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Let me introduce myself. My name is Mark Sisson. I’m 63 years young. I live and work in Malibu, California. In a past life I was a professional marathoner and triathlete. Now my life goal is to help 100 million people get healthy. I started this blog in 2006 to empower people to take full responsibility for their own health and enjoyment of life by investigating, discussing, and critically rethinking everything we’ve assumed to be true about health and wellness...

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August 23, 2017

Is Keto Bad for the Thyroid?

By Mark Sisson
114 Comments

Sore throat woman on gray backgroundKeto is fantastic, everyone says. It’s a great way to lose weight, improve cognition, and stave off degenerative disease. It may help your performance in the gym and on the track. It could even give Grandpa some respite from Alzheimer’s.

But it’s hell on your thyroid. Right?

Keto detractors and proponents alike often warn that remaining in ketosis will tank your thyroid. The thyroid’s an important gland, exerting major influence over essential systems like fertility, energy, metabolism, body temperature regulation, blood lipids, and general wellness. It controls the metabolic rate of every organ in the body. We want it working well, so this is a major blow to keto—if the criticism holds true. Fortunately, there’s much more to this story.

The Problem with Keto—Thyroid Research

Up till now, the vast majority of studies on the effects of low-carb, high-fat diets on thyroid health have used high-PUFA high-fat diets. Could this confound the results? Yes.

It turns out that linoleic acid suppresses thyroid signaling. See the impact for yourself….

Rats on a corn oil diet convert less T4 to active T3 than rats on a lard diet.

Rats on a safflower oil diet have a more greatly reduced metabolic response to T3 than rats on a beef fat diet.

Rats on a high-PUFA diet have brown fat that’s less responsive to thyroid hormone. Remember, brown fat is the type that generates heat to keep us warm.

Rats on a long-term diet high in soybean oil have terrible body temperature regulation, which thyroid function in large part controls.

The more rapeseed meal (from which PUFA-rich canola oil is derived) you feed turkeys, the worse their thyroid signaling gets and the less meat/eggs they produce.

Heck, back in the 70s, researchers proposed using vegetable oil as a treatment for hyperthyroidism.

This reduced thyroid signaling isn’t a function of all polyunsaturated fats, however. Omega-3 PUFAs, found in seafood, increase thyroid signaling in the liver. Keep eating fish, folks.

What Other Indications Tell Us

Unfortunately, we don’t have any direct studies comparing the effects of PUFA-based and SFA/MUFA-based high fat diets on thyroid function in humans. We do have a few that offer some revealing indications, however.

In 1995, researchers placed healthy young adults on either a low-carb, high-protein diet or on a low-carb, high-PUFA diet. The latter group experienced big drops in T3 levels, though the significance of the change wasn’t explored.

Later, Jeff Volek ran a low-carb, high-fat study in adults using a diet with Primal-ish fatty acid ratios (8% carbs, 61% fat, 30% protein, with 25% calories coming from SFA, 25% from MUFA, and 11% from PUFA). He didn’t directly measure T3, but the high-fat group had normal T4 and lost significant body fat, which is very hard to do if you’re hypothyroid.

Another, much older study pitted the body temperature regulation of low-carb, high-fat (from cream and butter) dieters against that of high-carb, low-fat dieters by exposing both groups to several hours of -20°C exposure under different feeding conditions. After fasting, both groups reduced body temperature by the same amount in response to cold. After eating, things changed. Those who ate the high-fat meal experienced lower drops in body temperature. Since body temperature regulation is controlled by the thyroid, this suggests that 56 days of high-fat (from cream and butter) dieting had a positive effect on thyroid function.

Key Points We Miss about Keto

Yet, the fact remains that many people report disrupted thyroid panels after going keto. Assuming they’re telling the truth (and I see no reason to doubt them), they aren’t chugging soybean oil, they’re eating enough pro-thyroid nutrients like vitamin A, iodine, and selenium, and they aren’t overdoing goitrogens (don’t eat 2 pounds of Brussels sprouts a day).

What else could be happening?

Calorie restriction lowers thyroid hormone. After all, the thyroid acts as barometer of environmental abundance. If things are good and there’s plenty of food coming in, the thyroid will be active, allowing babies to be made, metabolic output to be high, and energy levels to shoot up. If things are bad and food is scarce, the thyroid will down-regulate, limiting fertility, energy, and metabolic output. Calorie restriction tells the body that things are bad and food is scarce, because, well, energy isn’t coming in like before.

Ketogenic diets are excellent at getting people to inadvertently reduce calorie intake. That’s one of their primary benefits, in fact. But if you go too low, you may lower T3.

Weight loss lowers thyroid activity. Irrespective of the diet used, losing weight reduces conversion of T4 into active T3. Weight loss is a common occurrence on a ketogenic diet. For many, it’s the primary goal. If you have weight to lose, it’s going to happen on keto.

You’re trying to train too much and too intensively on keto. When you endure psychological or physiological stress, the body converts T4 into something called reverse T3. Reverse T3 does the opposite of T3—it lowers metabolism and conserves energy, in case things are falling apart around you. If that seems like a disproportional response to doing too much CrossFit without eating carbs, remember that the environmental conditions under which this physiological system evolved featured such stressors as famine, war, and disease.

All that said…

Maybe slightly lower T3 is a feature, not flaw, of ketosis. The longest living creatures on earth tend to have lower levels of T3. Long-living humans often have a genetic predisposition toward lower levels of T3, as if slowing things down staves off aging. If that relationship holds and is causal, perhaps emulating it with dietary means can provide longevity benefits.

