The Effect of a Ketogenic Diet on Thyroid Hormone Part 2

ThyroidIn light of the recent discoveries during my n=1 experiment with nutritional ketosis regarding my cholesterol (Part 1, Part 2, Part 3), thyroid hormone (Part 1), and skin rash, I decided to take a break from nutritional ketosis to see what would happen.

We’ve already seen that the addition of carbs back into my diet made my rash go away (it’s been a few months out and still no rash, yay!).

I took another blood test to see if my thyroid hormone levels would change.  We saw on during my first thyroid test that I’m actually considered either hypothyroid or at least sub-clinically hypothyroid.  I hypothesized that:

What is probably going on is the very low level of carbs I’m eating while being in nutritional ketosis is turning off my body’s production and utilization of thyroid hormone in order to preserve energy, and my high cholesterol is just a side effect of this.  

So after eating more carbs I expected my thyroid hormone levels to improve.

Here are the results:

Thyroid Hormone 1

After about 30 days of adding more carbs back into my diet my TSH improved dramatically, and both my Free T4 and Free T3 both jumped up.  This means that I am well out of the hypothyroid range.

The only thing that I’m not quite sure how to explain is why my rT3 also went up accounting for only a minimal improvement in my Free T3 : rT3 ratio.  This may still be a carry over from the changes that occurred in my system while being in ketosis.  It will be interesting to see if this also normalizes on a subsequent lab test.

I also got my cholesterol checked at this time and will report the results on a separate post.

With what you’ve seen so far, any guesses as to what happens with my cholesterol?


42 Responses to The Effect of a Ketogenic Diet on Thyroid Hormone Part 2

  1. Daytona says:

    I also had my thyroid levels tested recently and had similar results, everything is in range except that my T3/rT3 ratio is much too low. I am still looking into how to address it, as I am having hypothyroid symptoms but I don’t believe that adding carbs is the best or only solution. At least in my case, adding carbs isn’t possible regardless. 🙂

    I still need to research it a bit more (which is why I didn’t post my results) but I believe the best resources for thyroid health are Stop the Thyroid Madness ( and the book “Why Do I Still Have Thyroid Symptoms? When My Lab Tests Are Normal”. Both go into great detail on how the thyroid hormones function and interact, why the normal tests and ranges aren’t helpful for addressing your symptoms, etc. Both address what can cause a poor ratio of T3/rT3 and its effect on your body, if you have time, I would love to hear your thoughts after reading either of them.

    • BJJ Caveman says:

      I’ve read through a lot of the thyroidmadness website, and have to say that it’s top notch!

      Will definitely check out that book!

      The interesting thing with me is that I’m completely asymptomatic. Despite having a low T3/rT3 ratio, I feel completely normal, so at this point I’m just messing around to figure out how to optimize these numbers… more for the sake of knowing rather than trying to treat something.

      An important thing to remember is your TSH. Not sure if you’re using the normal range provided by the lab, or the updated normal range that I wrote about on my previous thyroid post.

      • Daytona says:

        It’s great that you don’t have any symptoms, probably there isn’t anything to worry about. Do you think that the LDL and poor T3 ratio are related? While I haven’t looked into it much, seems like that is a common association.

  2. Ashley says:

    Just needed to comment to say that your blog is awesome! I’m a medical doctor who believes understanding n=1 experiments is the future. I’m also currently doing IF and a low-carb high fat diet. And I train BJJ/MMA… So this blog was a pleasant find for me.

    If you don’t mind me asking, what’s your background with the biochem?

  3. Peter says:

    Your n=1 is fascinating, as my recent NMR showed my LDL-P as alarmingly high 2700, but yet all other indicators as very safe, w/ 69 HDL, 67 TG and no metabolic disorders. It seems that often low-carbers get extremely high LDL-P count.

    So that wrecks the notion that consuming dietary cholesterol has small effect (10% or less, according to Attia’s blog) to the body’s cholesterol circulation.

    Perhaps such marker interpretations are only applicable to those eating SAD (high carbers)?

    My bet is since you ate more carbs (and less fat) in past 30 days, your TG would be higher and your LDL-C lower.

    Perhaps you want to eat 20 grams of Brazil nuts just one time, continue that same eating plan that you have been doing for the next 30 days and then do a cholesterol panel?

    Here’s why:

    Keep us posted on your experimentation. Thanks.

    • BJJ Caveman says:

      Thanks for the info on the brazil nuts. If my cholesterol numbers remain screwed up, I may just have to experiment with them.

