? Which fish oil caps (what quality) were used, and again – farmed or wild? How did they arrive at a 3 caps per day dose – that seems a bit low; in order to equate to 1t of the oil usually 5-10 caps are needed, depending on the size of the capsules. How was the oily fish prepared? Breaded in glyphosate loaded flour or GMO corn meal, then deep fried in oxidized canola oil, perhaps? Or pan fried in canola? Canned in soy oil? Was a heavy flour – margarine and low-fat pasteurized milk sauce poured over? Or heaven forbid a “sauce” made from low-fat condensed soup? It’s all in the quality of the food and in the preparation methods. What else did the men eat? Did they feel that 2 servings of oily fish per week gave them leave to eat all sorts of not-so-great food because they thought the fish was compensating? I have no idea, I can’t read the study, but rarely do these sorts of studies take the above concerns into consideration – the study designers probably wouldn’t even understand the reasons for my concerns. Many doctors don’t, either, including one research doctor (Md) I spoke with who shouldn’t be allowed anywhere near a lab.

            I also agree that it is better to eat the whole fish rather than take any kind of oil at all. This is not always possible, however, if a person needs a lot for whatever health reason they may have. This is why finding a good supplier is so important – you want the best quality that you can afford. I don’t believe that all fish oils and all cod liver oils are oxidized, and those in liquid form seem to be a better quality than the encapsulated ones, even from the same company. I’ve tried both from Carlson’s and prefer the unflavored CLO liquid; I sent the caps back. Never eat rancid food, including oil containing gelcaps or CLO caps.

            Some people cannot simply eat nutritious, organic whole foods and be done with it. Some people can; for some, food is enough because their health is quite good. For others that have big health issues, food may not be enough and supplements may be necessary – which is the reason for cod liver oil in the first place, and why finding an excellent source is so important. It is claimed that cod liver oil is a food, but it is also like a supplement, and rides the thin line between the two.
            Stay well!

            • julielu says

              Thank goodness for your comments Molly / Javier and Leah. I hope others also hear your views loud and clear!

              Investigation is essential to make sure the value we expect from the product is really available. The taste of FCLO says it all.

              I think It is misleading that this product is termed “fermented” if it leads to misinterpretation. The fermentation of the cod livers is an implied health positive when in fact it is only a processing means i.e. a technical way to separate the oil from the base product.

              “Fermented” – ness is not a quality of the oil and cannot be included in the end product. An oil is not fermentable (as it does not contain carbohydrate) but it is very subject to rancidity. It is my belief that rancidity is contributing to the awful taste of FCLO.

              Also out of curiosity, (as I would not be paid to have anymore FCLO) can anyone confirm the source of the D2 in the FCLO please?

              • Molly Malone says

                Hello julielu,
                Thank you. I think it’s misleading too, though I could be wrong here. And I agree about the taste. Our home chemistry lab is all on our face, look at it, smell it, and lastly taste it. If it looks off, smells off, tastes off – it’s off! Actually, if it looks and smells off, don’t taste it at all, that could be dangerous.

                The owner of Green Pastures claims his FCLO is lacto-fermented, but he doesn’t explain how so I am skeptical. Because I’ve read almost all of the rositarealfoods site, pictures and links and all, and a lot of it more than once, I am twice skeptical. Here’s what I think: unless something is added to the cod livers, it’s rotted and not fermented. Here is a link to what he (Dave Wetzel) says:

                http://www.westonaprice.org/health-topics/update-on-cod-liver-oil-manufacture/
                “The method we have developed processes the cod liver oil through a proprietary non-heating natural lacto-fermentation. The process can take up to six months and is carefully handled throughout the process to ensure the oil is clean and natural. Industrialized fish oils, including cod liver oil, are heavily carbon filtered and heated after rendering or extracting. We have developed a unique cleaning process that does not use carbon filters or heat. Both heat and carbon filters remove flavors, odors, colors and nutrients, and also denature the fragile unsaturated fatty acids such as DHA and EPA.”
                “My other task was to find the livers. The search began several years ago—I picked up the phone and made many cold calls, most of which got me nowhere. People said I was crazy to want to purchase thousands of pounds of cod livers. Finally I met a Russian who took an interest in the project and found the livers for me—in Russia, they know about cod livers.”

