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. Alex Avatar

    Thank you for staying so open & curious about new info, it’s so important, especially when we think we’ve finally got something all figured out!

    I would absolutely love a post on the biomarker tests you recommend (and how you came about getting them done, through a doctor or at home.) I think keeping tabs on biomarkers could be such an invaluable tool but I have no idea how to go about it, how often to do it, etc.

  2. cheryl Avatar

    oops, should have included <42 is preferable for vitamin D 1,25…above that it is inflammatory for sarcoidosis patients and increases risk of bone and vertebral fractures.

  3. cheryl Avatar

    if you have an immune system problem, especially Sarcoidosis, do NOT take cod liver oil or even vitamin D supplements without first having BOTH your vitamin D 25 and vit D 1,25 level checked. For sarcoid pts, 42 to 46 is considered the highest of normal and <42 would be best.

    Thank you –only trying to avoid a problem in a subset of people. 😉

  4. Lisa Marie Avatar
    Lisa Marie

    Very good friends of mine have owned and operated a small national herbal company here in Canada. They have been doing business with Green Pastures and it’s owner Dave Wetzel for a very long time and they cringed when I brought up his name once. I don’t want to go into details because it’s not my right to say but after hearing everything they shared with me I stopped buying his product and my friends wouldn’t buy his product either because they simply dont trust him. It’s such a shame. I was so shocked and disappointing to hear everything they had to say.

    I say it’s time we start looking for a new source. Glad this article was published. Great work as always Katie 🙂

    1. I-Ju Lin Avatar

      Thanks for the links. They are very helpful. I found another website from a comment through your link providing a lot of insight on this issue, which is https://www.thehealthyhomeeconomist.com/response-to-dr-daniels-report-on-fermented-cod-liver-oil/. Now I am pretty sure it’s Dr. Daniel’s propaganda to put GP and Dave in crisis situation. I believe they will get vindicated. I am now more thankful and respectful for all their efforts to provide such nutrition-dense food convenient for us in standing firm against the degradation of the entire food industry, which use various chemical and nutrient-depriving process, flavour-disguising and synthetic vitamin additives for profits and no concerns for human beings’ wellness.
      I will continue to use their FCLO/BO blend and give to my kids. After taking just half teaspoon per day not even everyday (depending on our food that day) for two months, my daughter’s recent dental appointment showed the first time no cavity at all on X-ray. I definitely need to give some credits to their products if not all.
      Here I want to give my token on how to take fish oil and any oil supplement. Don’t take it in an empty stomach. It’s best to take it with or after food at the meal time. The reason is oil and fat would signal bile stored in gall bladder to be released into the first part of your intestine, which may cause cramps, reflux, and nausea when not enough food is mixing with the digestive juice. Also, taking a small amount at a time is better. If your body cannot produce fast enough the bile salts, some serious reactions may occur in order to purge the oil out.

      1. M. J. Avatar

        Excellent advice in your last paragraph! I’ve always known to take *most* supplements with food unless otherwise noted, but you explained the *why* that might explain why some people don’t tolerate the FCLO well. Thank you!

      2. Stacie Avatar

        I can’t eat food right now…only liquids as I’m in a terrible gastroparesis (stomach paralysis) flare. I don’t think my gallbladder is functioning very well either. I JUST bought FCLO/BO blend and started my first 1/2 tsp dose this morning. Not sure if I’ll be able to continue taking the FCLO/BO if I should be taking it with solid food, which I can’t eat. Bummer!

  5. Renee Avatar

    It is good to hear about this. Whenever I tried to take FCLO I would develop intense rage– it was scary. I asked around, and nobody had an answer. Then I read that one blog where the mom stopped giving her family FCLO, I at least felt less alone. I mean, how could something that is supposed to be a superfood cause me such emotional turmoil at the slightest amount? WAPF has had such a close-knit relationship with Green Pastures that suggesting GP as anything but the gold standard is equal to heresy. To read that there is possibly scientific evidence to back up my body’s instinctual reactions helps me realize I’m not crazy. I look forward to what else you learn and have to share. I appreciate your lack of vitriol in your post. We’ll all have to weed through many differing emotions to find the truth, I suspect.

  6. Richard Nikoley Avatar
    Richard Nikoley

    Great work, Mama!

