Is Fermented Cod Liver Oil Safe or Rancid?

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Fermented Cod Liver Oil- Safe or Rancid
Wellness Mama » Blog » Health » Is Fermented Cod Liver Oil Safe or Rancid?

I’ve written in depth before about the supplements I personally take, which for a long time included fermented cod liver oil.

If you follow many bloggers in the natural health community, you’ve probably seen the recent drama about the potential quality issues with fermented cod liver oil. I delve into this in depth below but the summary of my personal current opinion on the issue is that:

  1. There is conflicting evidence on the safety of fermented cod liver oil (and more recently even on the safety of any omega-3 supplements) that warrant more research.
  2. Health and nutrition continue to become more and more personalized so what works for me is not likely to work for you and vice versa.
  3. I personally am focusing on getting all nutrients from food whenever possible and with rare exception and am sticking to foods like sardines and other low-mercury fish in place of supplements.

It is important to note that this is strictly my personal opinion and is in no way close to medical advice (nor is any information on this website). As always, I encourage you to do your own research and due diligence on any health related decisions.

FCLO Drama…

Fermented Cod Liver Oil is considered a traditional food that has been recommended by the Weston A. Price Foundation and many real food bloggers (including me) for years. It was even the WAPF recommended brand for use in homemade infant formula and many members take it religiously.

On August 21, 2015, Weston A. Price Foundation Vice President Dr. Kaayla Daniel released a 100+ page report detailing the results of independent lab tests that she had on samples of Green Pastures Fermented Cod Liver Oil and that alleged major issues with the brand, including rancidity, lower levels of nutrients than were claimed, and sourcing issues.

Dr. Daniel’s report claims that FCLO is not actually fermented, is rancid, putrid, and adulterated with other (cheaper) oils. It also alleges that there are lower levels of fat soluble nutrients in FCLO than claimed and that the oil isn’t even from cod. Serious claims from a well-respected person in the real food community.

Understandably, this has left many people in the real food community reeling and looking for answers. I’ve gotten many emails, comments, and social media messages in the last few days asking what my take on the subject is, and have spent a lot of time researching this myself.

Below is my personal opinion and research on this issue based on the information available right now. I will continue to update this post as more information is revealed.

My hope is that no matter the outcome of further research and study about fermented cod liver oil, the real food community will take this as a lesson in the importance of verifying the quality of supplements and use this as an opportunity to improve the real food movement, rather than to divide the community.

Is Fermented Cod Liver Oil Safe or Rancid?

In short… I don’t know.

Based on the information available from both sides, I don’t think it is possible for anyone (short of Green Pastures, the company producing the fermented cod liver oil in question) to know the answers to all of the questions that many people are asking right now. At the same time, there are some holes in the report from Dr. Daniels and some potential financial ties that have come to light that call her motivation into question.

When our family first started taking fermented cod liver oil years ago, I did a lot of research on the company and on cod liver oil in general (as anyone should do before taking fat soluble vitamins regularly). The only lab reports I was able to find at the time were from Green Pastures and they showed no rancidity in the fermented cod liver oil and verified that FCLO did contain the fat soluble vitamins it was known for.

The recent report from Dr. Daniel calls these tests into question. Her results have the lab company and the party funding the test blurred out, which is somewhat suspect, though I do not think that this necessarily discredits the information in the reports. The report does, however, make some assertions about certain compounds being harmful as a justification for why FCLO is not safe, and some of these claims are not backed by existing science (or are at least controversial).

In the last six months or so, I’ve actually been researching and testing different forms of cod liver oil after readers have inquired about different brands and reported issues they’ve had with FCLO.

My Experience

Our family has seen benefits from taking fermented cod liver oil over the years, including reversal of tooth decay. I’ve also noticed that my skin is naturally more sun tolerant since taking FCLO, probably from the fat soluble vitamins it contains.

At the same time, there is the possibility that the quality of Green Pastures FCLO has changed since I researched it years ago, or that more recent lab testing has been able to reveal problems that were undetectable years ago.

