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The Role of Vitamin D Deficiency in Thyroid Disorders


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This article is part of a special report on Thyroid Disorders. To see the other articles in this series, click here.

Note: This will be my last post until the end of August. My wife and I are going up to the Sierras to hike and soak in the hot springs for a few days before the big acupuncture licensing exam next Tuesday. The day after that we head to southern Mexico to surf and relax on the beach for a couple of weeks.

I won’t have time to respond to comments while I’m away, but please do leave them and I’ll answer when I come back. I’ve got a few more articles in the thyroid series, and next up after that will be type 2 diabetes & metabolic syndrome. Have a great August!

Vitamin D is all the rage. It seems like every day another article is published in medical journals or the mainstream press about the dangers of vitamin D deficiency, and the benefits of supplementation. In this article we’re going to discuss the impacts of vitamin D on thyroid physiology and wade into the increasingly murky topic of vitamin D supplementation – specifically as it relates to thyroid disorders.

Vitamin D deficiency has been associated with numerous autoimmune diseases in the scientific literature. Vitamin D plays an important role in balancing the Th1 (cell-mediated) and Th2 (humoral) arms of the immune system. It does this by influencing T-regulatory (Th3) cells, which govern the expression and differentiation of Th1 and Th2 cells.

Vitamin D deficiency is also specifically associated with autoimmune thyroid disease (AITD), and has been shown to benefit autoimmune-mediated thyroid dysfunction.

Vitamin D has another little-known role. It regulates insulin secretion and sensitivity and balances blood sugar. This recent paper showed that vitamin D deficiency is associated with insulin resistance. And as we saw in a previous article, insulin resistance and dysglyemcia adversely affect thyroid physiology in several ways.

“Okay, big deal,” you say. “I’ll just take vitamin D supplements or get more sun.”

Not so fast. Research over the past two decades has identified a variety of mechanisms that reduce the absorption, production and biologic activity of vitamin D in the body.

  • Since vitamin D is absorbed in the small intestine, a leaky and inflamed GI tract – which is extremely common in people with low thyroid function – reduces the absorption of vitamin D.
  • High cortisol levels (caused by stress or medications like steroids) are associated with lower vitamin D levels. They synthesis of active vitamin D from sunlight depends on cholesterol. Stress hormones are also made from cholesterol. When the body is in an active stress response, most of the cholesterol is used to make cortisol and not enough is left over for vitamin D production.
  • Obesity reduces the biologic activity of vitamin D. Obese people have lower serum levels of vitamin D because it gets taken up by fat cells.
  • Not eating enough fat or not digesting fat properly reduces absorption of vitamin D. Vitamin D is a fat-soluble vitamin, which means it requires fat to be absorbed. People on low-fat diets, and people with conditions that impair fat absorption (like IBS, IBD, gall bladder or liver disease) are more likely to have low levels of vitamin D.
  • A variety of drugs reduce absorption or biologic activity of vitamin D. Unfortunately, these include drugs that are among the most popular and frequently prescribed – including antacids, replacement hormones, corticosteroids, anticoagulants and blood thinners.
  • Aging reduces the conversion of sunlight to vitamin D becomes.
  • Inflammation of any type reduces the utilization of vitamin D.

“Okay, fine,” you say. “I’ll just get my vitamin D measured, and if it’s low, I’ll take supplements.”

If only it were that simple. We now know that certain people with normal serum levels of vitamin D still suffer from deficiency symptoms. How is this possible?

In order for circulating vitamin D to perform its functions, it must first activate the vitamin D receptor (VDR). The problem is that many people with autoimmune disease have a genetic polymorphism that affects the expression and activation of the VDR and thus reduces the biologic activity of vitamin D. Studies have shown that a significant number of patients with autoimmune Hashimoto’s disease have VDR polymorphisms.

In plain English, here’s what this means: if you have low thyroid function, you might be experiencing vitamin D deficiency even if your blood levels of vitamin D are normal. It also means that, if you have a VDR polymorphism, it’s likely you’ll need to have higher than normal blood levels of vitamin D to avoid the effects of vitamin D deficiency.

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“Okay, I get it,” you say. “I may need higher vitamin D levels than the average person if I have one of those genetic defects. So tell me what my levels should be!”