You’ll often hear that carbs increase T3. Put another way, the thyroid increases T3 production to deal with the glucose. Carb consumption increases iodine requirements because the thyroid requires more iodine to make more T3 to deal with the carbs.

This doesn’t mean carbs are good or bad for the thyroid. It just means carbs require more T3 to metabolize. That “extra” T3 is intended for glucose metabolism, not necessarily “making you feel awesome.” If anything, a well-constructed and maintained keto diet has the potential to make you more efficient with your thyroid levels. Since you’re not burning excess glucose, you can get away with lower T3 levels without incurring the negative symptoms normally associated with low T3.

It all comes down to how you feel. If you’re “hypothyroid” but feel great, have plenty of energy, have no issues losing weight or maintaining body composition, I’m not worried.

But if you’re shivering all the time, your lipids are skyrocketing, you can’t muster the energy to maintain basic order in your life (let alone exercise or excel), you’re having fertility issues, and you just feel generally awful, that’s a problem.

You’ll know it if keto has tanked your thyroid. It’s difficult to miss. Thyroid panels can help you see, but symptoms are the ultimate arbiter.

Thanks for reading today, everyone. Now I’d love to hear from you. Are you on a ketogenic diet? How’s your thyroid? What feedback, stories and questions do you have? Be well and take care!

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114 Comments on "Is Keto Bad for the Thyroid?"

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Mike Noskov
Mike Noskov
1 month 1 day ago

Great article Mark. Back in Russia, I was always told in winter months: eat some lard before going outside to stay warm. It is a folk knowledge that fat in food helps to not freeze outdoors. Now I understand why!

shasha
shasha
1 month 23 hours ago

Interesting article. I always learn something from these posts, thanks again, Mark.
As usual, I seem to be an outlier. I had a very unpleasant experience a few years ago while trying to lose weight on a keto protocol. I did lose weight (a lot) but as you said, “went around shivering all the time”, had no energy and my cholesterol numbers were not good. I stopped the keto program and went back to what works for me and everything normalized pretty quickly. Everyone is different, eh?

Jenny
30 days 19 hours ago
Me, too! I stubbornly kept working the keto angle WAY too long, inspired by people’s amazing results. I was cold, my hair fall out, I lost my period,… I thought keto would solve blood sugar control issues (sorta prediabetic), so I worked it harder when I didn’t get the results I wanted. But, then I tested for fasting insulin levels and leptin which were VERY low despite my being normal weight, so my body thought it was in starvation. I was hungry all the time, no matter how much fat and protein I ate. Snooping around in literature, I found… Read more »
Sheena Berry
Sheena Berry
28 days 20 hours ago

Hi Jenny, I’d like to know more about what you did to guide your diet change…I’ve been dealing with hair loss and lack of my menstrual cycle for several months and I can’t help but to think it’s a result of my keto woe.

Liver King
1 month 23 hours ago
Perhaps we could learn something from the most ketogenic culture of all time when it comes to thyroid health and its influence on one of the most important markers of health status… fertility!! Weston Price described how a far North Native Indian culture consumed thyroid to ensure the health and survival of their offspring. Here’s an excerpt from Nutrition and Physical Degeneration… “For the Indians of the far North [reinforcement of fertility] was accomplished by supplying special feedings of organs of animals. Among the Indians in the moose country near the Arctic Circle a larger percentage of the children were… Read more »
Leigh Efferion
Leigh Efferion
1 month 21 hours ago

Wow. Interesting- thanks for sharing

Liver King
1 month 19 hours ago

No problem. To state the obvious, I’m biased towards AncestralSupplements.com but Drrons.com also has a good thyroid product and good service!

Tee Dee
Tee Dee
1 month 1 hour ago

Thanks so much for including this info; I just placed my first order with Ancestral Supplements for the Thyroid supps. I eat liver but not often enough (maybe one good feed every 3 weeks) so may try their liver supps with next order. Thx again..

Zoltan
Zoltan
1 month 20 hours ago

Curious, where do you buy grass fed thyroid? I’m totally open to eating offal and other “odd” bits – been known to indulge in delicacies like liver, gizzards, kidneys, tripe, marrow, lungs, pork brain and maybe even turkey testicles at one point – but I cannot just walk into a butcher’s shop and ask for grass fed thyroid.

Kari Dilda
Kari Dilda
1 month 20 hours ago

Drrons.com. He’s associated with WAPF. All kinds of desiccated grass fed organs.

Denise
Denise
1 month 19 hours ago

Thank you Kari – checking his website for sure……

BB1974
BB1974
1 month 19 hours ago

AncestralSupplements.com has the exact same desiccated thyroid as Drrons.com but price is much more reasonable. I swiched to Ancestral Supplements six months ago. Exact same thing. Sill very good results. Different price.

carla
carla
1 month 19 hours ago

I am curious about that too. I do not have the appetite for that kind of thing, but I am willing to use it as a nutritional supplement.

Pierre
Pierre
1 month 23 hours ago

Not sure about the statement that metabolism slows down when you are starving. That doesn’t really square with my fasting results and it doesn’t make sense from an evolutionary standpoint. Seems that slowing down when you need to chase down some food would lead to your extinction.

BLKC
BLKC
1 month 19 hours ago

From what I understand, there is a difference between fasting and starving. Starving is not getting food over many days. Fasting is not eating for a long while, but still getting enough food before and after the fast. Fasting doesn’t drop metabolic rates, but starving does. I think he’s saying that people who are on keto can inadvertently eat too little so intermittent fasting can then turn into starving.