Fermented Cod Liver Oil: The Claims

FCLO is Not Fermented:

There may be some truth to this claim. I’ve talked before about the importance of fermented foods for health, and why the naturally created beneficial bacteria in fermented foods are so important.

The red flag that Daniels explains is that oil cannot ferment. The process of fermentation requires the presence of a carbohydrate as the food for the fermentation process. Many people (including me) assumed that an unnamed carbohydrate was used for the fermentation process but was removed by the process so it was not listed on the ingredients or that the livers themselves were fermented and not the oil (as an oil can’t ferment without another ingredient).

Green Pastures owner Dave Wetzel has been less than transparent about this fermentation process, though supposedly he has brought several WAPF members and high profile bloggers to his facility to see the process and verify its quality. (I have never been to the facility and have no firsthand knowledge of this process, so I have to rely on Dave’s explanation of his process).

This is one area that I hope we see more detail on from Green Pastures and from independent sources in the future. For now, the debate about the process used and what part of the process actually requires fermentation does not necessarily mean that the final product is not high quality, but it does raise some interesting questions to explore.

FCLO is Rancid:

Fats and oils cannot ferment without carbohydrates, so what happens when they are exposed to the conditions of fermentation? In short, they go rancid.

This is the basis for the claims in the new report. The independent lab results from Dr. Daniel show several biomarkers of rancidity in the samples tested (these were not present in the reports I found in my initial research).

In Daniel’s tests, peroxide, free fatty acids and other biomarkers of rancidity were found. I was unable to find clear answers directly from Green Pastures, though I found several older articles and interviews in which Dave states that his product does not contain these biomarkers or that the substances are not harmful. Again, more research is needed from independent sources on this.

Low Levels of Vitamins:

Another claim in the reports is that FCLO contains less fat soluble vitamins than claimed and that the Vitamin D is in the form of D2 and not D3.

The common consensus among medical experts is that D3 is the preferred form, though Green Pastures claims that D2 is equally safe and effective. To be fair, all forms of cod liver oil contain higher levels of D2 and this does not necessarily raise a red flag, but again, more research is needed.

Also, Green Pastures has never made claims, to my knowledge, about the levels of nutrients in their products, carefully explaining that they are a food product and that levels can change.

Not Actually Cod:

The report further claimed that the DNA tests on Green Pastures products showed that the livers used were from Alaskan Polluck, not cod. This seems to be partially an issue of understanding of fish species and families, since:

The Alaska pollock or walleye pollock (Gadus chalcogrammus, formerly Theragra chalcogramma) is a marine fish species of the cod family Gadidae. Alaska pollock is a semipelagic schooling fish widely distributed in the North Pacific with largest concentrations found in the eastern Bering Sea.

After hours of research, I could not find any definitive answer directly from Green Pastures about the origin or species of the fish they use. The closest I could find was Dave’s vague answer from his own FAQs:

Ok, The question arises on the topic of location of the fish. The fish school in the northern, cold waters around the Arctic Ocean. They do not have a nationality and a fish can school for a 1000+ miles in its life. So the relevance of the specific spot the fish is cleaned is not relevant to the discussion, ‘is the fish safe to consume’.

Red Flags from the Report

While Kaayla’s report certainly raises some concerns about FCLO, it also raises some concerns about its own validity. For instance:

  • The labs used for the testing and who paid for the independent testing is not disclosed. This isn’t necessarily a red flag on its own, but given the rumored history of drama within the WAPF organization, I think it deserves further investigation. Given how much heated press this report has generated, I can certainly understand the potential desire of a donor to remain anonymous in the report,  but it does raise a red flag.
  • Though I have no firsthand experience with any of the board members of WAPF, including Sally Fallon or Dr. Daniel, reports of internal drama run rampant in the real food community. In fact, I avoided joining the WAPF for years partially because of these claims. We have not heard an official response from WAPF or Green Pastures yet, and I think that thoroughly evaluating both sides will be an important step for any of us looking to understand the long term validity of these claims.
  • The one funding source that Kaayla mentions in the report, Dr. Ron Schmid ND, has a long and somewhat dramatic history with FCLO. He reportedly took (really large doses- above the recommended amount) of regular cod liver oil and then fermented cod liver oil for decades and attributes them to his severe heart disease. He has also stated publicly that he attributes his miraculous recovery from heart disease with discontinuing taking FCLO. Not exactly an unbiased source. Again, this does not discredit the information, but does raise some additional questions.
  • While Daniels lists sources for many of her claims, she doesn’t list her sources for many of her quotes. In fact, while she says she talked to many experts (including “top university professors, scientists, researchers, lab managers, doctors and other health care practitioners”), these sources are unnamed for many of her more serious allegations. Obviously, these claims would carry much more weight if they were substantiated and sourced.
  • It also raised a red flag for me that Daniel has a call to action for her own services in the report, saying: “Finally, if you think you have health challenges related to FCLO consumption, share your story with friends, colleagues . . . and me. If you think you’ve been harmed, I would like to offer you a FREE mini appointment by phone or face-to- face on Skype. To share your story or to make your appointment, contact me at ***********@earthlink.net.” I can understand her desire to help others if she truly feels that FCLO is harmful, but a report making these allegations does not seem like the appropriate place to make this offer. Again, not a reason to discredit the report, but a red flag.
  • Emerging information has also revealed some potential political ties from the new organization Dr. Daniels founded after leaving/being forced out of WAPF and the makers of the Extra Virgin Cod Liver Oil product she recommends. In other words, the company she recommends as an alternative to FCLO is a sponsor of her new organization so she may have a bias here. Additionally, there is a lot of information floating around about potential conflict within the old organization hierarchy of WAPF that suggests there may be much more to the story on both sides.

The Bottom Line

Based on the available information at this time, it is extremely difficult or impossible to draw a definitive conclusion on the issue of the quality of Green Pastures FCLO or other CLO products. I think that this whole “scandal” is a symptom of a much bigger problem- the mud slinging between competing companies and emerging attacks on both sides of the fence.

The report brings up some serious points and hints at some possible misleading information from Green Pastures over the years. As a mom who has given FCLO to my own family for years and seen good enough results to share my experience with you, I am extremely angry and disappointed in Green Pastures if any of these claims turn out to be true. At the same time, there are some serious holes in the Dr. Daniel’s report and the potential financial ties to the new company bring up more questions.

I think more research and disclosure is needed from both parties, and like I said, I hope that all of us in the real food community will use this as an opportunity to improve, learn more, and get to the truth, and not as an excuse to argue and divide.

At the end of the day, I have to hope and trust until I see evidence to the contrary that both the founders of Green Pastures and Dr. Daniel are interested in health and serving their communities and continue to evaluate any information as objectively as possible.

At the same time, I don’t think either side is unbiased.

Green Pastures, of course, derives a profit from the sale of their FCLO. Dr Daniel has a rumored history of contention with different parties within WAPF and with Green Pastures as well as potential financial ties to the new EVCLO company. Again, none of these are relevant to the validity of the data in the reports or even necessarily to the motivation of either party, but they do provide a possible motivation for slanting information one way or the other.

At the end of the day, things are rarely what they seem on the surface and my guess is that we will continue to find more from both sides of this story.

What Our Family is Doing

As I mentioned, after many reader questions, I have been researching FCLO and alternative cod liver oil sources for months.

Since there is so much conflicting information on the issue right now, please share any information or research you’ve found in the comments below. Has your opinion of FCLO changed as a result of this report?

Sources

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Katie Wells Avatar

About Katie Wells

Katie Wells, CTNC, MCHC, Founder of Wellness Mama and Co-founder of Wellnesse, has a background in research, journalism, and nutrition. As a mom of six, she turned to research and took health into her own hands to find answers to her health problems. WellnessMama.com is the culmination of her thousands of hours of research and all posts are medically reviewed and verified by the Wellness Mama research team. Katie is also the author of the bestselling books The Wellness Mama Cookbook and The Wellness Mama 5-Step Lifestyle Detox.

Comments

329 responses to “Is Fermented Cod Liver Oil Safe or Rancid?”

