MTHFR and Thyroid Disorders

Did you know that your genes are affecting your thyroid?

Whether you like it or not, genetic defects are at work in your body, directly or indirectly interfering with thyroid production.  In this enlightening and informative presentation, Dr Lynch and Dr Christianson delve into an area of medicine called ‘methylation’ and ‘nutrigenomics.’

Be sure to inform your healthcare professional about this recording as they will not want to miss out on cutting edge thyroid research.

Full Video Presentation of MTHFR and Thyroid Disorders:



Nutritional Support:
Consider HomocysteX Plus for supporting riboflavin requirements and the MTHFR defect. Be sure to discuss appropriate dose with your physician.

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Duration: Approximately 1 hour and 5 minutes

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Questions? Comments? This making a connection for you? Post below.


39 Responses to “MTHFR and Thyroid Disorders”

  1. Jeremy Fischer July 23, 2013 at 11:50 pm # Reply

    In regards to thyroid disease and prevalence of MTHFR SNP’s, according to the evidence you presented in the talk, it appears that the prevalence of MTHFR SNP’s in thyroid conditions is similar to that of the general population, thus I wouldn’t say there would be a connection of causality evident between the two. Would you agree?

    • Dr Ben July 24, 2013 at 6:31 am # Reply

      Jeremy –

      Thyroid disorders do not cause the MTHFR defect – that is a genetic issue.

      However, thyroid disorders do affect how the MTHFR enzyme functions.

      If one is hypothyroid, and thyroxin levels are low, combined with low riboflavin status, then the MTHFR enzyme will function more slowly even if there is no MTHFR mutation/defect.

      • Glenn July 30, 2013 at 12:51 am # Reply


        I believe what Jeremy was pointing at, is that the prevalence of e.g. CT in people with Grave’s is just somewhat higher or similar to that of CT in the general population, so the question then is if that difference is statistically significant to suggest a connection with having CT and getting Grave’s or Hashimoto’s?

        And when Dr. Christianson ask at 30:00 “Would I read this correctly to think that the hashimoto’s severe group and the hashimoto’s mild group would be separate, so you would combine those percentages for the total of hashimoto’s?”, you confirm his assumption. I believe there is a misunderstanding here, since the total is summarized vertically to total hundred percent, not horizontally..?

        Just trying to clear up any misunderstandings and make it more understandably for anyone watching, me included :)

        Thanks for all the continued great information!

        • Dr Ben July 30, 2013 at 6:05 pm # Reply

          Hi Glenn –

          You are correct – should be vertical combining of percentages – not horizontal. When flying through a webinar, I sometimes make mistakes ;)

          Also – with this chart – the key point to take home is the prevalence of MTHFR in those with thyroid disorders. It is not to ‘see’ how much worse one can get with MTHFR and thyroid disorders in combination – however, that is a concern.

          Keep in mind also that this study was done in Japan – not in the USA. I’d like to see a similar study done in USA as we tend to not eat as well as the Japanese and our iodine levels are much lower – along with fish consumption, etc.

          • Glenn July 30, 2013 at 11:30 pm #

            Thank you for the quick reply.

            Yes, you’re really blasting through a lot of great information on those webinars, so I totally understand that some mistakes will happen. Time also limits you from going into very deep detail on everything, which can also make things unclear or open for misinterperation, so just wanted to clarify that point.

            Yes I was a bit unsure if the point of the chart was to show that the prevalence of MTHFR in these disorders are higher than the general population, so as to show a correlation of potentially increased risk of getting them given that you have an MTHFR mutation, or to show that people with MTHFR also have these disorders and that the consequence of such a combination might give even worse symptoms..

            Yup, always more relevant the closer the study is to the person and environment you want to use the research for – I’d like some more studies in Norway ;)

            Thanks again for all the good information and keep up the great work!

  2. Jennifer R July 24, 2013 at 1:05 am # Reply

    Is there a way to view with the slides? It’s hard to follow without them. I would appreciate it!! Thanks!!

    • Dr Ben July 24, 2013 at 6:31 am # Reply

      Jennifer –

      Full video is up now ;)

  3. Alicia Hopkins July 26, 2013 at 12:08 am # Reply

    I’ve been on Deplin I have the MTHFR mutation. I’ve had two PE’s and DVT. I just started Ribloflavin but it doesn’t make sense taking it. I tried regular folic acid but never could get enough then I’m on methotrexate for RA and my doctor said I needed more folic acid that DEplin wasn’t enough.

    • Dr Ben July 26, 2013 at 1:53 am # Reply

      Alicia –

      What do you mean ‘it doesn’t make sense taking riboflavin’?