                Now, while this sounds good, the stuff tastes very bad and upset my (cast iron!) stomach, to say nothing of my sensitive taste buds. Furthermore, my husband loves all things properly fermented, including but not limited to: sauerkraut, turmeric kraut, pickled anything, and kimchi. He loves bleu cheese, and the bleuer the better! He hates this stuff, even more than I do. If it’s lacto-fermented, I want to know how it’s done before I buy it ever again. As it’s proprietary, I seriously doubt I’ll ever find out.

                My main concerns about this FCLO are these:
                1 – The livers are not fresh, they’re frozen (which if you’re going to rot them, may not matter)
                2 – There are many flavors of this FCLO – none of them organic or natural as we think of natural. Their flavors are ALL synthetic, a chemical cocktail that is dangerous.

                Why is it dangerous? Because every single “natural flavor” is a mixture of any of 4,000+ FDA approved chemicals made in a lab (mostly in NJ). I am suffering from an allergic reaction to one such mix even as I type this, from a “natural” flavor in my new-and-now-in-the-garbage B12. It is not fun, it is miserable and it could have been worse if it had thrown me into anaphylactic shock: I could be dead. I have no food allergies at all, but foreign chemicals are another story altogether. Because of this danger I will not use flavored cod liver oil – ever! If I can’t stand the taste I add organic essential oils to the stuff; how difficult is that for a manufacturer to do? I’m not impressed…

                By the way, I’m not the only one that has been affected by this “fermenting” process:
                http://nourishedandnurtured.blogspot.com/2013/01/why-we-stopped-taking-fermented-cod.html

                Which leads me to my next opinion (meaning discard at will, I’m not an expert). I’m only on day 2 of my ratfish oil from Rosita Real Foods, but it’s lovely. I take 10 DROPS every morning. This oil is very mild, and a person needs so little of it that it hardly matters how it tastes. It is clear, and pale straw in color. This I can do, forever if necessary, the FCLO I cannot.

                I think Rosita has a good product, and I bought it to try. Take a look at their site and read about their cod liver oil and their ratfish oil, they have a very pure source of fish, fresh and not frozen and not imported! They also have unique extraction methods, the best I’ve ever read about or seen in pictures. By the way, if you email them with questions, they really do answer!

                (Chris, you know more about everything health than I do, see what you think too, please.)

                Here are a few links for all to check out, please read first before you buy because this is very expensive stuff, wouldn’t you just know?! [Maybe a group can get together and do a big order to get the better price… just a thought.] They also have videos on a few of their pages, those are fun.

                http://ratfishoil.net/ The order page

                http://www.rositarealfoods.com/ Their home page

                http://evclo.com/fatty-acid-levels-fish-oils/ All about rancidity – Javier might like this page, I did. One more reason to suspect FCLO and find quality oils.

                http://www.rositarealfoods.com/rosita-evclo-faq You have questions? They have answers!

                http://www.rositarealfoods.com/rosita-evclo-faq/15-cod-liver-oil-articles/faq/6-rosita-real-foods-evclo-faq#EVCLO-FAQ-8 The oil was tested for D3, along with everything else. It’s in the oil naturally. Nice!

                http://www.rositarealfoods.com/rosita-evclo-faq/15-cod-liver-oil-articles/faq/6-rosita-real-foods-evclo-faq#EVCLO-FAQ-17
                “How can you ensure that your EVCLO is not rancid both upon purchase as well as later, when it has been at home? What is the proper way to store EVCLO so that it does not become rancid?

                Rosita has gone to great lengths and expense to create an antioxidant package that will keep EVCLO fresh during transit, storage and consumption. Due to cod liver oil’s propensity to go rancid very quickly Rosita drew upon the expertise of scientists, researchers and university Professors to determine the proper antioxidants that were both effective, and most importantly to Rosita completely natural. Only tiny amounts of natural antioxidants are added which is simply the bare minimum required to stabilize the oil. This is actually very important because too much antioxidant can actually promote oxidation. Temperatures are kept very low during bottling, no reactive metal ever comes in contact with the livers or the oil, production is carried out in the absence of oxygen, the time between catching the cod and bottling the oil is very short, and smaller bottles are used to ensure the oil would be consumed long before it goes rancid. EVCLO can be shipped without dry ice or cold packs however once received it should be stored in the refrigerator. Unopened bottles can be kept in the freezer for long-term storage. Once you receive your bottle of Rosita EVCLO, it is preferable (but not essential) that you leave your EVCLO under cold-storage for 24 hours prior to opening the bottle and consuming the oil. Remember to gently shake the bottle before use.”