Well, this is where we venture into murky territory. The question of how high vitamin D levels should be is very difficult to answer in the case of someone with autoimmune thyroid disease. Studies suggest the optimal 25(OH)D level is 35 ng/mL for the average person. Some researchers (notably Dr. John Cannell and colleagues at the Vitamin D Council) have suggested that 50 ng/mL should be the minimum level.

The bulk of the evidence, however, doesn’t support that claim. For starters, the other authors of the study Dr. Cannell used as the basis for his 50 ng/mL recommendation came to a very different conclusion from the same data. In the paper they published in the American Journal of Clinical Nutrition, they wrote that their data confirmed the previously acknowledged optimal level of 35 ng/mL – not the 50 ng/mL suggested by Dr. Cannell.

What’s more, some recent studies have shown that higher isn’t better when it comes to vitamin D. A study in the American Journal of Medicine found that, in most people, maximum bone density occurs at 25(OH)D levels between 32-40 ng/mL. When levels are pushed above 45 ng/mL, as recommended by Dr. Cannell, bone density starts to decrease. Another study published in the European Journal of Epidemiology found that South Indians 25(OH)D levels above 89 ng/mL were three times more likely to have suffered from heart disease than those with lower levels.

If you’ve been following this blog for a while, you know that we don’t put too much faith in epidemiological studies. They don’t prove causation. They only show a relationship between two variables. But the relationship of vitamin D to calcium levels also provides a plausible mechanism by which high 25(OH)D levels could increase the risk of heart disease.

Complicating the matter further, recent work by researcher Chris Masterjohn suggests that the harmful effects of vitamin D toxicity are at least in part caused by a corresponding deficiency in vitamins A & K2. The fat-soluble vitamins A, D & K2 work synergistically, as Masterjohn has described in his Cod Liver Oil Debate article and a recently published scientific paper.

Masterjohn’s hypothesis, which has been confirmed by others, raises the possibility that the higher levels of 25(OH)D that were linked with lower bone density and heart disease may be safe if vitamin A & K2 levels are sufficient. Unfortunately, there is no clinical evidence (that I’m aware of) that helps us to answer this question.

“Okay, okay,” you say. “Just tell me how much to take already!”

I wish it were easier to answer this question. Really, I do. I think about it a lot for my own patients.

The research is clear that 35 ng/mL is the minimum level for optimum function for healthy people. But people with autoimmune thyroid conditions aren’t healthy.

They often have GI disorders, inflammation, stress, excess weight, VDR polymorphisms and other factors that impair their production, absorption and utilization of vitamin D. This suggests that the minimum 25(OH)D level for those with AITD may be significantly higher than for healthy people.

My current approach with these patients is to do a cautious trial of raising their serum levels to a range of 60-70 ng/mL. If their symptoms improve at this level, I will then switch them to a maintenance dose while watching for clinical signs of vitamin D toxicity. These include kidney stones (also a sign of vitamin K2 deficiency), low appetite, nausea, vomiting, thirst, excessive urination, weakness and nervousness. I will also monitor serum calcium levels, because elevated calcium in the blood is a sign of vitamin D toxicity and a significant risk factor for cardiovascular disease (especially in the presence of vitamin K2 deficiency). Calcium levels above 11-12 mg/dL (or 2.8-3 mmol/L) are indicative of vitamin D toxicity.

I will also make sure these patients are getting adequate amounts of vitamin K2 and vitamin A in their diets. Sources of vitamin A include organ meats, cod liver oil and full-fat milk and cream from grass-fed cows. Sources of vitamin K2 include fermented foods like natto, hard cheeses and kefir as well as egg yolks and butter from grass-fed cows. I may also use a vitamin K2 supplement (MK-4/MK-7 combo) if patients can’t tolerate fermented foods.

Finally, if you’re interested in finding out if you have a VDR polymorphism that could be affecting your metabolism of vitamin D, Genova Diagnostics has an Osteogenomics panel that tests for them. I’m not sure how much value this test has clinically, however, since it doesn’t provide any information about how the VDR polymorphism affects vitamin D metabolism in each specific case. That’s still something that would have to be figured out using the “trial and error” process I described above.

In time we can hope that the explosion of research being conducted on vitamin D will lead to more clarity on the question of appropriate serum 25(OH)D levels for people with autoimmune diseases. For now, we have to make our best guess based on clinical results and anecdotal reports.