      I honestly do think that the cholesterol numbers we have now are only applicable to people eating SAD (although there’s been even more controversy regarding this lately and the current treatment using statins).

      More studies need to be done to look at what typical lipid profiles are for people eating low carb or very low carb, especially those in ketosis. We don’t have ANY data about this except for the various n=1 experiments out there (ie Jimmy Moore’s and mine).

      The other interesting thing regarding these sky high cholesterol numbers is that while it’s been fairly well reported among a lot of paleo folks, there seems to be a lot more people out there who report markedly improved and normalized numbers… and there isn’t a clear explanation for why that is … except for genetics.

  4. Richard says:

    Have you had any thoughts regarding the goiteroids in ‘paleo foods’ like kale etc impacting on iodine uptake by the thyroid? Just listened to part 3 of the Chris Keller/Chris Masterjohn podcast ( on this subject, suggesting that it may be an idea to supplement iodine if eating such plant food (but also to ensure adequate selinium intake, e.g. a few Brazil nuts).

    • BJJ Caveman says:

      That’s actually very interesting. At this point I don’t really know enough about it, so it’s something that I’ll definitely have to look into.

  5. Peter says:

    I learned about NMR from Attia’s blog. From him, I read about LDL-P and in particular, Dr. Thomas Dayspring’s analogy that excessive high number of LDL-P particles, are like too many cars on the road. They end up crashing into the guardrails (arterial wall), causing injury and plaques on the artery.

    But it seemed most of his patients cited in had additional risky markers or metabolic disorders that went along w/ their high LDL-P numbers. I have not read one where a patient of his had high LDL-P markers w/o additional risky markers and w/o metabolic disorders. Therefore, I think that Dayspring’s analogy is not applicable to us longer term low-carbers.

    Dr. Rakesh Patel supports your contention that an aberrantly high LDL-P in an otherwise healthy high-fat-low-carb eater is a false positive proxy:

    As for Brazil nuts, Pumed has more clinical studies for its efficacy to improving lipid profiles:

    BTW, having just gotten my order of plain roasted Brazil nuts I will eat 1 nut (appr. 5 grams) daily for my n=1 experiment. It’s rich tasting, kind of bland, lacking the crack-like gateway flavor like peanuts (legume), almonds, and macadamia. Surely Brazil is safer than statin.

  6. Russ says:

    Any update on your latest cholesterol #’s after increased carb intake. My situation seems very similar to yours. I’ve been low carb Paleo for @1 1/2 years with some ketosis at times. My look feel perform better have been off the charts good since going low carb. As a family we went to see a ND a few weeks back for the 1st time and she want to run blood work on both me and my wife. I have never had any done so…sure why not. Expecting good results I was surprised to see total 273, ldl 173, ldl-p 1513, ldl-c 32. However HDL was 84 and Tri 43. Inflammation markers looked good. However my thyroid #’s were very similar to your ketosis thyroid #’s as well. I’m very curios to know how your cholesterol responded to a higher carb intake!!

    • BJJ Caveman says:

      I plan to get new labs in the next few weeks once things settle down. Have some weddings to go to and I anticipate my diet and living going off the rails a bit…. If I check my labs before getting back to my normal routine it’s probably just asking for trouble!

      Stay tuned!

  7. Leo says:

    I just recently got some pretty insane cholesterol levels back from a recent blood test. I have no idea what to make of them. Your blog entries bring up a lot of great sources that might have the answers I’m looking for. My current plan is to heavily limit my saturated fat intake, as well as add omega-3 supplements daily (along with a multivitamin). I’ll have my levels checked in 2 months and pray that things look more normal.

    I created a thread on reddit which you can see here

  8. […] we have less glycogen, other hormones are affected such as our thyroid hormone levels (Parts 1, 2), and our cholesterol can either stay the same, go down, or go way up (Parts 1, 2, 3, 4), among […]

  9. applewine says:

    I’ve developed strange burning and water sensations all over my body after 6 months into an extreme ketogenic diet. I read three books by authors such as Westman, Volek and Phinney on the subject and went all the way. I don’t know the cause for sure, but I suspect diet, nutrition, metabolic. Perhaps thyroid involvement.

    I have been off the ketogenic diet for two months and the symptoms have not gone away yet. These exact same symptoms happened to me two years ago when I was about 6 months into a very low carb diet, but I don’t remember exactly what I was eating and it was not as high fat. The symptoms went away after 6 months or more and stayed away for over a year. However, it was at that point that I researched the ketogenic diet and decided to do it “right” this time with high calories from oils and fat and measure BHB in blood. I was curious about this diet, I’m like that.