  4. Ann Fm July 26, 2013 at 1:53 am # Reply

    Hi Dr. Ben,

    First, thank you for all your informative research. I have watched your videos, read your blogs, and feel much more educated about MTHFR defects. You are helping so many, thank you! I am a 38 year old female and I am heterozygous A1298C. I have had fibromyalgia and chronic fatigue syndrome for 17 years (basically self-treated) – ranging from bed ridden to functional. In March of this year, I was also diagnosed with Hashimoto’s and I am taking a small dose of Armour. I am blessed to have found a very knowledgeable Dr. who is very familiar with your work and Dr. Yasko’s work. I just started seeing her this year and she immediately tested me for MTHFR. (I also have spent a significant amount of time reading and viewing Dr. Richard Van Konynenburg’s work.)

    I have issue with your most recent statements saying that research is showing that heterozygous A1298C is showing no real significance. What research is this? Were there studies done? Were the studies done on ill patients or well patients? Can you site them for me?

    My doctor says that in her practice some of her most non-functional, ill patients are heterozygous A1298C. I would fall into this category. I also have responded badly to the beginnings of a MTHFR protocol – specifically the Metafolin. (We started on a combo of 1000mcg of methylcobalamin and 800 mcg of Metafolin as L-5-methyltetrahydrofolate, along with methylcobalamin (.2ml of 12.5mg/ml) self injections. That stirred everything up in a hurry and landed me on my back for a month. Now, I am on 1mg of methylcobalamin w/o the Metafolin and I am still doing the injections and I am tolerating it much better, but still not feeling well.)

    So, we are backing up and my Dr. is now checking for more mutations, including CBS and looking for heavy metal detoxing as well as candida. We waiting on results of a 23andme test, a urine heavy metal test, a blood heavy metal test, and a stool test. She thinks the fact that I reacted to Metafolin so significantly, that we are headed in the right direction. We struck a nerve, so to speak. Perhaps, MTHFR defects are not the ONLY problem causing my illness, but I truly believe it is playing a significant role and I am thrilled to have started down this path. I am hopeful. I would more hopeful if I could find success stories on the internet of people who have improved from fibromyalgia and cfs/me after having found a MTHFR diagnosis. Perhaps a page on your website of a collection of success stories from all kind of ailments would benefit/encourage patients who are newly diagnosed.

    I find this new research about the thyroid quite fascinating, but I wonder what that really means. If methyl defects, play into the role and function of the thyroid. Would treating the methyl defects ultimately lead to a better functioning thyroid? Could it FIX the thyroid?

    Would love your opinion on that and would love to know about the heterozygeous A1298C research. I, for now, am refusing to believe that finding my MTHFR defect has no significance.

    Thanks again, Dr. Ben!


    • Dr Ben July 26, 2013 at 2:57 am # Reply

      Ann –

      There are many articles citing that A1298C MTHFR is not much of a factor – and there are also some that say it is – but not many.

      It is best to evaluate more than one gene which is why I have been recommending 23andMe Test lately along with running the MTHFR Support Report.

      One may find improvement still by supporting the MTHFR pathways because of reduced methylation. Reduced methylation has many causes – thus – when supporting it – many will feel better.

      You can review research at – that is where I get all of mine.

      Again – you will find some studies saying A1298C is a factor – but when you look at how the MTHFR gene functions – the 1298 variant is not much of an issue.

      This is my current stance as of now – it may change – but as of now – I think 1298 is only an issue if it is combined with a 677 MTHFR variant.

      • Ann F July 26, 2013 at 4:02 am # Reply

        Ah, well that’s disappointing. I guess I’ll wait to see what the 23andme test results have to say.

        Fibromyalgia and CFS/ME are syndromes that don’t offer a lot of hope, so I was “hoping” that this bit of information about myself was going to lead me on a path to wellness. I suppose it still could. I will pursue it until I hit a dead end…

        Thanks for the insight.

        • Dr Ben July 26, 2013 at 4:13 am # Reply

          Ann –

          It should not be disappointing at all. It should be enlightening.

          One should not put all their eggs into the MTHFR basket. It doesn’t work that way. You have 10’s of 1,000’s of genes in your body. You have to look at many of them and how they interact.

          No doctor should look at just one gene anymore.

          • Kelly July 31, 2013 at 3:23 am #

            I really appreciate your work Dr. Lynch, but I’m a little troubled by the fact that you refer to some of these genes as ‘defects’ or ‘mutations’, while also talking about how common they are and how one can be perfectly health and still have these ‘mutations’.