  1. Jenna Avatar

    I just wanted to comment on the fact that you noted that oils cannot be fermented, however Coast Salish First Nations have been fermenting Ooligan Grease for centuries, where the actually allow the whole fish to begin decomposing or ripening in a cedar box/canoe and then the render the fat. I wonder if that’s possibly the process that Green Pastures use. Hard to know. I’m also very disappointed in the recent information that came to surface. I’ve been a trusted user of Green Pasture products for a few years now. Maybe the answer is to encourage more processing of Ooligan grease and using that instead….

  2. cindy Avatar

    Hey Katie, thank you for all that you do! You are an inspiration. Back in 2008 (!!!) Dr. Mercola wrote about the problems with the Vit A and Vit D ratios in Cod Liver oil. He actually doesn’t recommend taking Cod Liver Oil at all…unless you are Vit A deficient which is rare in North America.

    https://articles.mercola.com/sites/articles/archive/2008/12/23/important-cod-liver-oil-update.aspx

    There is so much conflicting information about Cod Liver Oil!!!! Thanks so much for taking the time to wade through it all. I look forward to hearing more about the debate on FCLO….I was just about the click “submit order” on the green pastures site, when I hesitated to do one last search on your site and found this article!!! I think i’ll postpone that order for now!!!

  3. Kimiko Avatar

    So Katie, any updates on your vitamin d levels? I’m pregnant right now and just ran across this contrversey. I’ve tried to stay away from the Internet so not to destroy my peace. But I found some people talking about it and decided to look at your opinion. I have been taking FCLO from Green Pastures almost religiously for over 2 years. I’ve experienced no negative side affects only positive ones, the same with my son. My anxiety/depression, tooth issues, and skin issues have cleared considerably since I’ve been taking FCLO and my son’s cavity dissapeared within two weeks of supplementing his diet with FCLO. I don’t give my son supplements everyday as we try to follow a healthy organic balanced diet. We’ve never had any of the burning throat sensations (we take the unflavored capsules paired with butter oil and the cinnamon tingle gel with butter oil) or any of the nausea and vommitting some have complained about. So just curious on any updates as its been a few months. Thanks Wellness Mamma I value your blog and the information you provide.

    1. Wellness Mama Avatar

      My Vitamin D levels are pretty good now (not quite as high as I”d like, but not low). I am still researching the topic and very much still divided on the controversy. On the one hand, much of the evidence about it being harmful is anecdotal from people who didn’t feel like their bodies responded well to it. That is understandable but makes me wonder if it is an issue with fatty acid digestion and not the cod liver oil itself. At the end of the day, I do think that there is a very important individual aspect to all supplements and if it works for you that is more important than the experience of others either way. Like you, I also used it in reversing cavities and have seen the benefits, and I hope we will continue to see more research on both sides so we can all make informed decisions. Congrats on your pregnancy!

      1. Kimiko Avatar

        Thank you for your time Katie!!! I think I’ll finish what I have and then maybe switch it up after I talk with my homeopath.

  4. M. J. Avatar

    That’s what I’m doing, Laura. I had only one fairly new bottle when the brouhaha erupted, but I’m taking it and will likely re-order. I have added a 100 IU Vitamin D3 to my regimen JIC, and I’m using the FCLO every other day instead of every day. I’m 67 yo and blessed with no (known) health issues, so I honestly can’t tell if it offers anything positive; I have no indication of adverse effects after taking it regularly for a few years.

  5. Laura Avatar

    Katie, I noticed Green Pastures released an analysis of their product and response to Dr. Daniel’s allegations about FCLO on their website. I am curious if you saw this, and if so, any thoughts on their response and analysis? I’ve still got 6 bottles of this stuff to take or toss, and I’m inclined to just take it since I have been taking it a long time without issues.

  6. April Avatar

    I’ve been giving my children fermented cod liver oil for years. I personally can’t take it as it makes me sick. I never saw any health benefits in my children and one of them had a vitamin D test and it came back as 31, which is right on the border of being considered low.