    In my own case, I got good results from butter oil way back (same as with other sources of K2, primarily teeth and calculus buildup). Couple of years ago I decided I’d try the FCLO/BO blend in caps. I took 2 caps per day.

    Same good results, if not better. I ordered a case of six bottles, so I took them for a good while. Stellar pearly teeth that never need cleaning or even brushing (wooden toothpicks for me :).

    Anyway, I did have a level of frustration with GP and Dave’s obsessive secrecy and mystery. I emailed a simple question: how much BO in each cap, explaining that I would like to be sure I’m getting about the same amount, with the added FCLO. Could NOT get a straight answer. I ask again: well, the BO caps are .5g and the FCLO/BO blend is 1g. I was taking 1-2 BO per day before, and take 1-2 of the blend now? Am I getting the same or nearly the same amount of BO?

    “Most people take more” is the only answer I could get, which I just consider downright smarmy.

    I may use it again periodically in the future, and I really don’t care about the fermented vs rancid issue. Many cultures eat rancid and petrified food as delicacies, and most animals do it all the time. For all we know, some level of spoil has beneficial effects.

    I also don’t care for their religious innuendo in some of their communications, which is personal preference for me, but also, “God made it that way” really isn’t a satisfactory answer since presumably he also made botulinum toxin by the same logic.

    Again, great write up and you’re a great value.

  7. Angela Avatar

    This is a most balanced reporting of the situation that I have seen, but I will say that it is curious that you NOW question whether it is fermented when exactly a year ago, you explain how it was fermented – the livers, not the oil.

    “Fermented cod liver oil is made when cod livers are fermented. This allows the fat soluble vitamins and beneficial oils to separate from the rest of the liver without damaging the fat soluble vitamins (unlike in some methods like heat processing where the vitamins are damaged). This cool temperature fermentation process allows the cod liver oil to maintain its Omega-3, Vitamin D and Vitamin A content.”
    https://wellnessmama.com/59039/fermented-cod-liver-oil-safe/

  8. Michelle Avatar
    Michelle

    Very well said. I have been taking FCLO for years and force feeding it to my kiddos and hubby. Hubby has had fantastic results, but I haven’t had the same results myself… he hasn’t had a cold since we have been taking it. I can’t say the same for myself or the kids. Since this has come out I have been researching other vendors and Rositas seemed to be the top choice, but the Nutrapro as mentioned here in the comments seems good as well. I did run into this article about rat fish oil: https://www.nutraingredients.com/Article/2015/07/02/Norway-warns-on-polluted-fish-oil-supplements.

    Just wanted to share so others were aware. Thanks,
    Michelle

  9. Sage Avatar

    Thank you so much for sharing this information. I’ve been taking it for a couple years now, though not as religiously as I thought I should have. When I began taking my newest bottle a few months ago, I have some stomach and digestion problems. I attributed it to the FCLO rom Green Pastures because I had read another blogger’s concern about the product after something changed in the ownership, if I recall correctly, and that her family began experiencing digestion problems as well. At the time, I took it with a grain of salt, but after the information you have shared, NOW I’m thinking there was a lot more validity to it than I initially thought.
    Where can I read more about the rumored drama within WAPF? The book Cure Tooth Decay is where I learned about Green Pastures. I want to be well informed about all of this information!
    Again, thank you for all you’ve shared. I don’t know where else I would have come across this information, if not from your site.

  10. Jennie Avatar

    Thanks for this information! I’ll be watching here for updates. 🙂

    1. M. J. Avatar

      A lot of informed people follow Katie’s blog! This link from Becky contains further references NHANES studies of the relationship between magnesium deficiency (common today) and Vitamin D deficiency. Wonder if that partially explains the blond surfers who tested deficient in VitD? Single supplements or food ingredients are usually interdependent. The body is a complex machine.

  11. Peggy Huckeba Avatar
    Peggy Huckeba

    Katie, VERY WELL SAID! I have long been impressed with your integrity and transparency. Thank you for your professional coverage of such a sensitive and polarizing topic! All this makes me sad! I feel WAPF works hard to promote the gospel of real health, & I pray this doesn’t hinder that work.
    Thank you for your timely post!