                Evidently, they take the rancidity issue very seriously, and they’re not too thrilled with so-called fermented cod liver oil either. Now, as this is a Norwegian company, and these people are in Norway, they pretty much have access to all the fish and all the traditional methods they want. There has to be a reason that they don’t make “fermented” oils!

  2. Leah says

    I’m not sure the best article to post this question. My husband is allergic to scallops; while he has not had a formal allergy pannel done, he has had anaphylactic reactions both times to scallpos, and accordingly, doesn’t consume shellfish.

    What would be good alternative(s) to the Blue Ice green pasture CLO you recommend?

    I’ve read that a combination of Butter Oil/dessicated liver capsules for A, D, K2 would be good. But what about for omega-3s?

    Thanks for your suggestions.

    • Julielu says

      Tom, A very interesting question! I recently called a company on promoting misinformation for stating that the FCLO mostly contained Vit D2. But I was very wrong! – The D2 in FCLO IS mostly D2 i.e. Ergocalciferol i.e. not D3 Cholecalciferol that is made in animals. Elsewhere it has been stated that D2 is not found in either cod liver or cod flesh!

      Is it a result of the fermenting process itself?
      Therefore perhaps no more ‘natural’ than the D2 synthesised by irradiating mushrooms or bread yeast or by obtaining D3 from irradiated lanolin from sheep’s wool?

      Earlier research re debate of D2 v D3 seemed inconclusive when comparing the effects of the hormone 1,25 (OH)D but later research on the activity of the metabolites 25(OH)D2 or D3 show the latter to be the more promising.

      So where does that leave FCLO? Is the taste of this product really worth putting up with if it cannot be demonstrated to be a superior “natural” product?

      • Molly Malone says

        This entire site is worth reading, the cod liver oil and ratfish liver oil is from Norway. It is unfermented.
        http://www.rositarealfoods.com/

        http://www.rositarealfoods.com/cod-liver-oil/2-artisan-extra-virgin-cod-liver-oil

        http://www.ratfishoil.org/oil-in-the-exact-form-it-is-found-in-the-liver
        “Extraction techniques, including so-called fermentation, have been used in the past to render fish liver oils. However, real fish liver oil does not exist in a fermented state, and only achieves this state once the fish dies and is allowed to rot for a prolonged period of time. This is why the pre-industrial process for extracting fish liver oils was described as the ‘rotting process.’

        This process involves putrefaction (although early stages may also be autolytic), a process of disintegration where the livers are left to putrefy (rot) in casks or vats, resulting in the bursting of the walls of the hepatic (liver) cells and the escape of a certain proportion of the oil, which collected on top. This oil was known as “rotted cod oil,” NOT fermented cod oil.”

        “There is a lot of misunderstanding regarding the Vikings and their use of the so-called fermented oils. Actually, the Vikings considered the oil which had undergone MINIMAL fermentation, with a characteristic light yellow colour, and WITHOUT any unpleasant odour or taste, as the best quality oil. This oil is termed “iioa Mediein Tran” or raw medicinal oil.

        The trouble for the Viking fishermen was that very little oil of this quality is obtained. Indeed, it is so little that the Viking fishermen would not take the trouble to collect it separately. Nevertheless, they considered this oil to be therapeutically superior to the heavier and darker coloured oils.”

  3. Molly Malone says

    From what I’ve read, Vitamin A palmitate, Retinyl Palmitate, Retinyl acetate and Retinol Palmitate are all synthetic and toxic, especially to the liver. The Natural form of vitamin A is a mixture of several molecules: retinoic acid, retinal and retinol. Vitamin A is from animal sources, and is fat-soluble. Only the synthetic forms are toxic, even at low doses for some people; the natural food sources of vitamin A are well tolerated and even at even high doses are not dangerous for almost everyone. This is not to say that you can’t over-dose, yes, eat polar bear or seal liver and anyone just might do themselves a mischief since the vitamin A is in the MILLIONS of IUs, but in most of the USA and Europe that is not even possible so it is an extreme case. Further, it reversed by ceasing to eat the offending food.