PIerre
PIerre
30 days 21 hours ago

From an evolutionary standpoint it makes no sense for the body to get weaker if it is starving. Of course there is a limit to how long you can go on your fat stores but if you still have fat stores then you still have energy to burn. What I have noticed on 5 day fasts is that I am even more alert and ready to go on the 5th day.

Fittsdawg
29 days 13 hours ago

the biology of the metabolism lowering during starvation is that if food is not available, then you can live much longer on your fat stores with a lower metabolism than you can on a high metabolism, which gives a better chance of surviving until the next successful hunt or harvest.

PIerre
PIerre
26 days 18 hours ago

That is intuitive but incorrect.

carla
carla
1 month 19 hours ago

Fasting is different from starving.

Time Traveler
Time Traveler
1 month 22 hours ago
Great and long due article; thank you Mark! Dr. Ron Rosedale by the way, is very much in support of lower metabolism (furnace) then one that revs at high temperatures. As I disclosed in the past, I have Hashimoto and while most of my calories are from fats and no starch, my thyroid levels are better the ever. It took some fine tuning but I got there and I hope it will stay that way. On strenuous days, I do eat a little carbs and a piece of wild fruit/berries or a 1/4-1/2 tsp black strap molasses (in a narrow… Read more »
Leigh Efferion
Leigh Efferion
1 month 20 hours ago

Hi Time Traveller, I too have Hashimotos & would like to try this way of eating to improve weight, energy & brain fog… what tools did you use to guide your journey in respect to following this protocol? Kindest, Leigh

elle
30 days 17 hours ago

Leigh, I work for Primal Blueprint…if you have hashimotos and want to go primal and then eventually keto, contact me for some free information on this, or buy my book THE PALEO THYROID SOLUTION.

Candace
1 month 20 hours ago

Hi! May I ask if you are male or female? I tend to think that men do better with low carb and keto style diets than women do, although menopausal women also tend to do better with low carb. Just curious….a little context helps compare my experience.

Lorie
Lorie
1 month 20 hours ago

Hi. I would like to chat more with you about what you’re doing. I’ve been nervous to try ketogenic because of Hoshimotos.

Eva
Eva
1 month 16 hours ago

Might want to start out gradual, just eat carbs once per day only and see how you feel, for other meals eat low carb. .

Time Traveler
Time Traveler
1 month 4 hours ago
Hi, sorry for not responding right away as I am at a different time zone. I’ll try to answer everyone best as I can without turning this into an essay and will start by saying that I am a male. I got relief after having wacky thyroid values for the last 10 years. Now my TSH is just above the minimum and my free T4 & free T3 levels are near ideal when at fast, which mean that they are slightly higher or perfect otherwise. It’s also imported to get your blood drawn prior to taking your daily medication. The… Read more »
Grokesque
Grokesque
29 days 8 hours ago

Hi Time Traveller. Just a quick question about Cynomel as I am in France and cannot get prescribed anything but Synthyroid for Graves disease – are you in France and if so did you go through your doctor to get it. I am so fed up of hearing about NDT which isn’t available here and am struggling even though I feel so much better on keto. Thanks for any help.

Time Traveler
Time Traveler
19 days 8 hours ago

sorry for the typo….it’s weird that you can’t get…

Time Traveler
Time Traveler
18 days 4 hours ago
In case you’ve been wondering… I sent you a reply and it showed waiting approval…this is my 3rd attempt to get my reply published after which I am ready to throw the towel and not bother anymore… Anyway, I replied earlier by saying that it odd not to be able to get a medication that’s manufactured in your own country. You can look up Avantis Sanofi’s email and inquire who in France sell Cynomel [www.sanofi.fr], or you can call the company at +33 1 57632323. Another option is to take a short trip to Belgium, walk into a Pharmacy and… Read more »
grokesque
grokesque
17 days 22 hours ago

Hi Time Traveler – thanks so much for the several replies. I have an appointment soon so I will indeed try for a GP/Endo prescription first, armed with the knowledge that it is available! Then, if all else fails I will pop over the ‘border’ to Belgium! Thank you for your detailed replies – you have no idea how much I appreciate them!

Time Traveler
Time Traveler
17 days 9 hours ago

Grokesque, you’re very welcome. I would love to get a future update on how you did. Best!

Pan
Pan
23 days 3 hours ago

Hi there, TimeTraveler. Thx for the info. For my leg cramps i just increased for a few days my bananas consumption and it worked. Please check “potassium”.

Time Traveler
Time Traveler
19 days 9 hours ago

Hey, I’ve tried potassium to no avail and I try to stay away from bananas (too many carbs) unless they are fairly green. But guess what, I’ve ordered magnesium chloride oil order and have been pain free for a week now (I spray my legs before going to bed and sometimes before I workout) and without supplements at all. Based on the above, I ordered magnesium Chloride Liquid that can be taken orally and that should cover it.

Pan
Pan
17 days 17 hours ago

Thanks for the info. I’ll ckeck it out.

