Thyroid UK
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Vitamin D lowers TSH level?

Since I've supplemented with Vitamin D my TSH level has come down from 5.12 to 1.6.

I posted incase others have found this too or maybe it is just me. (PT, not on Levo or other medication, just the occasional multivit, brazil nut & magnesium spray). Although I feel much better painwise than this time last year, I'm still cold, tired and brainfoggy etc. Jane :D

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I had know idea this could happen! I have been prescribed 10,000 iu of D3 per day together with an increase in Levothyroxine. I really think they should be re checking my bloods before 3 months.

I hope you start to feel better soon x


Thank you, I don't know really, it just what happened to me. On the downside it means my Thyroid symptoms remain untreated. (despite 5 high TSH results over 2 years but was discharged from ENT doc on one low one)

I imagine that high dose should work pretty quickly! J x


I do sympathise, I started to have high TSH results in 2007 but my GP failed to mention it and I carried on for 2 years before a rhuematologist diagnosed Hashimotos after testing for antibodies! It sucks that you remain untreated especially as you are so knowledgeable about the condition, I am sure you would give any GP a run for their money!

Take care

Ali x


I have noticed this myself as well.


Have certainly noticed that it has brought mine and my son's blood pressure down, so if it brings your TSH down does this mean your T4 and T3 could possibly rise? Aches and pains have certainly lessened. Janet.


I was wondering if it was because Vit D helped the actual Thyroid hormones (T4 & T3). Blood pressure too? I'm glad it helped you both.

I have noticed that folks have reported needing less Levo in Summer (and increase in Winter). J


This is interesting as my husband now takes Vit D3 as he was low although not deficient like myself. However his TSH has fallen from 2.5 to 1.6 since doing so but his T4 has also fallen from 10.5 to 9.3 (9-23) which has totally confused his GP. I wonder now if this is the anomaly we were looking for.


goodness knows Ive almost given up.


Just to be awkward my experience has been the opposite!

I'm currently on no thyroid meds but have been furiously supplementing D, B12, etc, and noticed from my last blood tests that my TSH had risen slightly and T4 dropped slightly - though not significantly given that I'm on no meds.


Hi spare ribs, I've read that adequate vit do is needed for thyroxine conversion in body, I def notice the diff for taking it. I'm strong advocate for it now and always nag others to get there's checked. If only all the docs would follow suit.


I have been supplementing 4000iu per day having only started Levo 8 weeks ago. I had a blood test last week and get the results, including vit D levels on Wednesday so will see what it is and post back. I am one of these very fair people who have used sunblock for years and have tried to stay out of the sun as I burn very quickly.


Interesting - yes it has happened to me but I never made a connection.

I have had my thyroid monitored over the last 3 years. I started with a TSH of 5.1 and testing positive for thyroid antibodies but have never been medicated for thyroid..Over the last 18 months I have been medicated for deficiencies in B12, folate and Iron and since November receive B12 jabs every 3 months . Thyroid Antibodies have been rising over the 3 years and were around 800-1000 until my test in November when they had halved to around 400. I suspect that this was somehow down to cutting back drastically on eating wheat as I do seem to have issues with that.

TSH has mostly been around 4.0 for the last 3 years.

I was prescribed Vitamin D back in November at the same time as I started B12 jabs. (A week of 40000 iu followed by 10000iu daily) .I had a thyroid test in April and TSH was down to 1.8. - lowest I have ever returned. I now take a slightly lower daily dose of Vitamin D. Its Obviously hard to know if the change is down to Vit D, the B12, the wheat or just the madness of the thyroid. I shall keep up my D3 in case!


Another illustration of why TSH is a useless measure in the diagnosis and treatment of Hypothyroidism :-(

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I was on t3 /t4 therapy. Whilst on this I found my Vit D was low at 25 nmol/L and I felt awful. First time I had found this. After supplementing 3000 iu a day to get it back in to 80 nmol /L mark . I then maintained it at this level with 1000 iu a day for 4 years.

I then went to T4 only therapy, within 2 months my vit D level crashed back to 19 nmol/L. I then supplemented 3000 iu a day to get it back to the 80 nmol /L mark for a month. Then thought let me try and get it higher and carry on up into the 100s. So I carried on taking 3000in a day for another month then tested and then another month then tested and found I had stabilised at 70 to 80 nmol/L and did not go any higher.