            It’s my understanding that many of these are actually quite normal variants, and the the issues are those of genetic EXPRESSION, which depends on many other factors, like heavy metals, pesticide or other environmental exposures (as in Parkinson’s) which causes the genes to ‘express’ themselves in different fashions.

            Or do I have this all backwards?

        • Kelley October 31, 2013 at 1:45 am # Reply

          Ann- do not lose hope. A year ago I was in your same spot. I got off gluten and dairy and a bunch of other foods I didn’t even know I was sensitive to. You have to give it at least a couple of months COMPLETELY off gluten to see how you respond (even if you have tested negative for Celiac).You need to go online and look at all the things that contain hidden gluten. It’s a little bit of a pain being off gluten and other foods I liked, but it is WELL worth it.I have my life back.
          You should also have a sleep study done, if you haven’t already, to make sure that you are going into deep stages of sleep.

    • Nancy December 6, 2013 at 3:24 am # Reply


      Just a thought. The fact that you have both Hashi’s and Fibro/CFS makes me wonder whether you have ever been tested for Lyme/tick-borne diseases. It might be worthwhile.

  5. Barbara Wilson July 26, 2013 at 4:27 am # Reply

    My husband has been diagnosed with MTHFRC677R and has been taking Metanx for 6 months along with B1 & B2… He recently has been in remission for LDBC Lymphoma, but now has the Hemochromatosis is flaring. The last 3 months he has been steadily losing weight and is down at least 15+ pounds. The question is more about confidence of the combinations are now more or less falling into place? The doctor that he saw diagnosed him can no longer see him due to insurance reason. We are now at a bit of a loss of some decent follow-up in our area of Upper East Tennessee. Any good recommendations for this as well.

  6. CC July 27, 2013 at 8:33 pm # Reply

    Hi Dr. Lynch,
    Wow what an interesting & informative podcast thank you.
    I am a 35 year old female with heterozygous MTHFR 677T status I am also heterozygous for factor V Lieden and have Hashimoto’s. I also have food sensitivities mainly histamine intolerance. I am currently trying to heal my gut through elimination & nutrition. I am at a point where I can start supplementing & would like to take Thorne’s Prenatal. I am nervous about doing the 23 and me. I am so new to all this MTHFR stuff. Just wondering if it’s advisable to start slowly with this prenatal & see how I do?! Any thoughts on histamine intolerance & MTHFR? I so appreciate you time & work. Thank you CC

  7. Brian Skory July 27, 2013 at 8:50 pm # Reply

    Great presentation and findings! This has been a good complement to my recent deep-dive into Dr. Brownstein’s thyroid research. One point I wanted to clarify, however, regards the slide “MTHFR in AI Thyroid Disorders.” Dr. Christianson noted that in the Hashimoto’s Disease column that Severe was 48.7% CT and Mild was 50.9% CT indicating that nearly 100% (99.6%) of Hashimoto’s patients were CT. If I’m reading the data correctly, what is actually being demonstrated is that for Severe Hashimoto’s an N=18 showed 48.7% CT and for Mild an N=28 showed 50.9% CT, thus indicating a rate of incidence concurrent with what is normally found in the US (approx. 50% CT). Am I reading that correctly?

  8. Tami July 29, 2013 at 2:39 am # Reply

    Is it possible to get a copy of your power point presentation without gray boxes blocking out the studies? This is FASCINATING!!!!


  9. Izabella Wentz, PharmD July 29, 2013 at 4:19 am # Reply

    Hello Dr. Lynch,

    Thank you for your work on MTHFR! My questions is regarding your interpretation of the study by Arakawa and colleagues of thyroid patients with Hashimoto’s and Graves. The way I read it, it seemed that the polymorphisms were as common in autoimmune thyroid disease as they were in the normal population.

    Additionally, the authors concluded that the disease severity did not correlate with whether one had this gene variation or not.

    Direct quote from the study:
    “Genotype and allele frequencies of the MTHFR +677C/T and +1298A/C polymorphisms showed no significant differences between healthy controls and patients with AITD; these genotype and allele frequencies did not influence prognosis of AITD.”

    • Fran August 3, 2013 at 9:55 pm # Reply

      Izabella, if Dr Lynch hadn’t eliminated the column giving the P values as n.s. (non-significant), perhaps he wouldn’t have confused the issue so much.

      • Dr Lynch August 4, 2013 at 7:42 pm # Reply

        Fran – you are right. Sorry about that. I had to due to space. It wouldn’t fit otherwise on the slide. This is why I also include the source of the article so you and others may open the full paper.