Leigh Efferion
Leigh Efferion
19 days 20 hours ago

Thanks so much for taking the time to answer Time Traveller. Best for the future, Leigh

Casey
Casey
14 days 1 hour ago
Thanks for so much information. About your leg cramps. I have a history of having low iron and one of my symptoms is leg cramping. I experience this even when my blood test shows me in lower half of the “normal range.” When I supplement with iron, this goes away. I don’t use much, but it is the only thing that stops it for me. I also eat mostly red meat and cook in an iron skillet at times, so you’d think this wouldn’t be happening. I think it is related to the fact that I have Celiacs. Anyway, might… Read more »
Time Traveler
Time Traveler
13 days 21 hours ago
Hi Casey, you are welcome and thanks for sharing. Maybe I can trade you some, as my body stores iron — ferritins actually (hopefully less now, as I’ve been donating blood quarterly) due to enzyme deficiency (g6pd). As I wrote nearly a week ago, I am amazed that the spray (life-flo) succeeded where various magnesium supplements failed. 4-5 short bursts on my legs before bed time is all I’ve been doing and it works like magic, consider the low dose. I just received today the ingested version (nutricology) and will try it without the spray. Also, I wouldn’t count too… Read more »
elle
30 days 17 hours ago

Don’t be nervous but you must learn all you can first about thyroid AND keto….I will be posting a KETO-THYROID PODCAST chat with Mark Sisson soon, look out for it on The Primal Blueprint Podcast….we discuss my book THE PALEO THYROID SOLUTION and also talk KETO and THYROID and a bunch of misconceptions around it:-)

Nicole
1 month 22 hours ago

Ah, the big question finally answered! I guess it is worth a shot to see how I feel.

Suzan R
Suzan R
1 month 22 hours ago

I’d like to start into a Keto diet, but I have had all my thyroid numbers tested twice to be sure. Both times I have normal numbers except for high Reverse T3. I have a terrible time losing weight. Not sure if Keto or IF is good or bad for me?

Barefoot girl
Barefoot girl
1 month 21 hours ago

Give it a try– you’ll know!

Quilteresq
Quilteresq
1 month 20 hours ago
High reverse T3 means that you don’t have enough regular T3 to get the job done. It blocks uptake of regular T3, but does zero for your metabolism. This has happened to me a couple of times. The fix is to go on an all T3 regimen for a few weeks to kick out the RT3. So, even though “all your other numbers” are normal, you are really hypo. For the record, I had a huge goiter and “normal” numbers for close to 20 years, along with a fibromyalgia diagnosis. Now I have no fibromyalgia, no goiter and I feel… Read more »
Suzan R
Suzan R
1 month 20 hours ago

Thanks, what is an all T3 regimen?

Suzan R
Suzan R
1 month 20 hours ago

I already eat Paleo.

Quilteresq
Quilteresq
1 month 20 hours ago

Thyroid meds come in three kinds – synthetic, like Synthroid (terrible in my opinion, it’s artificial T4, the inactive form of thyroid hormone that has to convert to T3 to be used), Natural Thyroid, like Armour or Naturthroid, which is desiccated pig thyroid – it has ALL the thyroid hormones. T3 I believe is also synthetic, but it’s the active form of the hormone. The brand I use is Cytomel. It’s used a lot less than the other types. I normally supplement with one a day with my Naturthroid.

Quilteresq
Quilteresq
1 month 20 hours ago

Oh – but when the Reverse T3 goes really high, I use ALL T3 in lieu of Naturthroid.

Suzan R
Suzan R
1 month 20 hours ago

Thanks, I’ll ask my doc about taking Cytomel for a couple of weeks. He’s open to alternative solutions. Do you eat a Keto diet or a Primal diet?

elle
30 days 17 hours ago

You can learn all about Reverse T3 AND T3-only dosing for it in my book THE PALEO THYROID SOLUTION…and I will be posting a KETO-THYROID PODCAST chat with Mark Sisson soon, look out for it on our Primal Blueprint Podcast….we discuss my book THE PALEO THYROID SOLUTION and also talk KETO and THYROID and a bunch of misconceptions around keto and thyroid.. coming in the next 4-6 weeks on our show.

Liver King
1 month 15 hours ago
I’ve harped on this topic before but here’s your answer… Functional ranges of FREE T3 are 3.0 – 4.0 pg/mL. If you’re below 3.0 pg/mL, you might actually be hypothyroid. Would ketosis hurt ya or help ya… Completely depends on why you’re hypothyroid… for instance, if you’re hypothyroid because of stress / cortisol dysfunction, then chances are that your reverse T3 (rT3) has been upregulated thus displacing free T3 (at the cellular level) in an effort to slow you down and get you recovered. Same thing happens when you get sick, or get the flu but with chronic stress, it’s… Read more »
Lorraine Gullett
1 month 7 hours ago
Susan R, I am in your position and tried 5:2 and did lose 2 stone, however I became very ill. I am still seeing Endocrinologist 18 months on. Have been unable to lose weight for years so hoping he will give me some T3 to help me. T3 being your fat burning mine at the bottom of the range. Currently I am doing 16:8 and it’s easier to stick to. I eat clean, cook from scratch, no meat just fish and veg. Organic beetroot juice I hate but drink it as it’s full of iron and other nutrients. Need my… Read more »
Crystal
Crystal
1 month 21 hours ago
I’ve been hypothyroid for 29 years. I’ve been on a ketogenic diet since March of this year, so 5 month now (my version is high protein, moderate fat, low carb – Ketogains diet – 107 grams of protein, 90 grams of fat, 35 grams of carbs only from fruits and veggies per day). My endocrinologist is ecstatic with all of my bloodwork, and for the first time in many, many years my thyroid is completely stabilized. I feel amazing, look amazing, have lost 22 pounds, inflammation is gone, energy has been restored, and all endocrine issue have been stabilized. I… Read more »
Doug
Doug
1 month 20 hours ago

Hi Crystal, just curious, have you tested yourself (by blood or even with urine strips or breathalyzer) to see if you actually are in a ketogentic state? From my understanding high protein will likely keep you out of ketosis. Either way, congrats on your results.