    After the report came out, I started doing a lot of research. Personally, I don’t think it’s safe and I refuse to give it to my children anymore. I do believe it’s rancid.

    One interesting thing I noticed is that it smells like it has rosemary in it (I have capsules) but on their website Green Pasture claims that they don’t use any rosemary for preservation. I don’t believe it.

    Dr. Daniel explains why she redacted the names of the laboratories on the reports she posted. Most likely that was part of the agreement, that she couldn’t release the names to the public. I’ve seen it before in other reports and it’s not uncommon at all.

  7. Martha Ayers Avatar
    Martha Ayers

    Hello,
    I was wondering if you are still not taking FCLO. I just ordered 8 bottles of FCLO from green pastures and am considering returning but wanted your opinion first.

  8. Debbie Avatar

    Katie,
    I have a bottle of the Green Pastures Blue Ice Royal Fermented Cod Liver Oil that I can no longer use because it is so rancid. I was using it everyday and stopped for a couple months and it is no longer useable. It was kept in the refrigerator. I am very disappointed with the quality of the oil. I am wondering if anyone else had this problem. Thanks, Debbie

  9. Jacob Friest Avatar
    Jacob Friest

    Hi Katie,

    I appreciate your well written article. I will mention up front that I was approached by David Wetzel to review Dr. Daniel’s article. I currently hold a doctorate in Organic Chemistry and work in the Pharmaceutical industry where I specialize in investigating product complaints, out of spec results during product testing, and product degradation. So it is no surprise to me why David contacted me. However, I am a complete outsider to the natural foods/health community and to be honest did not have much interest in taking on this project. That is until I read Dr. Daniel’s article. As a scientist and the Chair of the Nebraska section of the American Chemical Society I was shocked by Dr. Daniel’s article. I was shocked by what she is presenting as scientific evidence. It should raise some very serious red flags to everyone that the so called lab reports are redacted in her article. By doing so she has eliminated any chance for anyone to independently verify her results. This is one of the most unethical reports I have ever had the displeasure of reading. I would strongly recommend to all of your readers that they give the article a very careful and thorough re-read. Look past the scare tactics and evaluate the data for yourselves and what you will find is a very cleverly word smithed article that provides no supporting evidence for the claims she makes. In fact in many cases 2 out of 3 labs show FCLO to be safe yet she leads the reader rather cleverly to just the opposite conclusion. The only conclusive result she presents is for Acid value. However, acid value is not selective for fatty acid formation, the product of hydrolytic rancidity. It measures all acids in the product. Since lactic acid as well as other acids are formed during the fermentation of sugar it is expected that the acid value for a fermented product would be high. Either Dr. Daniel is unaware of this or she is deliberately miss leading the public. This is really only one of many examples from her 100+ page article. Give it a re-read, choose one topic so you don’t lose the tree in the forest, and see what you conclude.

    Regards,

    Dr. Friest

    1. Keri Avatar

      Dr. Friest – Are the P-Anisidine values secondary oxidation? It is my understanding it is an accurate test, but there are still some accusations being made about oxidative rancidity.

      Also, what are you thoughts on the surprising Vitamin D results?

      Thanks

  10. Ambra Avatar

    HI Katie,
    I have always been happy with the FCLO but your article has made me put ordering my next bottle on hold. I know you’ve recommended the Rosita Cod Liver Oil but I was wondering if you have any opinions on the Rosita Ratfish Oil?
    Thanks,
    Ambra

  11. Alyse Plumley Avatar
    Alyse Plumley

    What are your suggestions for pregnancy? Does unfermented provide similar benefits, or should I be looking into another alternative?