  10. Karen Griffiths August 3, 2013 at 7:26 am # Reply

    I have been told I have hidden hyperthyroid. Should I be taking something for this? I have
    C677T form of MTHFR gene defect. I have 4 healthy children and in the past I had
    Rheumatoid arthritis and have been told I still have cold rheumatoid arthritis. I am 66 years old and have some arthritis in my right knee. I used to be asthmatic but no longer have problems with it and swim 45 min every day. When blood is needed for testing they have trouble getting any out from my arm and have to tap into a vein in my hand. My doctor recently put me on Metanx. What do you recommend for me and where can I purchase the products you recommend?

  11. Anonymous August 18, 2013 at 3:09 pm # Reply

    Hi Dr. Ben,
    I was 19 weeks pregnant when the u/s showed a variety of skeletal issues… there was no chance of survival for the baby and I had a D&E. It was thanataphoric dysplasia. We had been trying for a year and both are extremely healthy, live on an organic farm, no fertility problems in our family, just mild male factor (low count). Four months later I am four weeks pregnant… my ND tested me and I am a homozygous carrier for MTHFR C677T…. do you think there are connections between the TD and the MTHFR? I have an appt with my ND tomorrow. I am trying not to worry but I find myself wanting every possible genetic test done but the genetiscist says there is nothing to worry about and the TD was completely random and I show no other “red flags”…. Please advise! Thank you.

  12. Donna December 6, 2013 at 3:11 pm # Reply

    Hi Dr. Ben. I just stumbled across a mention of MTHFR yesterday, and I feel like there are bells and whistles going off as I read about it. Could this finally be an explanation for everything that I’ve been going through for the last 20+ years??? I’m currently 47 years old and doing my best to exercise and watch what I eat, but some of my issues seem to be getting worse rather than better.

    My ongoing issues include going hypothyroid after many years of swinging between being hyper- and hypothyroid. It took me a decade or more of occasional, unexplained discomfort followed by a year or more of feeling as if I were going to die while bouncing from doctor to doctor before I found a reference to Dr. Mercola online. He was still seeing patients at the time, so I was able to get in to see him. The first thing that he did was to put me on Armour thyroid based on my stack of blood test results from other doctors. That was like being born into a new body after less than two weeks. Not that I felt completely well again, but I no longer felt like death was imminent. I’m no longer on Armour because all natural supplements were unavailable for several months a few years ago, but we have my dosage of synthroid adjusted pretty well. I found that taking it at night worked a lot better for me than taking it in the morning.

    I also have very high cholesterol (well over 300 without statins, regardless of my diet), as did my mother, who died of a heart attack last year at the age of 88. Both of us tried fish oil supplements along with red yeast rice, which really lowered our cholesterol for a few months, but then the effect wore off, and our cholesterol went back up. I have issues with hypoglycemia when I eat too many carbs, particularly early in the day. I am considered prediabetic with an A1C averaging around 5.7 to 5.9. I have issues with lower leg edema and high blood pressure that come and go. The edema has been pretty bad lately, seeming to get worse after I started spending 20 minutes on the treadmill every morning. I have mild asthma and allergies that seem to come and go. I am sensitive to chemicals and medications to the point where taking 400 mg of Ibuprofen will put me to sleep for several hours.

    I had preeclampsia with my first pregnancy and delivered early (34 and 36 weeks) with my second and third pregnancies. My two C-sections caused me to have a lot of internal scar tissue, which led to a hysterectomy in 2012 because the scar tissue had glued my uterus to the front of my abdomen and was affecting my bladder and bowels. I am on generic synthroid, pravastatin, singulair, and zyrtec, which has me stabilized from the metabolic mess I was a few years ago, but I still feel that I’m just treating symptoms, not the causes of my issues. I also use an albuterol inhaler and HCTZ water pills to help with the asthma and edema as needed.

    My very athletic daughter, who is almost 17, is going through issues with mild asthma that comes and goes as well as a thyroid that swells up periodically for no reason that any doctor can pinpoint. When both hit her at once last year during a basketball game, she almost couldn’t breathe because her airway closed off. She has had dermatographism since she was about 7 or 8 years old. She also has issues with unexplained diarrhea at random times (usually after a large meal), which her father also has issues with. I took her to a pediatric endocrinologist this past summer, but they ran some tests, patted us on the head, and told us to go home because nothing was wrong with her. We have standing orders for bloodwork, so that the next time her thyroid swells up, we can take her somewhere the same day to get blood drawn.