Crystal
Crystal
1 month 20 hours ago

Yes, I have tested (both), and am in a ketogenic state. I believe you’re referring to gluconeogenisis, which is where your body takes “stuff” that is not glucose and turns it into glucose. The studies which have been done have shown that the rate of GNG does not materially change when protein content of the diet is manipulated (or at least the amount of amino acids taken up by the liver). Staying between .8 to 1.0 grams of protein per pound of lean body mass, and under 25 NET carbs per day keeps the body in ketosis.

Indigo
Indigo
1 month 17 hours ago

Thanks for that info, Crystal. That’s where things went wrong for me. I think my protein was too low! I was doing fine on primal/keto till I decided to follow the advice of Nora Gedgaudas and drop my protein to avoid activating mTOR. That’s when my hair started falling out! (AK!!) I’ve since upped my protein again (and up carbs every 3rd day). Hopeful things will improve.

Candace
1 month 20 hours ago

Interesting! Thank you for sharing. Maybe I need to give it a shot for a while and see how things go.

Crystal
Crystal
1 month 19 hours ago

If you do, try out Ketogains. http://www.ketogains.com They also have a Facebook page.

Stefan M
Stefan M
1 month 17 hours ago

Isn’t that around 1400 calories, all added up? That’s quite a hell of a calorie restriction…
Are you doing alright? Have you tried increasing the amount of calories slightly? Felt better or worse if so?

Crystal
Crystal
1 month 17 hours ago

I feel great – sometimes I eat more, sometimes I eat less depending on how hungry I am and how much I’m training. Every body is different, and I don’t require as many calories as most, as my thyroid (over 29 years of being hypo) has slowed my metabolism. I have a ton of energy, wake up before the alarm goes off, and am very active. i run half marathons and weight train 4x/week. 🙂

Stefan
Stefan
1 month 17 hours ago

Certainly, I don’t doubt your energy! I’m sure you’re thriving right now.
I wanted to open up the possibility as consideration, in case you ever feel you need it!

Since we’re all health jeeks in this article, we always want to tinker with our diets, to scavenge each rabbit hole.
It’s very important to maintain a flexible attitude and adapt based on your body’s feedback, I believe! So keep doing what you’re doing if it’s working for you.

Stefan
Stefan
1 month 17 hours ago

Geeks*. Oh gosh.

Elizabeth
1 month 14 hours ago

Wow, Crystal that is awesome! Sounds like a lot of protein but it’s working great for you. Weight loss + improved quality of life is awesome!!!

Debbie Boyer
1 month 14 hours ago

Hi i was hyper for years got i131 2 years ago put on instant 10 lbs now hypo cant lose a pound. Gonna start the keto diet glad to hear some good results.

elle
30 days 17 hours ago

I will be posting a KETO-THYROID PODCAST chat with Mark Sisson soon, look out for it on The Primal Blueprint Podcast….we discuss my book THE PALEO THYROID SOLUTION and also talk KETO and THYROID and a bunch of misconceptions around keto and thyroid.

Crystal
Crystal
30 days 17 hours ago

The Paleo Thyroid Solution was the absolute most helpful thing I’ve ever read regarding my throid health – ever. That book opened my eyes to true diagnosis and healing. I began eating Paleo after I read that book, and then gradually went over to Keto. It’s the best thing I ever did! I’ll look out for that podcast. Thanks.

Thorfinnsson
Thorfinnsson
1 month 21 hours ago

I’ve been eating mostly paleo, mostly keto for a few years now. Never had any issues.

Currently part of the N Equals Many carnivorous diet trial. More than one week in, no issues. For me this eliminates cheat meals at restaurants, sides to my meat/fish, and alcohol.

Should be interesting to see where this goes.

Ashley
Ashley
1 month 21 hours ago
So glad you published an article about Keto & it’s relation to thyroid function! Unfortunately, I have diagnosed Hypothyroidism after a procedure that removed half of my thyroid (before the surgery, I had hyperthyroidism) I take a medication every day called Armour which is made up on crushed & dried pig thyroid. I have to take this every day for the rest of my life. My significant other has experienced much more drastic results from Keto than I have, and I felt like my thyroid function was to blame. I was sticking to my macros religiously & working out daily… Read more »
Jeanette
Jeanette
1 month 20 hours ago

Long time reader! Great HELPFUL article! Thanks!

Angie
1 month 20 hours ago
We’re not keto, but we both have sluggish thyroids. Mine was slow before we hooked onto evolutionary health, but Fiorenzo’s took a turn after he lost quite a lot of weight in the first 6 months of going Primal. He stared coming home from with chilblains on his fingers and toes, which had never happened in 30 years of outdoor work. We’re still trying to work it out, and seem to need that boost from a thyroid stimulant. Interestingly enough, Fi has been practicing Wim Hoff breathing techniques and cold showers for about a year now – with results. Amazing.… Read more »
Liver King
1 month 19 hours ago

Wim Hof method is nothing short of incredible.

elle
30 days 17 hours ago

I will be posting a KETO-THYROID PODCAST chat with Mark Sisson soon, look out for it on The Primal Blueprint Podcast….we discuss my book THE PALEO THYROID SOLUTION and also talk KETO and THYROID and a bunch of misconceptions around keto and thyroid.