So for me T4 only therapy uses more vitamin D to get to the same Vitamin D level of 80 nmol/L. I needed 3 times the amount to stay there. Also this is where I noticed the TSH going lower as well. I also have noticed in previous blood tests that when my Vitamin D levels were higher my conversion to FT3 was higher as well.



Re Vit D -my specialist said it would be helping with the uptake of thyroid hormones in the system. I can't give you any links to prove this as it was a verbal comment. Vit D certainly helped me. I had blamed all my aches and pains on hypothyroidism but it turned out to be vit D deficiency....not the hypothyroidism causing these symptoms. i was already well medicated on a natural dessicated thyroid med -Erfa -at the time.

I have since supplemented B12, folate and B complex as well as the vit D, largely cut out grains and have had a further improvement still. I have also had to reduce my dose of thyroid meds as I am absorbing them much better now - so needed to drop my dose by 1 1/2 grains!!

Certainly worh everyone checking these minerals and vitmains out carefully as they are usually easily remedied.

Initally I was not convinced over the grain free approach -but I have to admit it makes a big difference to me as I have more energy when I don't eat grains. I can really tell when I have eaten grains so best to avoid! The GP has already checked me for gluten intolerance but this is not a problem for me according to their blood tests at I find it very interesting that a grain free diet helps my energy levels so much. I don't eat grain alternatives that they show on the 'free from' shelves. I do eat potatos and plenty of veg!


I found that IBS was reduced a lot by replacing commercial wheat [hybridised] by Spelt. It can be bought from specialised bakers [not cheap] but Asda sell it local to me at £1 a small loaf. It is a lot better digested, too.

I'm not gluten intolerant but empathise with your experience with ordinary wheat.

Spelt is definitely easier to live with if you miss that occasional treat- I find I soon pay if I eat white 'bread',.though.

It's been said that most immune reactions in Hypo [antibodies]cases is driven by the gut being out of sorts- it is the source of our immune system.

A connected was posted elsewhere that when the wheat protein enters the bloodstream [in allergy cases/leaky gut] the shape of the molecule is very similar to thyroid hormone- and is even butterfly shaped.

Very poetic, given the shape of the thyroid gland,- but interesting to contemplate.


Thankx Tegz -tried the spelt but I am just better of without it all to be honest.... i can get awaywith the odd bit but what happens is I feel sluggish and tired and I put loads of weight on round my middle. So have decided it just isn't worth it.


Maybe I should avoid even spelt if I can't find a hormone imbalance...also try to boost Vit D more, as you do. I'm not on any thyroid meds.

The new seeded wheatfree bread seems better than earlier stuff I tried.

My folate is over the limit [>20] so B12 takeup is suspect -but the Doc hadn't heard of that one!

I do supplement Magnesium and Zinc most days [Mg at lower limit]


Well tegz without being rude about doctors one is left to wonder what docs have 'heard of' I think many doctors these days are no longer trained in the art of analytical doctoring -they just look at the list and if it doesn't fit their protocol on their computers it doesn't exist! Of course if they took time to stop they would realise that medicine has principally developed by two routes :-

1. the big pharma companies that want to sell their products - doctors listen to them.

2. doctors who investigate and research conditions to find causes and solutions....this is when conditions get discovered and effective treatments get

Sadly for us lot the big endos in the sky pulled their shutters down and refuse to review their protocols for not only diagnosis but effective

I wasn't on any thyroid meds for several years though i felt soo ill. it was only when my TSH blood test tipped up by 0.1 that they finally diagnosed me -amazing what 0.1 can do! i was quite sarcastic with the doctor about it as it seemed so ridiculous to make such a fine line in diagnosis....but you know those protocols rule!

And once diagnosed i only got well when I went private....

Anyway look at the vitamins D Council website -the advise 5000iu of D3 as a safe level -but you shoudl get your bloods tested periodically for D3.

The b12 -well i wasn't technically deficient -perhaps a little low so i was really surprised that it made such a difference -i take Jarrows Sublingual -if you loo at my other posts your see more info. And avoiding the grains ( rice included) seems to keep me clear thinking and more energetic, helps with control of weight (but still an issue if not guarded x

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Hi Everyone,

I didn't know this but I have noticed that when we have a sunny day I seem to feel better. I still have all the hypothyroid symptoms but my mood seems better. Perhaps the Vitamin D from the sunshine is helping my TSH levels. I'm now on 75mcg of Levothyroxine but this dosage does not feel right and I think I should be on a higher dose. My endo surgeon wants me to wait and see because my TSH is now 2.17 although I know it should be <1 to ensure that the thyroid cancer doesn't return.