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  1. I have hypothyroidism and have the usual symptoms of estrogen dominance many women in perimenopause have which includes having hard time losing fat in hips and thighs. I discovered somethings that will get the fat off and also make you less moody. First is progesterone cream because most woman over 35 are low in progesterone and way too high in estrogen. Then you can also take Calcium D-Glucurate and DIM (Diindolylmethane) both of which are made from certain vegetables and they help both men and woman who are estrogen dominant to loose fat around lower body and in men will lose the manboobs. It helps by lowering estrogen levels and also helping the liver to process out excess hormones floating around in the body. It takes 2 months of taking both daily before the process starts to kick in but it really does work! I have been working out 2 hours a day every day nearly for over 4 years and nothing was making the butt, hip, thigh fat budge untill this. It’s finally starting to go away. I keep measurements of each part in order to gauge it’s effectiveness. Research these supplements for yourself. Hope that helps others.

  2. I have Hypothyroidism going on 19 years now and was just diagnosed 2 years ago with Hoshimotos. They tested my Vitamin D levels and found that I was low and told me to start taking 2000 IU’s a day, I did that for a year and when I retested I was still too low. I was told to start taking 5000 IU’s a day and retested 90 days later and I am still too low now they want me to start taking 10,000 IU’s a day. The PA that has me taking the supplements didn’t say to retest after a certain amount of time, do you think it would be a good idea to recheck levels again soon? Also after being on 50mcg of Levothyroxine for 18 years last February my TSH levels were extremly high and was put on 100mcg and then retested 30 days later and levels were still too high and then was put on 150mcg of Levothyroxine. I was retested 90 days later after being on the 150mcg my levels were way to low, now I’m on 125mcg and levels are fine. What do you think could make my levels go so crazy after being on the same dose for so many years?

    • Yes, you should retest while on 10,000 a day. You shouldn’t stay on that long term unless you need to. This happened to me too, not getting my D levels up even with 10,000. The thing that finally made it go up was adding K2 to the mix. That finally after probably two years of trying made my levels rise. D shouldn’t really be supplemented without the K2.

      Good luck.

      • Thanks MPW for the information! I think I’m going to go back and see and Edocrinologist and have them help me out with this. I’m not confident that my PA is real familiar with the Vitamin D problems of a person that has Hoshimotos. I not only have Hoshimotos but I also am over weight and am almost 50 years old, I have alot of things going against me right now.

    • I was diagnosed with Hashimoto’s 9 years ago and I can definitely relate to your post. My thyroid bounces around from high to low at an alarmingly fast rate. One endocrinologist has suggested even taking my thyroid out to keep my levels from dramatically changing all the time. The longest I have ever gone with “almost normal” numbers was 6 months and even then I was slightly low. It seems like when my Synthroid gets increased due to being hypo, my body overreacts and then I get majorly hyper. I have had many cardiac issues due to the constant ups and downs. I have been told that eventually the Hashimoto’s will kill my thyroid and I will just stay low, but mine continues to bounce around even though my thyroid antibodies are some of the highest they have ever seen . I have gone from very low to dangerously high in a matter of 2 weeks. I have learned that flip flopping thyroid numbers is just a part of this crazy disease. That being said, I was also recently diagnosed with very low Vit D. My level was somewhere between 8 and 9. I have been feeling the worst I have ever felt. The fatigue and muscle/bone aches sometimes keep me in bed for days. I have just started supplementation and desperately hoping it will help. I was told that auto-immune diseases can interfere with absorption of many things. I also tend to be low on ferritin, B12, and potassium as well. I hope your thyroid calms down. I did have to switch from levothyroxine to synthroid because my body didn’t seem to respond to levothyroxine. Synthroid seems to work better. I have heard this from many thyroid sufferers as well. It might be something to think about. Best wishes to you. I know how hard it can be to deal with a crazy thyroid.

  3. I have hypothyroidism (5years). I have been taking Levothyroxine my dose has been at 112mg for about a year now. In October I started getting stiffness in the hands and feet while asleep but as soon as I wake up its gone. I recently tested positive for thyroid antibodies doctor said they are supposed to be under 10 but mine were 3,016. Now I’m starting to freak out. Does anyone have any recommendations or advise?

    • My antibodies were >1000 and my endo said they would probally stay that way till my body killed off my thyroid. 🙁 I don’t like this Hashis thing.