    Where would you recommend that we begin with our doctor? It’s going to be a challenge to go to her with any requests for MTHFR testing for me and my daughter without her thinking that I’ve gone completely crazy. She’s been good about accommodating my wishes for testing and treatment, but this could be something she’s never had to think about. We live in a remote area, and I’m happy to have found a doctor who listens to me when I can tell that something is wrong. We just haven’t been able to hit on any tests that show anything concrete.

    Thank you so much for your help and for all of the information on this web site.

  13. Debra December 8, 2013 at 9:28 am # Reply

    What are the odds of mthfr mutation and factor 5 both being together? Sorry having hard time phrasing my question appropriately

  14. Chantal December 13, 2013 at 9:11 pm # Reply

    Hi Dr Ben
    Have you found any correlation between MTHFR and thyroid resistance?
    I have mercury poisoning and when first tried DMSA my thyroid antibodies went very high,reverse T3 elevated long story but it appears that the DMSA really effected my thyroid and whenever I mobilize mercury,my thyroid resistance gets worse.I am on a very high does T3,with high lab results but not hyper symptoms.For what it is worth I believe it has to do with receptors rather than the thyroid gland.I’m desperately trying to find and answer to this resistance because at some point I may not be able to medicate .

  15. Tina December 17, 2013 at 8:34 pm # Reply

    Dr. Lynch:

    Simple question: are you saying that MTHFR can cause thyroid disorders? How could so many people with thyroid disorders also have MTHFR and one not cause the other? Thanks.

    • Dr Lynch December 18, 2013 at 6:13 am # Reply

      Tina –

      Both ways – hypothyroidism can cause MTHFR downregulation – just like it would be having a snp for the MTHFR gene.

      The MTHFR snp can cause thyroid issues due to lower biopterin recycling which causes decreased tyrosine levels and thus thyroid hormones.

  16. Sue Bennett February 2, 2014 at 6:47 pm # Reply

    I watched your thyroid presentation and the slide that contained the detail information about how MTHFR impacts thyroid was not displayable and you did not go into detail in explanation on this. Could you please create a follow-up post to this one that provides the diagram and describes in detail the impact of MTHFR on thyroid? Thank you!

  17. Angela May 7, 2014 at 4:20 pm # Reply

    I recently learned I am hyperthyroid based on bloodwork when I went to the ER due to a rapid heart beat. We did all the thyroid workup and found nothing. In fact my uptake scan says I hypothyroid even though my labs are showing hyper. TSH 0.01. I had no thyroid antibodies present. We did find that I am compound hetero C677T and A1298C. I also carry a HLA DQ2 A0505 rare celiac gene. Any idea what is going on with the thyroid here? My Dr’s are once again giving me the “there are some things we know and some things we don’t know and you are what we don’t know”. My last homocysteine level was 10.3 a year ago and my thyroid was completely normal then. We will be drawing a homocysteine in the next few weeks.

    • Marilyn December 14, 2014 at 8:02 am # Reply

      Angela, I’m only jumping in because I see there was no answer for your question.

      When they told you that you had hyperthyroid, did they base it on that TSH number or did they test your Free T4 and Free T3? You can’t know you are hyperthyroid without those. I am hypothyroid/Hashimoto’s, but had a lot of rapid and irregular heartbeat, and a lot of anxiety/panic before I was diagnosed. Those symptoms can go with either extreme of thyroid dysfunction.

      Hope you have got things settled.

  18. Julie June 13, 2014 at 7:35 pm # Reply

    Dr. Ben,

    I am homozygous C677T and hypothyroid. Ive been taking Metanx, Armour, Levothyroxine, iodine, adrenal supplements, etc. for a couple of years. I’ve eaten a whole foods organic diet for 8+ years. Completely gluten free for 6 mo. grain free now for a month. I started taking homosystex plus a few weeks ago. I eat greens, nothing processed, avoid many foods due to intolerance, drink RO water, no soda, etc etc. and I have had very little to no improvement. In fact, the past 6 months or so, I have been even more depressed, anxious, and have put on lots of weight despite eating healthy. I also have developed alcohol cravings during the past year or so. My dr. is kind of at a loss. I’m at a loss and I’m so sick of being sick and tired and depressed. Any suggestions? I listened to you on the thyroid summit and it was very overwhelming to me. Please help me if you can!!!

  19. Miranda July 9, 2014 at 11:29 pm # Reply


    I can’t get the video to play. The podcast will run but I’m a better visual learner. Any suggestions?


  20. Mila July 26, 2014 at 12:32 am # Reply

    Julie, Did they test you for Hashimotos? Hashi people don’t tolerate iodine well. That may be the rub. And have you started any methylation protocols?


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