    Please read here for further info beyond the following quote: http://www.westonaprice.org/health-topics/abcs-of-nutrition/vitamin-a-saga/

    “The Merck Manual describes vitamin-A toxicity in less hysterical terms. Acute vitamin-A poisoning can occur in children after taking a single dose of synthetic vitamin A in the range of 300,000 IU or a daily dosage of 60,000 IU for a few weeks. Two fatalities have been reported from acute vitamin-A poisoning in children, which manifests as increased intracranial pressure and vomiting. For the vast majority, however, recovery after discontinuation is “spontaneous, with no residual damage.”

    In adults, according to the Merck Manual, vitamin-A toxicity has been reported in arctic explorers who developed drowsiness, irritability, headaches and vomiting, with subsequent peeling of the skin, within a few hours of ingesting several million units of vitamin A from polar bear or seal liver. Again, these symptoms cleared up with discontinuation of the vitamin-A rich food. Other than this unusual example, however, only vitamin-A from “megavitamin tablets containing vitamin A. . . when taken for a long time” has induced acute toxicity, that is, 100,000 IU synthetic vitamin-A per day taken for many months.

    Unless you are an arctic explorer, it is virtually impossible to develop vitamin-A toxicity from food. The putative toxic dose of 100,000 IU per day would be contained in 3 tablespoons of high vitamin cod liver oil, 6 tablespoons of regular cod liver oil, two-and-one-half 100-gram servings of duck liver, about three 100-gram servings of beef liver, seven pounds of butter or 309 egg yolks. Even synthetic vitamin A is not toxic when given as a single large dose or in small amounts on a daily basis. Children in impoverished areas of the world are routinely given two 100,000-unit doses of retinol per year for infants and two 200,000-unit doses for children over 12 months.”

    Vitamin-A-rich foods help combat tuberculosis, night-blindness, blindness, reproduction and immune system function, and bone health. In 1904, the Japanese physician M. Mori found that cod liver oil was even more effective than liver in restoring visual function.

    Proper ratios of A:D = 5-8:1 You need 5-8 times more vitamin A as D. Dr. Weston A. Price determined this and it has been supported by the work of others.

    It sometimes becomes a bit tricky trying to do the right thing, and trying to make the best decisions and choices. What used to be common knowledge concerning nutrition and health is no longer so “common.” Because this knowledge and these traditional methods have been lost, we now seem to depend upon science more than ever, making something as simple as a food choice into an unwieldy scientific experiment. Many problems arise when scientists lump all of a certain nutrient, such as A or E, together with all of it’s synthetic counterparts and call it by the same name. This is neither truthful nor accurate – and they may not even be aware of this. It yields useless data leading to false conclusions – all because the scientist(s) did not understand the vast difference between a synthetic and something found in nature, in food. This causes further issues for people when they want information and do not know how to interpret the broken science. What a mess!

    Here’s my advice, not that anyone asked, but it works for me to do one of two or three things, if not all. 1 – find the original researcher and look at that data, experiment and conclusions. Read what the original MD or PhD did and said; and 2 – dig back into history as much as possible and find what once worked and was successful. Apply these 2 simple methods to nutrition and health questions and often you will be able to find the answers without needing to become a PhD in biology or physics. The third thing I do is find people whose knowledge and ethics I respect and read what they have to say, such as this site. Excellent article!

  4. Graeme says

    Can cod liver oil cause skin peeling? And if so, it is temporary?

    I found out I was low in vitamin A, so I starting taking green pasture’s FCLO a couple weeks ago. I noticed that I am having a bit of skin peeling. Doesn’t feel dry, just peeling a bit.

    It’s only in areas of sun exposure – back of arms, forearms mainly. I don’t normally have this, and I can’t think of anything apart from the FCLO that changed.

    I take a couple teaspoons a day. Could this vitamin A be causing the peeling? And if so, is it a good sign (skin repair), or a sign I’m taking too much?

    • Molly Malone says

      Peeling skin is one sign of vitamin A toxicity, so it is possible. A couple of teaspoons a day is actually 5 times more than they recommend, so unless you know that you are deficient, I would stick with the recommended amount, which on my bottle is 2ml. Please keep in mind that 1t = 5ml, so 2t may be too much for you. Perhaps you need less vitamin A than most? Perhaps also, it has to do with a little too much sun?