  4. Hi,

    I am wondering if this thread is still active- but the original post by Dr. Kresser seems to be making a balanced scientific argument. I am 35 yo, 5ft 9′, 150lbs +/-5lbs (over the past 10 yrs) and a non-vegetarian.

    here is a step by step of what has happened:

    About 10 yrs ago- I first started noticing stomach issues- malabsorption- / steatorrhea ( no IBS diagnosis) – no treatment.
    2. then came low B12- concurrent with that- was numbness/tingling in hands and legs– treatment: B12 shots 1g/ every month then tapered off- some OTC supplements..and then over the years- blood levels have always been hovering around the ‘acceptable range’
    3. then came fatigue- loss of focus, tiredness in the legs, malaise- foggy brain..5 yrs ago
    a sleep study 3yrs ago revealed sleep disorder and restless legs..
    a neuro analysis indicated weirdly enough moderate to severe ADHD-
    4. a concurrent blood test for the first time (maybe checked for the first time) high LDL – no issues with thyroid.
    5. present: high LDL (4.6mmol/l), low Vitamin D (59nmol/l)..and all the GI symptoms continue-

    So- should I take Vitamin D supplements? or should I try and figure out whats wrong with my GI absorption- i.e. this is what has been wrong for the longest time..

    would really appreciate any input..

    thank you!

  5. Hi, I just wanted to let everyone know about this website https://www.directlabs.com
    Ordered my own vitamin D test for $60 and had results in 2 days.. My question is this, I have all of these symptoms of vitamin D deficiency, but my level showed up at 35. That is with taking 2500 Iu a day. I was really hoping that was going to be my answer, is it possible for me to have symptoms with that level? Symptoms are muscle pain, trigger points, back pain, hip and buttock pain, no memory, joint pain, tired, foggy brain, sleep issues, I cannot exercise. I am pretty tired of feeling this way, it has been about 5 years Now and would love to figure it out . Thank-you

    • Hi, I have autoimmune Hashi and low platelets. After years of dealing with brain fog I descovered it was from allergies. I started taking a claritin or zyrtec everyday and I have been free from the brain fog. It is wonderful !

    • I started feeling bad about 9 months ago. Tingling in my feet, hands, fatigue, weakness, muscless in my legs and arms aching, my heart fluttering, shakiness. Awful. I finally had blood tests that showed my D level to be 25. I have been taking different amounts of D3 for two months now. I’m a little better but not much. It’s awful stuff and sometimes my muscles ache so bad I can’t stand it. I need to be tested soon but I just lost my job so maybe I will order a do it yourself test. I have been surfing the web and so many people who have low D levels feel SO bad and it seems to take a long time to raise the levels. Trying to figure it out. The amount of D people are taking is all over the board so I’m trying to figure it out. I take minimum 5000 mg every day and sometimes I take 50,000. This is frustrating and hope that it’s over soon. What a nightmare.

  6. Hello everyone.

    Can someone point me to testing for the VDR Polymorphism? The test that Chris recommends from Genova Diagnostics (Osteogenomics panel), is pretty involved. Isn’t it possible to just test for the VDR polymorphism? I have Hashi’s and am not tolerating Vit D supplementation at all. I’ve been taking it for a long time and only just now figured out some of my symptoms are Vit D supplementation. Not sure what I’m going to do about keeping Vit D levels up.


  7. I wanna know about toxicity of high vit d level with high TSH
    n relatively low T3

    • Hi Rubi,

      If you take the doctor subscribed D3 for a short while, like a few weeks, it is fine. However, once you reach a certain point, and continue taking high doses, you run the risk of poisoning yourself. When you make D from the sun, your body knows when to stop.

      Make sure your doctore checks it while you are on the prescription after about two weeks.

  8. Hi There:
    I’ve been diagnosed with Hashimoto’s recently and my thyroid levels aren’t too far off of being “normal”. I’ve had increase in weight and have battled depression and fatigue, fog brain, for years. I take levothyroxine and take 10k iu of Vit d3/day. My question is, some of my symptoms have gotten better, but I would like to see continued relief. (weight loss and depression relief) What kind of Dr do I see to help me? I’ve just seen an endocrinologist. He’s increased my levoxy dosage and didn’t mention anything about supplementation. Should I see a holistic Dr in combination? I take a new blood test in 6 weeks.