I am surprised that your surgeon is playing a wait and see game, because as you rightly say your TSH should definitely be suppressed.


Hi Marram,

Thanks for replying to my post.

I think the specialists feel that my left thyroid lobe should start doing the work of both lobes but I know that this is not the case. From the information I've managed to glean I think I've been hypothyroid or have been sub clinical hypothyroid for some years. Now I know the symptoms of hypothyroidism I know I've had some of them for many years, these being, itchy dry skin, tiredness, lack of energy, irregular periods (I thought I'd started the menopause early), weight gain, raised cholesterol, tingling in my hands and feet, digestion problems etc. Unfortunately, when I've raised my concerns with the GPs I've been told that I cannot be going through the menopause too young, itchy skin is eczema, weight gain you're fat and then following blood tests I was told I was diabetic. I believe now that hypothyroidism causes raised cholesterol and weight gain and these contribute to diabetes. When I queried my hormones I was told they were normal and within range but I now have them and my TSH was in the upper range of normal and considering I had thyroid cancer then this would cause raised TSH because the cancels cells make thyroid hormones. Now that the cancer has been removed I am most defo hypothyroid and this was confirmed to me by the endocrinologist a couple of weeks ago.

Anyway, I hope that I get sorted soon as 75mcg Levothyroxine isn't make a difference with my symptoms.


From your links- it appears that for older people [likely to have Thyroid issues] this is not proven

The study in Thailand ONLY found the reduced TSH with higher Vit D in the lowest 1/3 of age range -ie: those starting at age 15 and upwards.

The second study [Amsterdam] showed no matching activity with Vit D and autoimmune thyroiditis.

I would be pleased to learn that Vit D can help with thyroid problems, as if so,it's an easy check on illness progress, but would still need monitoring -as too much D is not good.

A serum figure of around 70 [nmol/l] seems to be an optimal minimum.


I don't know whether I dreamt it, but thought that Vit D is linked to calcium production and calcium levels should be checked before starting Vit D.

Was this a dream?


You may have dreamt that but you are correct. Too much calcium bad for kidneys. Calcium levels must be checked before taking vit D with calcium. Otherwise Vit D 3 on it's own. With regard to ranges : results of my Vit D range 50 - 250 mine 54. So, OK, within range, at the bottom end. No suggestion from either GP or Endo to get a supplement. Well I did. Certainly there has been an improvement with the brain, B12 range was 250 - 945 mine 635. So, ok again within range but a long way off being the optimum level. We do have to look after ourselves. GP's have insufficient knowledge on certain things. At the end of the day, what we have seems to be a very specialised condition with too many variances.


Thank you Snowstorm, thats where I have been getting confused. Didn't know some Vit D came with calcium. So presumably if my Vit D levels are low it will be okay to supplement with Vit D only without testing my calcium.

You are right about GP's, asked for iron to be tested because of my dizziness, along with other things, and was totally ignored. Was however, offered statins, they would do the trick no doubt!! Declined by the way.


I think VitD enhances Calium uptake into bones- hence its implication, when lacking, in Rickets.

Taking D without blood test is not advisable long term.

Many sites say 4000 iu per day is safe -and even necessary for many, but it is better to know each individuals case by testing every few months.

It also takes time for levels to stabilise.

I take 1000iu some days [with K7] at my tested D level of 60 - but this is probably not enough.

I will test again though and seek better serum level of 70+ when I know more about my situation.

Moderate sunlight exposure is the best self regulating way to get D and provides quite large boosts within the feedback mechanism of the body.


Your very welcome. x


I believe vitamin D is known to affect the immune system. And one of its affects is to reduce autoimmunity.


Sure does -low vitamin d levels effects one's abilty to fight of infections.....also lack of vit d can contribute to weight gain as it affect the metabolism....


I googled the phrase vit d lowers tsh and found your thread.

I got my vit d3 and tsh results today. I was excited to see that my tsh fell from 9.33 to 5.37. Only thing I did differently is take 5000ius of vit d3 every few days. Im going to take it every day and see what happens!


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