      The one sure way to find out is to stop taking the FCLO for a few days or a couple of weeks, and then go into the sun and see what happens.
      http://www.westonaprice.org/health-topics/abcs-of-nutrition/vitamin-a-saga/

  5. Lekha Joshi says

    Can i give codliver oil to my 3 year old daughter who gets recurrent respiratory infections and she is very sensitive to every season change, if so what dosage?

    • Molly Malone says

      The short answer is yes, it’s a valuable food. Here’s the long answer from: http://www.westonaprice.org/health-topics/cod-liver-oil-basics-and-recommendations/#brands

      “Our recommended brands of cod liver oil (see below) will provide with the above recommended dosages for cod liver oil about 500-1000 IU vitamin D for children, 1000-2000 IU vitamin D for adults, 2000-4000 IU vitamin D for pregnant and nursing women and up to 9000-18,000 IU for those taking large amounts of cod liver oil to deal with stress and disease.”

      “The high-vitamin fermented cod liver oil is sold as a food so does not contain vitamin levels on the label. However, after numerous tests, the approximate values of A and D have been ascertained at 1900 IU vitamin A per mL and 390 IU vitamin D per mL. Thus 1 teaspoon of high-vitamin fermented cod liver oil contains 9500 IU vitamin A and 1950 IU vitamin D, a ratio of about 5:1.

      Based on these values, the dosage for the high-vitamin fermented cod liver oil is provided as follows:

      Children age 3 months to 12 years: 1/2 teaspoon or 2.5 mL, providing 4650 IU vitamin A and 975 IU vitamin D.
      Children over 12 years and adults: 1 teaspoon or 10 capsules, providing 9500 IU vitamin A and 1950 IU vitamin D.
      Pregnant and nursing women: 2 teaspoons or 20 capsules, providing 19,000 IU vitamin A and 3900 IU vitamin D.

      Please note that the fermented cod liver oil contains many co-factors that may enhance the body’s uptake and usage of vitamins A and D; in fact, many have reported results equivalent to those obtained from high-vitamin cod liver oil with half the recommended dose, that is ¼ teaspoon or 1.25 mL for children age 3 months to 12 years; ½ teaspoon or 5 capsules for children over 12 years and adults; and 1 teaspoon or 10 capsules for pregnant and nursing women.”

  6. Jade says

    I and my family have been taking cinnamon fermented cod liver oil for 5 days now, but stopped today after experiencing headaches, muscle pain, depression and upset stomach. My tooth which is greying due to a injury has stopped hurting which is the only positive thing I have noticed and my family have not noticed anything positive. After researching Stevia (contained in the cinnamon flavoured oil), animal studies have shown health problems with consuming Stevia and so I am putting our symptoms down to that and I am going to return it and replace it with a pure unflavoured oil. Perhaps the reason why some people feel negative effects from Stevia and others do not is just down to different biology and sensitivity, I can feel the burning pain in the side of my head from a couple of minutes on a cellular phone on a call (the pain lasts for hours) whereas many others do not, I guess people who feel effects are like canaries in the coal mine alerting everyone else to the danger.

    • Molly Malone says

      I sympathize, and am similar, often describing myself as a canary in a coal mine as well! I agree with you, I do not use stevia as it causes gastrointestinal distress, and I do not willingly use anything with natural flavors in it. Those natural flavors are anything but natural! Cinnamon can also cause trouble for some as another commenter mentioned; it used to for me but no longer.

      Natural flavors are so called because the law allows it, but all it really means is that it is a cocktail of chemicals that mimic the real thing: they taste or smell (or both) like the extract or oils found in nature, but they are not those things, they are instead a mixture of chemicals made in a lab. The name sounds like the real deal, but it is a lie and is just another one allowed by law.

      I was actually quite surprised that Green Pastures uses any ‘natural’ flavoring in their cod liver oil at all. You can buy the unflavored stuff and add your own organic essential oil such as peppermint (not too much but enough to help) or orange, lemon, lime, grapefruit. Try https://www.mountainroseherbs.com/ for organic essential oils, that’s where I get mine. Click on the Aromatherapy tab at the top, then essential oils.

  7. Sage says

    What if you can’t afford the hefty price tag of nearly $50 a bottle for the Green Pastures? What’s an affordable alternative?