    • Hi Melanie,

      10,000 units of D3 a day is A LOT. I would cut it back to 4000 at the most. Drink milk with it.
      You could see a holistic doctor, but Most people go to hematologists.
      Definitely take 5000mcg sublingual methylcobalamin (B12) each day, B2, Folic Acid, C, and Magnesium.

  9. Hi Chris,

    I’m glad to find some articles like this, discussing the Vit. D/autoimmune connection, and the cautions required. I have had psoriasis since I was very young, and now exploring whether I have hypothyroidism as well. Are you familiar with the Marshall Protocol? It is a protocol that treats autoimmune diseases, based on the premise that (in very laments terms) VDR’s can be blocked by specific mutating bacteria. If you’re familiar with it, I’m curious what your thoughts are on the Marshall Protocol for treating autoimmune diseases.

  10. Hey Chris. I appreciate your cautious approach to Vitamin D deficiency and it’s related issues… I’ve been seeking information on Vitamin D deficiency and possible related conditions since December. I live in Guadalajara, Mexico and have found that there is absolutely no understanding, concern or solutions for vitamin D deficiency here. For this reason, I find myself researching on the internet and awaiting a shipment of Vitamin D3 from the U.S.

    My issue is a bit more complex than the possible modern 20th-21st century “American” lifestyle caused vitamin D deficiency. I’m a 43-year-old male carrier of Familial Anenamatous Poliposis/Gardners Syndrome. I had my colon removed in 1983 and my rectum removed and reconstructed with my Ileum as a J-Pouch. 7 years ago I was diagnosed with hypertension, gastritis, duodenitis, inflamed gallbladder due to many gall stones, ulcers in the entrance of my stomach (possibly caused by H. Pilori), and hiatal hernia. I elected against removal of my gallbladder (due to economic limitations) and stopped seeing the internist and other doctors and stopped taking medications after being given an impossible diet that excludes almost all foods with the exception of Salmon… I researched the internet for alternative diets and it seems that I lowered my bloodpressure and my cholesterol levels and removed the inflamation of my gallbladder.

    With all of my diet changes (not lowfat, but much more vitamin/mineral–fruit/vegetable conscientious) and periods of exercise, I found that my weight didn’t decrease and my energy levels didn’t increase… Fine. For years I dreamed of having the flexibility for being able to exercise regularly and for living in a city with ready access to descent parks for running and hiking. 1.5 years ago we located permanently to Guadalajara and found ourselves (my wife and I) with great parks for both heavy-duty hiking and for running. From March through July we were ravine hiking (1000 xs better than a Step machine) for two hours 5 days per week. If you want to feel your heart popping out of your chest… I lost weight. Possibly 10 pounds during that period. I believe I gained a ton of leg, gluteal, stomach and back muscle from the ravine climbing making it incredibly easy to change to running 40 minutes 4 xs per week in August. I’ve run on and off over the past 20 years and this time around (much more enthusiastic and probably much more responsible/conscientious) I noticed something very discouraging… From September until late November, I noticed that my body had decreasing energy for the runs, decreasing to between 28 and 33 minutes 4-5 days per week… 4 kms (2.6 miles). This would be fine for me if the situation didn’t continue evolving negatively. Late in November I began experience muscle pain (lactic acid burning) in my right calf at the halfway point… And then I began experiencing the burning in my thigh. And then pain in my left knee… all the time the burning beginning increasingly earlier in the run, until I couldn’t make it past 8 minutes…

    Just before experiencing the burning, I had been experiencing what I thought was recurrence of the inflamed gallbladder on the right side of my gallbladder just below my right rib cage and a pain behind my left back ribs where I imagine is my left kidney or my stomach… I figured that the pain was from the ulcers and we made an appointment with a GI.

    During the interview/exam with the GI who supposedly is amongst the elite of Mexico (was the director of the Mexican GastroEnterological Association) and supposedly met my J-Pouch surgeon during a conference in Chicago. He asked me if my surgeon was Dr. Gorstein when I said that my surgeon supposedly was #1 in his field in the world…

    The GI here in Guadalajara didn’t want to do an Upper Endoscopy since he said it was enough that I had one 7 years ago… not even to check the ulcers or my duodenum… He didn’t believe I had problems with my gallbladder and that the pains weren’t caused by the ulcers or possible kidney problems… Nor did he ask for a sonogram… However, he said that I had hypertension he believed could cause kidney disease he called hypertension of the kidney (although that doesn’t exist)… and he recommended a visit with a cardiologist… The GI mentioned that the J-Pouch is constructed with the Ileum guarranteeing vitamin B-12 deficiency and other malabsorption problems. Instead of requesting blood tests, he suggested I inject B-12… He also prescribed an anti-cramping medication for the large intestine.