  12. matilda Avatar

    This is so interesting! I have struggled with my guilt for not being able to handle the FCLO. I started taking it during my pregnancy and it was so disgusting to me and I never really took it long enough to see any results. My mom has told me stories that my uncle swore by his cod liver oil to help his joints. After I had my baby, my wrists and knees hurt so badly, so I started taking cod liver oil (cold processed, not fermented) and I would mix it with a little orange juice to get it down. I felt results within 2 days and then I kept taking it all through the winter. I have not been taking it in the summer–mainly just because my joints don’t hurt and it is quite expensive. Thank you for sharing this.

  13. Ian Gregson Avatar
    Ian Gregson

    As a retailer of Green Pastures products, and a WAPF chapter leader, I really appreciate your summary, it’s essentially what I was thinking but put into much more coherent words, and right now I feel pretty stunned by all this! Many thanks.

  14. Lorena Avatar

    Oh Lord… I remember when I first told my husband that I was ordering Green Pastures FCLO. He said “Wow, why is it so expensive?” I explained… I am not currently working so he is the only one bringing money to the house. What am I going to tell him now? This is so frustrating… I still have almost the full bottle I recently ordered….

  15. Jessica Y. Avatar
    Jessica Y.

    Before this report by Dr. Daniels came out, I read the article that the Price-Pottenger foundation put out about what Dr. Price actually did recommend. I did more research and found another company other than Rosita that does cold press their oil – which is something that Dr. Price mentioned. If you read that article, other doctors are mentioned as stating that dark oils should not be consumed and that the oil you do consume should be light in color and not strong tasting – of which the cold pressed oil I got was. So far so good with it. I would love to see your results with your blood work. Smart. I totally should have thought of that! (This is what I ordered about a week before the report came out and I’m so glad I did! https://www.nutraprointl.com/ – I also should say that I asked some questions about the process of their cold pressing and they responded.. “No heat involved, Processed at room temperature followed by Centrifugation and filtration process to make virgin cod liver oil ” and “We don’t use distillation process It is a simple multiplex filtration and slow centrifugation system that does not remove any fatty acids “)

    1. Abby Avatar

      I have been following this whole controversy and wondering why we aren’t talking more about what Dr. Price himself recommended since apparently the work of Dr. Price is where this whole cod liver oil craze originated from. Instead of asking if the FCLO is fermented or rancid, maybe we should be asking if we even WANT it to be fermented. I think the overwhelming answer is NO!! Which begs the question, why does Sally Fallon so strongly recommend only this one brand of cod liver oil? Am I the only one who wonders or is strongly suspicious that she is in some why financially benefiting from the sales of GP FCLO???

      1. Brittany Avatar
        Brittany

        Me too… I could never understand why it was the only “Best” CLO recommended by WAPF (at the time I was researching it…they might have more now). It wasn’t mentioned in Nutrition and Physical Degeneration, and the only ‘studies’ I could find on it were from Green Pastures themselves. I never could bring myself to jump on the bandwagon because something about it just didn’t seem right.

  16. Gary Avatar

    I have been taking FCLO from Green Pastures for years I do get blood work done anually to semi annual bases for Hormones as I get my D3 checked at the same time my doctor said I needed a much higher level than what I had so I am taking 10k IU of a liquid D3 as the pill form of D3 was not absorbable enogh for me to get my blood level high enough so even though I was taking 4ml a day of FCLO my D3 level was still way to low my doctor say for mr to take D3 only, NOT D2 im taking Testotosterone to and wife is also on hormone replacement therapy bioidentical hormones I had high er than normal estrogen levels and am Not sure but I blame that on all the plastics, cause all plastics leech a bad estrogen chemical that blocks testorterone and raises the estrogen level especially after reading indenpendant lab studies on the plastic subject

  17. Catherine Avatar
    Catherine

    Interesting article. When stories like this come out, it is difficult to discern who is telling the truth and who isn’t. Our family used to use GP CLO–before the fermented version came out. We loved it, and felt better when taking it. Then finances got tight and we had to make some difficult choices, such as buy food or CLO. Naturally, we bought food. When finances changed again, a couple years ago, we bought some more CLO, but this time, only the fermented form was available. Only two of us could manage to choke it down. And I mean CHOKE! We didn’t feel better, and in fact the fclo seemed to disagree with me. When we finally emptied the bottles we didn’t buy more. I guess it is one of those things that if it works for you, great, continue doing it. It didn’t for us.

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