    I’ve been thinking of getting my rT3 and T3 checked. I already had my T4 and TSH tested and it was normal, but that was after going off the diet. I very hesitant to go back on any low carb diet. Having a strange neurological problem that you can’t get answers about is very stressful and I don’t want to risk it being caused by low carb in myself. Every body is different and mine may not have a strong thyroid with low carb.

    Nutrition is also possible, who knows. I didn’t take supplements during the ketogenic diet.

    • BJJ Caveman says:

      This is very interesting… and since it’s not something I’ve seen described before, online or in any of the literature I’ve come across I’m not sure what to tell you.

      Could it be coincidental with some other process?

      Micronutrient deficiency? Electrolytes? Something inflammatory or infectious and not diet related at all?

      Might be good to get evaluated by a neurologist just to make sure it’s not something more insidious.

      It shouldn’t be hard to push yourself out of ketosis… and once out of ketosis most ketosis related symptoms should regress. The fact that your symptoms persist is confusing.. and concerning.

  10. […] In an effort to get more iodine in my diet to help with my thyroid health as well as to enjoy a savory snack, I’ve been eating these Kirkland Brand seaweed packets at […]

  11. Kelly says:

    I am so glad I found your site!
    I have Graves Disease – I have had radioactive iodine Treatment so I am now Hypothyroid and take daily T4 and T3. A couple times in the last 6 months I have tried to follow a ketogenic diet and felt rotten. I could tell they were thyroid symptoms – but had not been able to find any coloration between my thyroid and low carb diets.
    Also because of the Graves Disease I follow a gluten free diet so my carbs tend to be “cleaner” – but you can still eat crap on a gluten free diet 🙂
    I will be bookmarking your page a checking in :)I am also a fitness person so performing my “Experiment of One” is my life ling activity.

  12. […] I became hypothyroid (subclinically hypothyroid depending on who you ask).  You can see that after adding carbs back into my diet, my thyroid numbers drastically improved!  So it looks like having some […]

  13. Ninani says:

    I have the same problem. I am 25 yrs old and in ketosis for 6 months now.
    My TSH also level raised in 6 months from 2.0 to 4.2! LDL went from 81 to 158.

    I love ketogenic diet, really. And I am very sorry for having me that kind of problem. I will try to solve it with adding more carbohydrates. Beside very high LDL I am having problem with hair loss which is happening for the first time in my life. So TSH is definately too high.

    To get to the bottom… I am curios about the way you included more carbs into your diet.
    Which carbs did you eat? Bread, pasta, rice or were the carbs more from fruit and veggies?
    What time in day did you eat them (morning, evening)? Seperately from the fats?

    I would be very grateful for the answers. I promise I would come back and report about my carb testing. I will have blood test in about one month.

    • BJJ Caveman says:

      When I intentionally add carbs in my diet I generally try to do it with clean carbs like rice and potatoes… but I do get lenient sometimes and include pastries (I have a pretty powerful sweet tooth)! But most of the time rice and potatoes and rice noodles.

      I generally ate these at lunch or dinner with proteins and fats.

      • Ninani says:

        Thank you very much for your quick respond.
        I think I will first try with adding some more carbs into my diet rather than with one day per week of loading (carb nite).

        • Ninani says:

          After adding more carbs into my diet I’ve improved my TSH levels and also LDL levels.
          TSH dropped from 4,2 to 3,0 and LDL also went back in safe zone.
          My carbs in last 30 days were in average 70 g per a day. Maybe some day 30 and then another day 110 grams.
          I am staying on low carb with little bit more carbs. I ate green bananas, grapefruit, maybe some rice, potato…

          Hope my answer will help someone with similar problems. Very low carb I guess isn’t for everyone :/

          • BJJ Caveman says:

            Thanks so much for sharing!

            Ya… that’s the conclusion I’m arriving at. Very low carb all the time isn’t for everyone… and I’m probably one of those people.

          • Ninani says:

            Also thank you for sharing all the information on that blog.
            Without it I would be still eating pure keto and lost all my hair :))
            I don’t know, somehow I didn’t want to believe that even ketogenic diet isn’t that perfect.

          • BJJ Caveman says:

            I know what you mean. At one point I remember being in a little bit of denial, like I’m not doing something right. I really really wanted strict keto to work for me and have all these amazing things happen to me like Jimmy Moore talks about… but unfortunately that’s not the case.