    1. Victoria Avatar

      Hello Katie,
      I hope you are feeling well these days since you gave us the wonderful news of expecting!! I was wondering about the FERMENTED BUTTER OIL as well. I had understood from many, many comments that the good results from taking the two together it what gives the healing outcome, such as I was told I needed ROOT CANAL on a very back tooth with a crown over it and after taking the GREEN PASTURE BLUE ICE FERMENTED COD LIVER OIL & GREEN PASTURE HIGH VITAMIN BUTTER OIL together for 3 months, the pain went away, as well as clearing up my rosacea. I read where you will NOT GET the healing results unless you TAKE THEM TOGETHER. I must have read over 200 reviews from customers that purchased the exact same GREEN PASTURE PRODUCTS that I have above mentioned here from Amazon. Many said they took the gel, capsules, mixture of both, BUTTER & COD LIVER OIL together but did not get the positive results until they took it IN THE TWO SEPARATE BOTTLES (as I have listed above) and that is the way I took it, and it HEALED MY TOOTH AND ROSACEA. I recently stopped taking them and my tooth has become sensitive again and my skin has become dry again. I’m excited to hear you will keep us updated because I do not know what to take now. Thank you so much for your commitment to help us thrive to be healthy. Take care & HAPPY BABY TIME! <3 Sincerely, Victoria

  12. Craig Avatar

    There is a lot of hearsay and half truth being banded against GP being banded about at the moment. I think much of this has started from the rather unscientific report by Dr. Kaayla, which actually proved nothing. When you look at the facts of fermented cod liver oil, it has done nothing wrong except maybe not appeal to everyones taste (so by this logic, tomatoes are EVIL).

    Have a read of what we actually KNOW about FCLO here: Here’s the latest update on the Green Pastures fermented cod liver oil sitution! https://www.thehealthcloud.co.uk/fermented-cod-liver-oil-facts/

    I’ll still be taking it as I always have done. I just feel sorry that so much hate has come out of so little evidence.

  13. Monica Avatar

    Will the cod liver oil you are now recommending still work for cavities and teeth that are de calcified? I was just about to buy some and am so disappointed. What benefits will the un fermented cod liver oil have in comparison to the fermented one?

  14. Lindsay Avatar

    The holistic doc muscle tested me for this and confirmed rancidity. At the time, this info hadn’t come out, and I was shocked that a company with such a great reputation would have a bad effect on me. Thanks for the article, Wellness Mama!

    1. Victor Cozzetto Avatar
      Victor Cozzetto

      Muscle testing is a great idea. But muscle testing attempts to determine compatibility, and cannot determine the qualities of a product. Sadly, it seems that the FCLO was not a match for you at that time. However, Compatibility can also change over time, as our body chemistry does, so you may test differently in the future. The FCLO is not rancid, but it is not compatible with everyone. Did you muscle test with their skate oil? Just curious.

  15. Jeanmarie Todd Avatar
    Jeanmarie Todd

    Oil doesn’t ferment, but fish livers do. They are fermented to release the oils. This is neither new nor controversial. I urge you to read the letter from the food scientist released by GP. This answered all these questions about cod vs pollock, rancidity, fermentation, etc. As for Kaayla Daniel’s report? My conclusion is, there is no “there” there.

    No food or supplement is necessarily good for everyone. Biochemical individuality tells us that, so the fact that some people have bad reactions to FCLO even though others swear by its healing power is not surprising, or should not be. We all have to do our own research and try things out for ourselves.

    Thanks for being a voice of sanity.

  16. Lily Avatar

    Thanks for the info. I noticed that when I give my son FCLO he gets a lot of congestion so I took some last night and woke up with allergy like symptoms or a cold and I am not allergic to any food and are on a full gaps so I think it’s not good for our bodies. I will stop that immediately.
    I was thinking in taking vitamin d3 and k-2 mk7 in drops. Do you think it’s a good alternative to cod liver oil?
    Thanks in advance.
    Lily

  17. Anna Humberstone Avatar
    Anna Humberstone

    Hi Katie, have you any more thoughts on fclo since the scandal came out? Just about to finish my bottle of green pastures capsules – first one we have had- and wondering whether to buy fclo or regular clo – here in UK, don’t think we can get evclo 🙁
    Thanks for all you posts!

  18. Pavla Avatar

    Hello,

    What do you think about the quality of Norwegian Carlson cod liver oil? Or could anyone here recommend a good and safe cod liver oil available in Europe?

    Thank you 🙂

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