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?

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. Kathryn Avatar

    Thanks for this article Katie. I was taking the FCLO with high vitamin butter oil. If I switch to EVCLO should I be taking something with it to get vitamin K?

  2. Gahariet Avatar

    Hi, and thanks for your report. I have a smewhat different question. I purchased a bottle of fermented cod liver oil 5 years ago and haven’t opened it yet. Do you think it’s ok since it’s fermented to start taking it now? Thanks in advance!

  3. Blacky Avatar

    It seems to me that you can take the FCLO and if it sits well with you then carry on, but if it makes you feel sick then stop immediately.

    I have studied these comments and read these studies for many minutes and find that, as is the case with most things, people will either love something or hate something because none of us are the same.

  4. Chris Avatar

    I just read through the report and I have to say that its very petty and unprofessional. Its opinion and assumption based while the test results do not even support the claims. A clean result comes in and her arguement is that it is so rancid that it tests clean. In short, green pastures is not giving up the family recipe, and while I like transparency, I also understand why its a thing to protect the secrets.
    Im not a super fan of green pastures but I have experienced some benefits with some of their products. And I would be one of the first people to believe that a company is scamming or money grabbing from a trend but there is no validity here. I literaly ready the whole report and I dont think there is one page or paragraph where there isnt a personal jab thrown at the product or owner. I give the report zero credit, through I do hope that if there is truth to these allegations, they will get a professional without a vendetta to write the report.

  5. Leanna Avatar

    As a mom who has used FCLO/BO for her kids in the past but is re-researching it, I would love to hear an update on how you’re liking the extra virgin CLO. We are needing the supplement especially for dental health, so I’d love to hear if you’ve noticed any changes in your or your kids’ teeth with the non-fermented oil.

    1. Victor Cozzetto Avatar
      Victor Cozzetto

      Her resignation gives you some great insight into this issue – She is clearly acting on some ulterior motives, as she ONLY referenced the 3 year old discredited report that has been disproved by many scientists over the last few years, and she provides NO science to backup her position. Remember, she is a scientist. Didn’t she do any research on this topic in the last 3 years? There is no hint of such. There are scientific studies posted right on the WAPF that she resigned from. Also on Green Pasture, and by Dr. Masterjohn, Craig Elding, etc. Did she read those? Does she have some comment about them? Some evidence to refute any of them? Anything? No. Smells very fishy to me. She does not allow comments on her site, but I posted the video below in her Facebook a week ago, and nobody there has made any comment.

      From The Health Cloud:
      https://www.youtube.com/watch?v=SVClJ-4wGdY

      It is sad to see, and I simply cannot imagine what would make her take such action. If she was genuinely concerned about the product surely she would have some evidence for us.

      Victor

  6. Ganesh Ruskin Avatar
    Ganesh Ruskin

    You are seriously questioning Daniels report? I don’t understand where your uncertainty comes from. I have read her report and done secondary research confirming it and am as convinced as i need to be too cease purchasing FCLO. If you doubt her research validity can you not afford to send a sample in for at least one test yourself to confirm her findings?
    For the high price of all of their products don’t you think green pastures should provide any EVIDENCE of integrity and not have customers rely entirely on their word?
    I know it’s hard but let’s just come out and admit it, i was douped through Ramiel’s teeth healing book and you were douped through the WAPF or whoever.
    The only difference is that as a blogger maybe you should do a little research in the future before recommending products with magical quantities of vitamins and methods of extraction. I didn’t have to go further then Wikipedia to find that fermenting, or purification add it is more accurately called is an inferior method of oil extraction used to produce industrial grade clo. Did you not look as far as Wikipedia? Just saying…

  7. Brandi Avatar

    Hi! I tried FCLO a few months ago and had a terrible reaction to it. When I Googled my symptoms, it turned out that my reaction was well documented!

  8. Nicole Avatar
    Nicole

    HI, My name is Nicole and yes my opinion has changed since reading your article. Especially as what Kaayla said about it being her opinion that Ramiel and the other man died from the CLO being rancid therefore causing some type of illness. I don’t remember what she said it was. I know when I was taking it I had no problems with my teeth but since then a number of my teeth have decayed. Thanks a lot for all the research you have done Katie. I am sure many people appreciate it especially when people like me don’t have the time. I have 9 children, 7 daughters at home.