Candace
1 month 20 hours ago
Thank you for the article and this perspective. I think that once thyroid dysfunction has already occurred (down regulation for whatever reason) that the body needs more carbohydrates than if the thyroid is functioning properly and someone decides to eat low carb. This has been my experience. I’ve been on a T4/T3 combo for a few years and while I’m not high carb by SAD standards, I’m not low carb by any means. I think I’m a bit insulin resistant, but am too afraid to go back to a low carb style of eating since I’m feeling pretty good and… Read more »
Primal Al
Primal Al
1 month 20 hours ago
Wow, I don’t know if it is related or if my situation exactly fits what Mark means by “disrupted thyroid panels” but I have been eating paleo/primal for the most part and working out for the last 2 years. I lost about 30 pounds over that time frame. The last few times I had regular checkup tests my doctor told me that my TSH was above normal (I think one time it was about 10 and another time about 14). He had me take another test which tested T3 and T4 and they didn’t seem that out of whack so… Read more »
Liver King
1 month 15 hours ago
Some of the most important thyroid markers to evaluate are FREE T3 and reverse T3. Make sure you get these. Here are the functional ranges for thyroid:… – TSH: 1.0 – 2.5 ?IU/mL – Total T4: 6.0 – 11.9 ?g/dL – Free T4: 1.0 – 1.5 ng/dL – Total T3: 100 – 168 ng/dL – Free T3: 3.0 – 4.0 pg/mL – Reverse T3: 14.9 – 24.1 ng/dL – TPO antibodies: 0 – 15 IU/mL – Thyroglobulin antibodies: 0.0 – 0.9 IU/mL If you don’t have any signs of thyroid issues, I wouldn’t worry about it too much. Your TSH… Read more »
elle
30 days 17 hours ago

Primal Al…read my book The Paleo Thyroid Solution or go onto our podcast and search Dr. Foresman – we did a Paleo thyroid podcast and one on hyperthryoidism too :-). I will be posting a KETO-THYROID PODCAST chat with Mark Sisson soon, look out for it on The Primal Blueprint Podcast….we discuss my book THE PALEO THYROID SOLUTION and also talk KETO and THYROID and a bunch of misconceptions around keto and thyroid.

Mike
Mike
1 month 20 hours ago

Great article. Question – I had thyroid cancer 15 years ago, had a thyroidectomy and take a synthetic thyroid supplement daily. Would taking a supplement be any different than what you have described in the article?

Kelly
Kelly
1 month 19 hours ago

I have been eating keto for over a year. All of a sudden my hair is shedding g more than usual with my hypothyroidism, I feel drained all the time. I heard I should be taking supplements but not sure which ones to take to help with energy and hair loss. Overall doing keto to stay healthy not to lose weight.

Liver King
1 month 19 hours ago
THYROID NUTRITION IS ALIGNED WITH [ANCESTRAL NUTRITION] For most of human history, we effortlessly consumed nose-to-tail nutrition that supported our strength, health and happiness. In the modern world, we unknowingly struggle to fulfill our nutritional needs. The nourishing wisdom that allowed our early ancestors to live a vibrant, disease-free life has been tucked away for convenient, cheap, hyperpalatable food-like products. The most common nutrient deficiencies are also implicated with thyroid health. Vitamin A – Look to liver for real, preformed vitamin A (retinol). If you’re not consuming liver (or) desiccated liver, you’re probably deficient. Vitamin D – Get sensible sun… Read more »
HealthyHombre
HealthyHombre
1 month 18 hours ago

LK after reading Lipton’s book I’m now reading You are the Placebo by Joe Dispenza?, amazing book also, similar to BOB but a little more “modernized” take on epigenetics and not quite as much science to grapple with, or at least less cell biology and more in terms of brain function and the power of the mind.

Liver King
1 month 18 hours ago

Missed you my good friend!! Thank you for the recommendation.. I just bought it. Currently reading Splendid Savage but will start afterwards. Thank you!!

Elizabeth Resnick
30 days 23 hours ago

I’m going to have to check that out…heard good things Thanks Healthy Hombre! Read some of Biology of Belief on a plane ride then never got back to it (story of my life!)

Donna Munro
Donna Munro
1 month 17 hours ago

“The nourishing wisdom that allowed our early ancestors to live a vibrant, disease-free life has been tucked away for convenient, cheap, hyperpalatable food-like products.” that’s a great line. I need help framing the importance of diet for myself. This world makes it very difficult to embrace health on all fronts, and that challenge wears me down. Anything I can do or think toward health gives me strength for more good choices.

Stefan M
Stefan M
1 month 17 hours ago

A notice to take is that as much of a one-note solution liver can seem to be, it’s not a solution to everything ALL the time. Defining a frequency for eating that keeps you out of Hypervitaminosis A is important.

If you’re gorging on liver every single day, either it’s not the nutritious type of liver, or you’re about to have a bad time.

Liver King
1 month 15 hours ago
Agreed… but would you say the same thing about another fat soluble vitamin that most people are deficient in… such as vitamin D? Should we be cautious to not over consume something that we are already deficient in and suffering health consequences from? I think that you have a point here and I think that the answer is maybe… Unfortunately, most people are deficient in vitamin D, A and K. As it relates to vitamin A, our early ancestors would have consumed north of 20,000 IUs of vitamin A per day. They probably would have consumed plenty of sunshine too!!… Read more »
Stefan M
Stefan M
1 month 1 hour ago

LOL. Your post did get approved. Props to the vitamin-movement analogy in the other response.
I wish you would’ve said movement is a fat soluble vitamin. I’d store movement in my body any day of the week!

Anna
Anna
28 days 19 hours ago

Fantastic post! I have learned so much from you in the hour I have been reading this entire *comments* page. Especially the thyroid markers you posted above.

