Vitamin D tablets

Hi I take 800iu D3 tablets for vitamin D deficiency found in 2013. These weren't helping my levels rise so I started taking 6000iu which got me into suboptimal range. My doctor told me I had to take the 800iu as they prescribed me or they will stop prescribing it if I am taking 6000iu which they say is toxic. Any idea what to do please?


25 hydroxy vitamin D2 <6.0

25 hydroxy vitamin D3 38.8

Total 25 OH vitamin D 38.8

(25 - 50 vitamin D deficiency supplementation is indicated)

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10 Replies

  • Felicity,

    I would ignore your GP and continue treating yourself. If 800iu was adequate your vitD wouldn't still be insufficient at 38.8 4 years after supplementing.

    6,000iu isn't a toxic dose. My GP prescribed 40,000iu daily x 14 followed by 2,000iu daily x 8 weeks which raised vitD from <10 to 107. Your GP should refer to local guidelines or the NICE CKS recommendations for treating vitamin D deficient adults

    Vitamin D should be taken 4 hours away from Levothyroxine and T3.

  • Felicity1 What to do? Take things into your own hands!

    Doctors know nothing about nutrition as they aren't taught it, so we have to learn to help ourselves.

    You have been deficient since 2013 and have been taking 800iu daily. After 4 years your current level is 38.8nmol/L (I am assuming you are in the UK). So you can see that 800iu daily hasn't exactly helped! So let your GP stop prescribing and help yourself from now on. I got mine up from severely deficient at 15 to 200 in two and a half months and I didn't even bother with my GP.

    The recommended level for Vit D is 100-150nmol/L.

    You can read through the Vit D Council's website for further information, this page takes you to an explanation of results and what dose is recommended to achieve different levels. It is in ng/ml and to convert that to nmol/L you multiply by 2.5. So 40-60ng/ml is the same as 100-150nmol/L - the recommended level.

    I think the Vit D Council knows more about supplementing with D3 than your GP.

    My suggestion is to buy some D3 softgels like these

    and take 10,000iu daily for 6 weeks then reduce to 5000iu daily. Retest after 3 months. You can do a private fingerprick blood spot test for £28 from City Assays

    When you have reached the recommended level (100-150nmol/L) then reduce to 5000iu alternate days as a maintenance dose. We all differ in how much we need as a maintenance dose, and maybe less in the summer if we get out in the sun. We have to find our own specific maintenance dose. When supplementing with D3 it's recommended to retest once or twice a year to keep within the recommended level. And supplementing is for life.


    When taking D3 there are important cofactors needed which you can read about here

    D3 aids absorption of calcium from food and K2-MK7 directs the calcium to bones and teeth where it is needed and away from arteries and soft tissues where it can be deposited and cause problems.

    D3 and K2 are fat soluble so should be taken with the fattiest meal of the day, D3 four hours away from thyroid meds.

    Magnesium comes in different forms, check here to see which would suit you best and as it's calming it's best taken in the evening

    Check the other cofactors too.


  • Yes I am in uk and I have a magnesium spray but not MK7 K2 thankyou

  • Yep, as Seaside says, Vit K2 Mk7 is important. Very important. Vitamin D helps you better absorb calcium and K2 directs the calcium to the skeleton, rather than leaving it to lurk in arteries, causing calcification. Amazon is where I get mine from :-)

  • Oh my days - completely ignore him!

    Print off the NICE guidelines in the link above as this is what GPs are supposed to follow and this quite clearly states that loading doses are required fo those with severe deficiency and to only then go onto 800iu maintenance dose. Your doc has simply given you the maintenance dose. Shove this in front of docs face next time you see them!!!!

  • Highly unlikely, assuming you have Hashimoto's, that a maintenance dose will be enough, even after you have had loading dose to get vitD to good level.

    With autoimmune diseases, we need or use more, or can't make enough.

    Have you had folate, ferritin and vitamin B12 checked, if not ask GP to do so

    If you have Hashimoto's (high antibodies) then changing to gluten free diet is definitely worth trying. Majority of us with Hashimoto's find it really helps.

  • Yes I have hashimotos but told to eat gluten for celiac test

  • About 80% of us are gluten intolerant, only about 5% diagnosed as coeliac

    Have you got a date for endoscopy if you are doing gluten challenge

    Gluten very likely trashing other vitamins

  • No date for endoscopy yet

  • Where do they get these ideas from - toxic my a***e? I'm no expert but have read a lot about Vit D for a friend who has MS. As far as I recall all scientific studies have shown that Vit D does not produce toxicity at any tested level, the only concern is the deposit of calcium in the arteries or kidneys with supra physiological doses. Look at the work of Dr Coimbra who has been successfully treating autoimmune diseases for years with high doses of Vit D. My private doctor advised 5,000iu per day; Dr Coimbra recommends 10,000iu per day as a standard dose. His patients receive 200-300,000iu per day with no toxic effects. He calls the 600iu recommendation in this country 'paltry' - which it is. (I'm not medically qualified so do not rely on my post but do check out the internet as at the moment there are many studies into Vit D.)

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