  9. julius Avatar
    julius

    why cant ijust get an honest opion between regular cod liver oil and formminted

  10. Georgia Avatar

    Thanks for this blog. I just recently purchased a bottle of fermented cod liver oil and for some reason quite hesistant to use it. I recently listened to an interview with Dr Ron Smidt – naturopathic doctor who basically consumed this oil for quite sometime… although he did consume high dosages – overtime it has some serious health implications and left him nearly dead. He was part of the Weston P foundation… but since reviewing the concerns of rancid oils discontinued the use, and confirms it was due to the rancid oil.
    I really want to believe that it is healthy and has many benefits but with all these reports it leaves me so confused!

  11. Michelle Avatar
    Michelle

    I too had those same feeling about fclo, so I stopped taking it. I tried eating liver regulaly. I tried the virgin clo from thirive i believe, but I could not tolerate the test. My eczema came back and nothing seemed to work. I finally got the fclo again and after four days my eczema is almost gone!

  12. Melissa Avatar

    Hi. I am overwhelmed with all of this info and makes me skeptical in general. Just want to do whats best for my family and worried if i don’t give them the right things and worried that the products I choose will turn out not to be good down the road. I saw a few posts about Krill oil but not much else. Since the jury is out of Cod Liver Oil, please what are your views on Krill oil??

    Thanks

  13. Jessica Avatar

    Hey, Katie!

    Great post, thanks for all the info. I am a health coach and have been using FCLO for my own family as well as recommending it to clients. Naturally, I was concerned about the allegations. I called Green Pastures for more info and they directed me to a few of their blog posts. I was wondering if you have seen these? I thought I would share with you and ask your thoughts. Seems like some clarifying and helpful info. I am also expecting a call back from Dave.

    https://www.greenpasture.org/blog/scientific-analysis-of-dr-jacob-friest/
    https://www.greenpasture.org/blog/report-on-cod-liver-oil/

  14. Christina Avatar
    Christina

    I have been considering taking FCLO/BO for a while now, as I still have the occasional small cavity even after cleaning my diet somewhat. This year I am cutting sugar and researching supplementation and remineralizing tooth products. After reading your testimonial and cautionary articles, I decided to check out Green Pastures’ website to see how they describe their product. Interestingly, I found two specific statements about their fermentation process.

    On the product page for FCLO/BO: “Fermentation is a natural enzymatic and microbial action that releases the oil from the livers.” (Since the fermentation releases the oil from the livers, the livers must be fermented, not just the oil)

    On the fermentation page: “Specifically, our fermented cod liver oil comes from the prolonged soaking of wild cod livers in brine, which allows cod livers to naturally ferment; the oil accumulates on top and is carefully collected.” (Again, the fermentation of the whole liver is clearly stated.)

    It seems they have added more specific information to their website since November. Personally, I feel no qualms about trying their supplement, especially after reading an article from an independent (as far as I could tell) source about the importance of taking vitamin D in concert with vitamins A and K. I hope this helps! Thank you again for your informative articles, and for spreading the truth about how to build strong teeth without cavities!

  15. Bunny Avatar

    Sally Fallon may be related to David Wetzel of Green Pastures…and the plot thickens…

      1. Bunny Avatar

        It was in the comments section of an article I found before seeing the link you posted earlier about Dr Kaayla Daniel being vindicated. I can’t see the link so I will try to repost it.

  16. Donna Avatar

    What about taking sea buckthorn oil instead (one that has both seed oil and oil from berries)? It seems to have a bunch of vitamins and minerals (a and d) and 4 different fatty acids….

    I looked into a company called “Sibu” and they sell Himalayan sea buckthorn- seed and berries and its organic and food grade so I’m just curious if it has similar benefits as cod liver oil?

    Thank you!

  17. Madi Avatar

    Just sharing my experience..I have been taking Green Pastures fermented cod liver oil and butter blend for about 2 years now, along with minerals and homemade toothpaste (fluoride free); I’ve had 4 cavities heal. Within a few days of doing this combination, my tooth sensitivity decreased. I saw that as a sign to continue with this combination. I feel there is definitely an underground movement to get rid of or discredit any foods/supplements that will heal people of any disorders, conditions and diseases.

    Thank you for your blog! I love all your recipes! <3

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