Liver King
1 month 2 hours ago
Would you say the same thing about another vitamin that most people are deficient in… such as movement? Should we be cautious to not over consume something that we are already deficient in and suffering health consequences from? I think that you have a point here and I think that the answer is maybe… Unfortunately, most people are deficient in vitamin D, A and K. As it relates to vitamin A, our early ancestors would have consumed north of 20,000 IUs of vitamin A per day. They probably would have consumed plenty of sunshine too!! Vitamin A and vitamin D… Read more »
Stefan
Stefan
1 month 1 hour ago
Oh, no – I totally agree. 🙂 What I mean is gorging: I love liver of all kinds so much that it has the potential to become “one-note” to me. If I could, I’d replace all meat with it. Which can definitely be a problem. I think the attitude of controlled frequency may not be so important to those used to SAD diets that aren’t fans of offal… But this is always relative based on the person. You may have a point about the combination of vitamin A, D & K. Perhaps even gorging wouldn’t be a problem if you… Read more »
Liver King
30 days 23 hours ago

LOL!! Now I wish the first post did not get approved!! I was so proud of the vitamin-movement analogy. Always find value in chatting with you my friend.

Stefan
Stefan
30 days 21 hours ago

Me too! You know a lot of things & I learnt a lot from reading your comments.
Gotta love your enthusiastic. Keep up!

Wout Mertens
Wout Mertens
1 month 19 hours ago

Oh wow, talk about timely! I have been intermittent fasting for 3 weeks now, only eating a normal-sized evening meal with normal carb amounts, and have definitely been keto during the day. I feel great mentally and I’m shedding some unwantend pounds, but the last few I have noticed that it hurts a bit when I swallow!

I’m guessing my thyroid isn’t super happy about the keto 🙁 I’m now supplementing some iodine will see what happens, I’m liking the mental effects of keto too much to stop now…

Tom Laverty
1 month 18 hours ago

I don’t understand why all the people who push the”keto” diet never give props to Robert C. Atkins and the Atkins diet.
I will understand if it is said that every average Joe believed the fake news media.

Indigo
Indigo
1 month 18 hours ago

So… if keto HAS tanked your thyroid, what’s the solution? I was kinda hoping that would have been addressed in the article. I’m currently doing keto for 2 days, then higher carb/protein every 3rd day (David Jockers recently recommended this).

Mrs. Sweet
Mrs. Sweet
1 month 17 hours ago

Been on thyroid supplementation for 50 years now; body does NOT see the natural stuff, only the synthetic. Keto has been great for me. I’m in the best shape I have ever been. Eat lots of veg, wee bits of fruit, some animal protein and healthy fat. Have to be careful to ‘listen’ to what the body wants: some days I need meat, some not, and I don’t do well on a lot of fat. No grains, dairy, sugars, alcohol, off most nuts after blood work to check antibodies. Definitely NOT starving, though: soups, stews, salads galore.

Kim Mosso
Kim Mosso
1 month 17 hours ago

I will say this, the Keto diet i looked at for my seizures, it was originally a seizure diet, and my docs said no way.

Diva Osorio
Diva Osorio
1 month 14 hours ago
I’ve been on Primal with a low carb and pretty much keto approach for about 7 years. I’m a CrossFit Master athlete and my performance has never suffered as a result of not dumping on tremendous amounts of carbs to support my training. On the opposite, I find that my performance has exponentially improved over time. I do carb refeeds at least once every two weeks, but less than 16 hours after that my ketone readings are already past 0.8. Curiously, I am hypothyroid, which I’ve been for the past 25 years. I take synthroid daily. My thyroid has never… Read more »
Tian
Tian
1 month 13 hours ago
This is a good point. I am 48 year-old female. Perimenapausal. At the beginning of 2017, my HbA1C was 5.3. I also use a glucometer to test my blood sugar after meals. My BS sometimes went to 180 2 hours after meal. So, they were too high. I started a primal type of diet in Jan. 2017. By July 2017, my HbA1C was 4.7%, lowest ever. But my TSH was 19. My TSH was around 2.5 for the past many years. It was never high. I did not lose any weight (BMI is 21). Despite my high TSH, I felt… Read more »
Anne Bourgeois Gary
Anne Bourgeois Gary
1 month 11 hours ago
very interesting, as I’m on ketogenic diet since 5 months not to lose weigh (oh yes Im’ 57 and I just lost 5 kg around my hips for ex) back to my 20 weigh and French 36 size. I feel great so I don’t bother with my thyroid, but if symptoms would occur, I’ll know! Before keto, Ive always been ok with high or low temperatures, and it’s the same now. I live on Réunion island (no grass fed cattle, only big toxic fish, good poultry and organic eggs)and now it’s winter, and the sea is cooler than in summer,… Read more »
Elsie
26 days 3 hours ago
I know how you feel, similar age, size, thyroid issues, cold hands grelottante…, no meds, here in Provence, but long time paleo, now ZC, Carnivore for health. La Réunion may not have grass fed beef, but there are sheep. (lamb and goat for cheese and meat?) I eat lamb and beef and fish. have lived in tropics and don’t worry about the southern fish so much. You have super marchés like Carrefour. I eat their frozen bio hamburgers 100 grams each 110 calories 15% fat. Very good probably mostly grass fed as is usual in France. Ask them to carry… Read more »
Kris Kern
1 month 9 hours ago
Hi Mark. Thanks, that’s great to know about the research. I have read elsewhere that much of the ketogenic diet research that’s been done in humans has been done in young healthy males. Since male and female hormones are different this was proposed to be a reason that women in general don’t tolerate a ketogenic diet so well and caused T3 to become lower. It was suggested that women should have small serves of starchy carbs twice a day. I’ve sort of followed this with my clients who are predominantly women- if they’re re relatively inactive I get them to… Read more »
Change_diet
Change_diet
1 month 7 hours ago

The first research article referenced used processed oil which keto diets explicitly tells to avoid. The research article referenced doesn’t prove anything. Vegetables are allowed in keto but with some exceptions. I am following moderate consumption of total carbs 100 to 130 g especially processed carbs, total fat intake to 80 to 100 g, protein between 50 to 100 g and I feel great.