    The B-12 injection coincides with the extreme muscle fatigue. But doesn’t make sense. The following day I began with the more extreme running problems and also met with the Cardiologist who said that I must take blood pressure medication for the rest of my life. He also prescribed pain relievers for what I am certain isn’t back muscle pain. I purchased the medication. However, I didn’t use it due to it’s ban in the U.S. by the FDA due to risk of causing heart attacks… Yes, you read correctly; the cardiologist prescribed a medication banned in the U.S. due risk of causing heart attacks. The BP medication he prescribed is also a diaretic… I imagine I don’t need a diaretic due to not having a large intestine nor a rectum, mainting me constantly on the edge of dehydration. The BP medication also creates a risk of causing liver and kidney problems. However, he didn’t ask for liver or kidney tests before prescribing the BP medication; he prescribed those tests for day 28 of taking the BP meds.

    Since the GI mentioned J-Pouches and malabsorption problems, I decided to research deficiency problems connected with muscle cramping or muscle burning and stumbled upon Potassium, Vitamin B-5 (if I am correct) and Vitamin K (if I am correct). I read that B-12 injections can cause potassium deficiencies, possibly leading to muscle pain. I also read that potassium deficiencies can lead to hypertension and heart attacks. So, I ordered blood tests for all vitamin Bs, Potassium, Iron (since I was almost low in Iron when diagnosed with duodenitis 7 years ago) and an Ultrasound… For some reason they threw in a Vitamin D test also…

    The ultrasound revealed that most of my gallstones had disappeared (3 small ones remain) and that my gallbladder wasn’t enflamed. The ultrasound revealed that my pancreas, kindneys and spleen were normal…

    The blood tests revealed my B-12 levels over the roof (although I didn’t have high energy levels). It also revealed normal iron and Potassium levels. The laboratory/clinic didn’t understand testing for Vitamin Bs that weren’t B-12… Go figure! My vitamin D came back low 18.5 (here considered almost normal, although must of the modern literature states that 18.5 really is lower than just an insufficiency)… A few weeks later I took the blood and urine tests prescribed by the Cardiologist, revealing that my Cholesterol, Glucose and sodium levels were towards the low range of normal… However, my triglicerides were at the low range of high… The cardiologist mentioned that the triglicerides were probably raised by the diaretic aspect of the medications, prescribing the same medication but without the diuretic part… I haven’t filled that prescription, opting for walking in shorts without a shirt for 40 minutes every other day and waiting the vitamin D3 10,000iu shipment from the U.S.

    The cardiologist didn’t want to talk about the possible connection between Vitamin D and high blood pressure… It’s not from low potassium levels. Nor is it due to high cholesterol levels or high sodium levels… Seems obvious. However, here in Mexico, you can’t readily find Vitamin D3 suppliments above 400UIs and it costs 1600% more than in the U.S. However, for some reason or another he suggested that I have my thyroids tested later on… (The GI checked my thyroids and said they were small). Aside from not losing much weight through regular exercise, the only possible symptom of hypothyroidism I notice is that over the past 5 years or so, the outer half of my eyebrows have all but disappeared…

    I hope you have the time for reading this and responding…


    • Ross, Did you ever resolve your issues with the burning of your muscles? And your disappearing eyebrows?! I know that when my eyebrows have disappeared (twice) it’s been due to my off-kilter TSH levels. My thyroid was removed some yrs back due to nodules that kept filling up with fluid. I finally asked that it be removed and on biopsy it was found to have pre-cancerous cells. Since then, recently, I have been found to have low lvls of Vit D (24ng/dl) so I’ve been put on 50kIU/wk for 90 days along w/ my usual supplement of D3 w/ my calcilum carbonate 2x/day pills I take as part of my regimen. I have Lupus, you see, and have had it for over 27 yrs now. It’s been treated and am now in “remission” but I have fibromyalgia so the pain and stiffness of my joints is pretty bad. If not the fire, then it’s the pan for me.