    • Molly Malone says

      The WAPF (Weston A. Price Foundation) has a list here: http://www.westonaprice.org/health-topics/cod-liver-oil-basics-and-recommendations/#brands

      “BEST (Available Online/Mail Order):

      Green Pasture Products: Blue Ice High-Vitamin Fermented Cod Liver Oil, (402) 858-4818, greenpasture.org
      Dr. Ron’s Ultra-Pure: Blue Ice High-Vitamin Fermented Cod Liver Oil, (877) 472-8701, drrons.com
      Radiant Life: Blue Ice High-Vitamin Fermented Cod Liver Oil, (888) 593-8333, 4radiantlife.com
      Natural Health Advocates: Blue Ice High-Vitamin Fermented Cod Liver Oil, 888-257-8775, building-health.com/
      See our list of local chapter leaders and members who sell fermented cod liver oil.

      GOOD (and available in Stores):

      Carlson soft gel Cod Liver Oil Super 1,000 mg capsules
      Nature’s Answer liquid cod liver oil
      NOW double strength Cod Liver Oil capsules
      Sonne’s Cod Liver Oil
      Swanson double strength Cod Liver Oil capsules
      Twin Labs non-emulsified liquid Cod Liver Oil
      Garden of Life Olde World Icelandic Cod Liver Oil”

    • Julielu says

      My understanding is that you can serve animal liver (A) and animal fat products or meat fats (D3, K2). No these are not standardised like vitamins or potentised supplements, but this is traditional and our evolved way to serve the body its needs. NOTE *These products must be sourced from pasture fed animals*!!

      The low cost forms only meet partial needs and the imbalance in cofactors makes them dangerous. FCLO has addressed those issues, so cost is as it is. Your choice is no choice: quality v no quality!

      At second best you take synthetic cheaper alternatives but make sure you are getting what u think, and not getting what you wouldn’t want in these products.

  8. Mrs. Agyei says

    Thank you for your informative articles I take vitamins daily with vitamin a already in it. I have spoken to people 70 and up and they would say they never got sick. I am going try your suggestions only, which was for the cod liver oil you can order frm Green Pasture or Wolf River Naturials.

  9. Asha says

    Whoops, I have Nordic Naturals cod liver oil soft gels… If I take them with a Vit D capsule (I have ones that are 1000 IU), does that help with the Nordics low Vit D?
    Thanks

    • Liz McMillan says

      I do the same thing. Take nordic naturals and supplement with a liquid Vit D/K2. So I’m also hoping this is ok…..

  10. Bellabear says

    I am not opposed to experimenting on myself. I have in fact for many years taken, vitamins, foods,herbs beyond their reccomended dosages. If you read the web long enough, I’m sure you will find a doctor, a vet, or a scientist that will tell you an Apple a day is worthless.. my efforts to find a nstural solution for bellas pain in her rear leg are extensive. Peanut oil, and cod liver oil are next….Vitamin K has been given to her after my ignorance of prednisone became knowledge….I weaned her of prednisone ( she has it) and for over a year purpura has Not visibly recurred. The option to give her prednisone is unacceptable. The bizarre behaviors and obvious pain of prednisone use, are like a dirty bandaid on a shotgun wound. Meanwhile Dr. Vet offers corn as a food for a carnivore. At a nominal fee of course. The irresponsibility, and profit motive has allowed the medical industry to be educated by drug companies. Remember that when you see your doctor or vet……

  11. says

    I would like to start recommending fermented cod liver oil to my patients but I am concerned about the contamination of the fish (mercury and PCBs). Does fermented cod liver oil go through a distillation process to insure it’s safety? If not, how do you know it is not a contaminated fish? Thank you, lindy ford

  12. Julia says

    Though I supporter of Weston Price foundation and intake of Cod liver oil, but toxicity of Vitamin A is not disputable. It’s the most toxic out of all vitamins. If you eat only a couple of ounces of the polar bear liver you will die from Vitamin A intoxication. But it’s still essential vitamin, as any other. So my point of view do not go over 100% of daily dose, especially if you’re pregnant. Because, I was teached that high dose of Vitamin A can cause birth defects, and it was like 10 years ago. And even if you can’t find a study (it’s can be just old enough to exist only in paper format) that’s enough do not take a risk with your developing child.