            That’s one of the reasons I started this blog, was to keep me honest with myself and to keep me accountable with all the stuff I’m observing in my body and all the lab tests and what not…

            Glad it’s been able to help you! that’s very gratifying to know.

  14. Geoff Smith says:

    What do we base what normal thyroid numbers should be? Are the base numbers derived from a carb based population. One would think so.
    If we are eating more like our ancestors perhaps our higher numbers from being in ketosis are more correct.
    We are meant to have a slower metabolism to aid us when food is scarce.

    • BJJ Caveman says:

      We base our normal thyroid on the ‘normal’ population… which is essentially the ‘non-sick’ population, which generally follow the standard american diet. As we know, non-sick is not the same as optimally healthy.

      We don’t have any data for the normal range of people who eat a low carb / keto or paleo diet to my knowledge.

      • Geoff Smith says:

        Precisely. The values are based on those eating a high carb diet.
        I have to say now that I have been very low carb for just over 2 years I can not eat very much food at one sitting. Nor do I need to eat much food in a day.
        My work day consists of physical labour easily 6 hours a day and yet I eat less and less and it does not affect my weight or inches.
        This gives me a new perspective on what food requirements our ancestors really had.

  15. […] putting on a little bit more weight, my LDL-C had come down.  This occurred at the same time that my thyroid numbers improved really making me think that one theory made the most sense, at least in my […]

  16. Michelle says:

    Hi. Thanks so much for posting these medical studies for us.

    I have hypothyroidism and have started the Keto diet, and your post was the second result after googling hypothyroidism and Keto. I found the results you got be something very important, and now I will make sure to have my blood checked more often than I was in the past (every 6 months).

    I was a concerned after seeing that your THS, T4, T3 and Free T3 all went up after being back on carbs. I did not realize that being on a low carb diet could affect my levels to such a degree. I will be sure to be tested far more commonly now.

  17. […] 5/9/2013, after almost two months of eating more carbs my TSH came back down and my Free T3 and Free T4 […]

  18. […] Carb Back-Loading and Thyroid Hormone – The BJJ Caveman on The Effect of a Ketogenic Diet on Thyroid Hormone Part 2 […]

  19. Christa says:

    I have a daughter with epilepsy. We are considering the ketogenic doet for her, but my husband also has hypothyroidism. Would the keto diet be good for him. If we make the change, i would hope to change the whole family.

    • BJJ Caveman says:

      You know what? It would really depend on why he’s hypothyroid, how he’s currently being treated for it, etc… so I’m honestly not sure how it will affect your husband.

      My best suggestion is to find a paleo/primal doc you can work with and see how things go.

      If you were interested in figuring it out on your own… one way would be to check your thyroid numbers before going keto, and then check it again maybe 4 weeks after going keto. To see how the numbers change.


      Pay really close attention to how he feels. If he feels lack of energy, cold or any other symptoms of hypothyroidism, then that will indicate how things are going.

      • Peter says:

        Decades ago my thyroid went overactive, got treated w/ radioactive iodine, and became hypo. I took thyroxine daily to maintain the proper level. 4 years ago I switched into low-carb high-fat and it has had no effect to my thyroid hormone level.

        I concur w/ BJJ Cavemen. Get your husband’s condition treated first.

        • BJJ Caveman says:

          I think the case for you might be because all your thyroid hormone is exogenous.

          Since your thyroid hormone is all being provided in pill form, I wouldn’t expect it to change based on diet… it also depends on what form of thyroid you take though.

          If it’s in the form of T3, then it would only depend on your dosage, regardless of diet. If it’s in the form of T4, and you are keto… or hypocaloric, I can imagine some situations when you would have a normal T4, normal TSH, low normal T3, and high RT3, since some people believe that low carb and the lack of insulin prevent the conversion of T4 to T3 and instead shunt it towards RT3.

          But then again, if you’re asymptomatic and feel well, then you’ve got nothing to worry about!

  20. Daniel says:

    In Keto Clarity the author (Jimmy Moore) writes about this and is quoting several expets on the topic.

    Basically, they say that there could be other reasons for reduced thyroid hormon conversation (for example stress and calorie restriction) and that reduced thyroid hormon conversation in ketosis could be normal because less thyroid hormon is required because metabolic processes are more efficient in ketosis.

  21. […] The Effects of a Ketogenic Diet on Thyroid Hormone Part 2 […]

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