Tracy
Tracy
1 month 3 hours ago

Great article! I’ve been eating Keto for many years and believe Icelandic seaweed has been a key part of feeling amazing.

Meg
Meg
1 month 2 hours ago

Love this article! I’ve been following higher carb paleo with my Hashimotos, but I’m not losing any body fat, so I’ll give this a go.

Miriam
Miriam
1 month 2 hours ago

All of you seem very knowledgeable about thyroid diets/supplements. Any recommended resources for someone new to the topic? I am hypo but have only been treating with synthroid and I still gain weight and have high cholesterol unless I eat vegetarian and I only lose weight if I eat vegan (or only juice/do smoothies). It is all very frustrating.

Joanna
Joanna
30 days 23 hours ago
I’ve been hypo for about a year, and I find synthoid works great for energy levels, but less so for weight loss. I’ve found that the stubborn gain (which seemed to happen overnight!) won’t budge, but I stop gaining if I stick to low carb but also not very high fat. I’ve tried keto and it makes me feel bloated and I gain weight. But sticking to lean animal protein, greek yogurt but not much other dairy, and lots of vegetables (including tons of avocado to make up for the lack of butter/coconut oil others seem to thrive on) keeps… Read more »
Mark Sanders
Mark Sanders
1 month 39 minutes ago

I’m one of those who had a bad experience from a no carb-high saturated fat diet. Cold hands and feet in the middle of summer, sleeping 10 or more hours every night, hair falling out, and finally my first incidence of angina leading to a stent in a coronary artery. Never again. I eat pretty normally now and have had no problems since. The thing is, not everyone’s body is the same, and there is no one special diet that works for everyone.

Shary
Shary
30 days 22 hours ago
Mark, a no-carb diet would also exclude vegetables, fruit, nuts, and practically everything else. Are you referring to grain and other starchy carbs, or were you eating nothing but protein and fat (a bad idea)? However, you’re right about everyone being different. A true keto diet works well for some medical issues, but IMO is less than desirable as a long-term eating plan. It’s too restrictive in terms of nutrients necessary for proper body functioning. For the same reason, a diet high in saturated fat might not be the best idea. I’m a believer in sticking with a diet high… Read more »
Mark Sanders
Mark Sanders
30 days 11 hours ago

I did eat vegetables – carrots, celery, onions, zucchini, cukes, cooked cruciferous veggies, so it wasn’t like I was only eating meat and fat. So these were low-calorie veggies I was eating. No legumes or grains.

Julie
Julie
30 days 21 hours ago
I recently did a ketosis style eating where I tried to maintain 70 % fat, 20% protein and 10% carbs for about a week. I was not getting enough calories but it was hard to up the calories and refigure all those macro percentages. I did lose weight, not that I was trying to. I was so tired and during that week of ketosis phase, I had a blood test which revealed that my T3 levels tanked! My doctor told me to double my thyroid medicine to get my levels back up! My T3 level was sort of on the… Read more »
Geoff
Geoff
30 days 14 hours ago
I’ve had huge success on a nutritional keto diet. I’ve ditched my heartburn medication after 25 years of absolute sufferring and believe me when I say I tried everything. Im an extremely fit, lean and healthy 47 year old male. My partner suffers from Hashimoto’s thyroid and after 2 months of no medication she feels even better than when she was on the medication. She has had hypothyroidism for 10 years and we are seeing fantastic results across the board. I cannot praise the keto diet enough….just do it the right way. Keep up the cruciferous vegetables, salads and the… Read more »
Anne Bourgeois Gary
Anne Bourgeois Gary
27 days 10 hours ago
yes I’m on keto, I eat one meal a day , breakfast. I live in Réunion Island where half the year we get super avocados, but the cattle eat industrial stuff, fish are big and from hot seas, no omega3, si I take once a day a DHA pill, eat organic eggs and poultry, home made milk kefir (pasteurised milk) and I feel well, I just lost the 5 kg that I prefer not to have, and now keep my weight . I check my acetone expired with ketonix, and curiously at the beginning 5 months ago, the results where… Read more »
Kelli @ Hungry Hobby
26 days 21 hours ago

Very interesting take! It would be really cool to see research comparing keto with high PUFA consumption to Keto with majority MUFA/SFA consumption.

Pompi Borah
26 days 4 hours ago

Great article, Mark, I always felt keto diet is always good for everyone, but today you explained how it can be dangerous too, thanks for sharing such a meaningful, article,
keep sharing.

Zoltan
Zoltan
25 days 21 hours ago

The issue with ketogenic diets is that your T3 levels tend to go south.
I have seen research showing this to be the case when consuming up to 50g net carbs, but I have also seen research demonstrating that this happens at up to 73g/day. Additionally, your reverse T3 levels may go up. The idea that the kind of fat you eat might also be a factor is interesting though.

Marie
Marie
13 days 21 hours ago

Okay, so if I have lots of energy and can go almost all day without getting hungry, I’m a fat burner with a healthy thyroid? Problem is that if I eat more than two paleo meals in a day, I gain weight and then even with fasting, I can’t seem to lose weight.

Have I just taught my body to be efficient on an extremely low calorie level? Can i change this?

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