    • Molly Malone says

      http://www.westonaprice.org/health-topics/cod-liver-oil-basics-and-recommendations/
      “We have pointed out that concerns about vitamin A toxicity are exaggerated. While some forms of synthetic vitamin A found in supplements can be toxic at only moderately high doses, fat-soluble vitamin A naturally found in foods like cod liver oil, liver, and butterfat is safe at up to ten times the doses of water-soluble, solidified and emulsified vitamin A found in some supplements that produce toxicity.(1) Additionally, the vitamin D found in cod liver oil and butterfat from pasture-raised animals protects against vitamin A toxicity, and allows one to consume a much higher amount of vitamin A before it becomes toxic.(1-3) Liver from land mammals is high in vitamin A but low in vitamin D, and should therefore be consumed with other vitamin D-rich foods such as lard or bacon from pasture-raised pigs, egg yolks, and oily fish, or during months in which UV-B light is sufficient to provide one with adequate vitamin D.

      As a general guideline, we recommend the following doses of vitamin A from cod liver oil, along with a nutrient-dense diet that contains other vitamin A-rich foods:

      Children age 3 months to 12 years: A dose of cod liver oil that provides about 5000 IU vitamin A daily, obtained from about 1 teaspoon of regular cod liver oil or ½ teaspoon of high-vitamin cod liver oil.
      Children over 12 years and adults: A maintenance dose of cod liver oil that provides about 10,000 IU vitamin A daily, obtained from 2 teaspoons of regular cod liver oil or 1 teaspoon of high-vitamin cod liver oil.
      Pregnant and nursing women: A dose of cod liver oil that provides about 20,000 IU vitamin A daily, obtained from 4 teaspoons regular cod liver oil or 2 teaspoons high-vitamin cod liver oil.

      Please note that these recommended doses are 2-5 times greater than the U.S. RDA for children, 4 times greater than the U.S. RDA for adults and 8 times greater than the U.S. RDA for pregnant women. The RDA values are based on studies conducted in the general population, which is now recognized to be largely deficient in vitamin D. For a discussion of studies showing that vitamin A consumption up to 30,000 IU per day by pregnant women does not result in a greater risk of birth defects, see Vitamin A for fetal development. This article also describes the vital role played by vitamin A in the development of the fetus. Pregnant women may wish to consult their health practitioner about taking cod liver oil during pregnancy.

      Individuals under stress or wishing to use cod liver oil to treat a disease condition may take much larger doses, even up to doses providing 90,000 IU vitamin A per day, for a period of several weeks.”

      And no, I don’t work for or with the WAPF, though it might look like it; I’m just a member.

  13. Kathy says

    I am confused about which Cod Liver Oil supplement to buy. The link to your recommended list under “here” doesn’t work.
    Thanks for your help,
    Kathy

  14. Fleur says

    All the cod liver oil capsules available in my local shop contain added vitamins A (Retinyl Palmitate) and D, as well as synthetic vitamin E (alpha tocopherol).

    I can understand putting a tiny amount of synthetic vitamin E as a preservative, but they seem to be using nutritionally significant amounts that could upset the natural tocopherol balance.

    And why do they add synthetic vitamins A and D to cod liver oil, which is the richest natural source of both?

    Some brands even contained a lot of other rubbish, like vegetable oils that may or may not be partially hydrogenated.

    I settled in the end for some very expensive Vitamin D3 tablets, which still contained rubbish like sucrose (why do you need sucrose in tablets you are going to swallow with water?)

    Is it possible to buy any vitamin D supplement that doesn’t contain a load of added junk, whether in the form of D3 tablets, or cod liver oil capsules without added vitamins and junk?

    • Molly Malone says

      You can get vitamin D3 in olive oil from vitacost.com, just google search for them. I use it and it works for me. You need to use vitamin A, D3, and K2 all together. I use Life Extension vitamin K. I don’t know if it’s the best, it’s just the best I can afford.

  15. says

    When it comes to the how vitamin D benefits the population in several more ways than is commonly known. The ‘sunshine’ vitamin, as it is sometimes called, is commonly known for its effect on strengthening the bones and joints in the human body by aiding the absorption of calcium. It also helps the body build up immunity. Our bodies can produce vitamin D naturally, if we have enough sun (at least an hour a week). Alternatively, it can be found added to certain foods such as milk, egg yolks, fatty fish, sardines, mackerel, tuna and salmon. These vitamin d rich foods are known to be a great source of omega 3 fatty acids. Cod liver oil capsules are one of the most popular nutrient and Vitamin D dense supplements. I’ve found that adequate vitamin D levels are absolutely essential for a healthy life. I hope it helps you as much as it did for me.

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