      I’m hoping you’re still in Guadalajara and able to enjoy it’s ravines! I was on a road trip on a motorcycle through there in 2002 and had it not been otherwise, I’d’ve loved to have settled there. Still would if I had my druthers.

      Please post an update if you can, to my e-mail if you can’t. I’m REALLY interested in the outcome of your case!!!

  11. Hi how low is to low, My test show level was at 16, started researching about it, all the symptoms they say I have also have had thyroid issues one side was removed and there was a small amount of cancer, still have 1/2 thyroid and they don’t know if that side has cancer, kidney issues have had sugar issues for years, skin problems I could go on so I look at all lab work I have and see as far as I can tell have been low for at least 8yrs, But none of my Dr ‘s seem to concerned, so I wasn’t but now don’t know.is 16 just a little low…

  12. Something I recently discovered is if you take Vitamin A supplements it can interfere with your Vitamin D3 absorption. So take them different times of day so there is no interference. I think this is the reason my blood test barely had me in normal range despite many hours of sunlight per week during warm weather plus also taking 10,000 IU of Vit D3 per day. Taking Vit A in evening and going to retest in a few months and see if my level changes.

    • Hey Angela, I don’t believe supplimentation would interfer with production of Vitamin D in the skin… However, the research claims that if you are sufficiently overweight to classify as obese, the vitamin D produced in your skin will be trapped in your fat cells… That said, you may be a skinny Minnie… and this wouldn’t mean diddly 🙂 I’m interested in knowing if you levels increased ingesting the 10,000 IU per day and how long were you taking it. And did your doctors or the instructions on the bottle suggest you take the suppliments during or right after eating some form of fat (could be avocado, yogurt, olive oil; doesn’t have to be unhealthy)? … because… if Vitamin will not be absorbed without some form of fat attachment. Vitamin C and the Vitamin Bs are water soluble. Vitamins A, D, E, and K are fat solable. The fat soluble vitamins stay in the body longer. The water soluble vitamins leave your body in the urine. So, if you have diarhea… or you dring a lot of coffee or black tea… or if you are taking a diuretic for high blood pressure or for inflammation… or bloating… you would have to up your intake of the water soluble vitamins. But, if you are on an anti-fat diet, you are probably slowly killing yourself 🙂 Chris isn’t following these conversations…

      • Hi Ross, At my recent doctor visit he would not retest my Vit D. Apparently my insurance doesn’t allow frequent testing. Will try again in a few months. I’ve been taking 10,000 IU of Vit D for over 2 years. Prior to that I was on 2,000 & 4,000 IU. All totaled this is about 4 years straight I have been on Vit D and have not gotten any colds or sinus infections, my health has improved dramatically despite having an autoimmune illness called CREST. This winter I decided to start indoor tanning and am curious again whether my D levels would get too high. But considering I was spending hours outdoors last summer while taking 10,000 IU and barely just testing into low-mid of the normal range on D I am still probably not overdosing. I don’t have symptoms of too high D. I also take E & K and switched from A to Beta Carotine.

        I am concerned now over the recent comments concerning B12 injections as my doctor prescribed biweekly and now weekly home injections of Vit B12. He said it would help with my weight loss plus also chronic fatigue and he figured would help as I was treated for Lyme disease a few years ago by another doctor when I lived elsewhere. From what I have read Lyme spirochetes devour B12 stores as an energy source leaving the person chronically low. As far as B12 helping weight loss I personally didn’t believe my doctor. But after I have an injection I lose 2 lbs over a matter of a couple days hence he changed me from biweekly to weekly doses. I am concerned over the B12 and potassium comment, but do not understand what the mechanism is that would cause injected B12 to lower potassium. I already have low potassium, explained by one former doctor being related to being a salt loser because of an adrenal condition. It seems to be something runs in family as my grandmother has had low potassium problems throughout her life too. I take 600 mg potassium pills per day in order to avoid severe leg cramps and muscle spasms. Otherwise I wake up in excruciating pain from morning leg cramps and in summer when I am so active sweating like a horse I have to be extremely careful. I also take magnesium glyconate before bed. I have the muscle cramp problem for years now and have only started B12 just recently so it isn’t the cause of the problem, but at same time don’t want to make it worse if indeed injectible B12 is bad. I did not find the sublingual B12 to work at all.

  13. Thank you for this article! It’s the first time I’ve come across a connection between Vitamin D and blood sugar issues. I’ve been feeling terrible (vertigo, hypoglycemia- after eating, exhaustion, flushing, freezing, foggy, eczema) and was recently diagnosed with a multinodular goiter on my thyroid but my tests came out great – except for lower than normal Vitamin D despite supplementing with 1000 iu. My doctor is baffled so I’m trying to piece things together. Now, I’ll look deeper into this connection between Vitamin D malabsorption and insulin. Any further guidance or literature recommendations would be greatly appreciated.
    Thank you!

    • Hi Eva,

      Your doctor is baffled probably because he doesn’t realize that 1000iu per day is insufficient to increase one’s levels. There’s a study on PubMed that showed that HEALTHY men needed 3,000-5,000 ius a day just to maintain their levels. You could be malabsorbing it, but it could also be that you’re not taking nearly enough in the first place.


  14. I see a pattern of foods that have vit D also contain iodine. I further see a pattern of obesity and thyroid issues (and multiple cancers) up ticking when the baking industry switched from using iodine in baked goods and introduced bromines, a known goiteroid and carcinogen; and ‘anti-iodine’. I strongly suspect that iodine needs to be added to the D balancing equation, and that foods containing bromine, and soy be completely avoided.

  15. Chris,
    Eureka! I found you! Diagnosed with Hashimoto’s and severe Vitamin D deficiency in June: TSH 18, TPOAb >6500, Vitamin D level was too low to detect.
    Have been taking Synthroid and 50,000IU D4 1x/wk but still struggling to get well after 5 mos of ttmnt. TSH levels bouncing around; Vit D has only climbed to 15 (dose doubled to 50,000 IU 2x/wk), cholesterol going up not down! (Dr. gave me until Feb to lower it – high 200s w Triglycerides above 190 – then statins) Ugh. Very motivated to get well!
    I’m not taking anything other than Synthroid, prescription Vit D and started 200mg Selenium this week. I purchased your High Cholesterol Action Plan. I know I’m FUBAR. Any other recommendations? I am extremely interested in a consult.

    • Suz,

      Have you considered magnesium deficiency? You should research it in regards to converting to active form of D and cholesterol levels.

  16. Hi Lisa,

    I know this is a lot easier said than done, but try to be as patient as possible — I think once you get your vitamin D levels up, and also your b12, that a lot of those other tests and/or diagnoses won’t be necessary. All of your problems MAY be due to your incredibly low “D” levels. (Because they’re so low, you may need more calcium, magnesium, K2 and boron too, but Chris would know more about that.)

    People with multiple sclerosis have completely healed after restoring their vitamin d (and sometimes b12) levels, so there is hope.

  17. I have been feeling bad for years. I would constantly say to family “my hormones are messed up”. I could feel it. Weight gain started, recurrent kidney stones resulting in multiple lithotripsy procedures. Then irregular periods, mood swings, etc…. they would check thyroid…levels were always normal. I also habe had IBS for some time. Ended up with gall stones and removal of gallbladder. Ended up with hysterectomy. Was seeing GYN for years with all my symptoms…I could tell he was frustrated with me. He just wanted to give me hormones and anti depressants. I refused antidepressants assuring him I was NOT depressed….something was wrong. I decided to go to an endocrinologist after years with GYN. On first exam she tells me my thyroid is enlarged. Again..labs reveal normal thyroid levels except she ran an extra test I never had done before…anti TPO. It was elevated…. sonogram of thyroid revealed multiple nodules and chronic thyroid disease. I have been on thyroid hormones now over a year. Lab levels always normal but I continue to feel worse and worse. Finally, they order vitamin D. My level was 8.5. She said she had never seen one that low before. B12 is also low. Now they are running a pituitary panel…im waiting on results. I went in to early menopause prior to hashimoto diagnosis. I continue with IBS….and they are saying I may need growth hormone. I will soon have a Stim. Test. I feel hopeless…I just want to feel better.

  18. Yes, they compete to some degree but that doesn’t mean they cancel each other out. A & D appear together in fish and organ meats which have been highly prized foods in traditional hunter-gatherer peoples for millennia. When there’s any apparent conflict in the scientific data, I always look to anthropological evidence and the natural composition of foods to resolve it.