Vitamins and minerals - Vitamin D 

  • Overview

Vitamin D 

Vitamin D has several important functions. For example, it helps regulate the amount of calcium and phosphate in the body.

These nutrients are needed to keep bones and teeth healthy.

A lack of vitamin D can lead to bone deformities such as rickets in children, and bone pain and tenderness as a result of a condition called osteomalacia in adults.

Good sources of vitamin D

We get most of our vitamin D from sunlight on our skin. The vitamin is made by our body under the skin in reaction to summer sunlight. However, if you are out in the sun, take care to cover up or protect your skin with sunscreen before you turn red or get burnt.

Vitamin D is also found in a small number of foods. Good food sources are:

  • oily fish, such as salmon, sardines and mackerel
  • eggs
  • fortified fat spreads
  • fortified breakfast cereals
  • powdered milk

How much vitamin D do I need?

Most people should be able to get all the vitamin D they need by eating a healthy balanced diet and by getting some summer sun.

Groups of the population at risk of not getting enough vitamin D are:

  • all pregnant and breastfeeding women
  • babies and young children under the age of five 
  • older people aged 65 years and over
  • people who are not exposed to much sun, such as people who cover up their skin when outdoors, or those who are housebound or confined indoors for long periods
  • people who have darker skin such as people of African, African-Caribbean and South Asian origin

What does the Department of Health recommend?

The Department of Health recommends:

  • all pregnant and breastfeeding women should take a daily supplement containing 10 micrograms (0.01mg) of vitamin D to ensure the mother's requirements for vitamin D are met and to build adequate foetal stores for early infancy
  • all babies and young children aged six months to five years should take a daily supplement containing vitamin D in the form of vitamin drops to help them meet the requirement set for this age group of 7-8.5 micrograms (0.007-0.0085mg) of vitamin D a day 
  • babies fed infant formula will not need vitamin drops until they are receiving less than 500ml (about a pint) of infant formula a day, as these products are fortified with vitamin D 
  • breastfed infants may need to receive drops containing vitamin D from one month of age if their mother has not taken vitamin D supplements throughout pregnancy
  • people aged 65 years and over and people not exposed to much sun should also take a daily supplement containing 10 micrograms (0.01mg) of vitamin D

You can buy single vitamin D supplements or vitamin drops containing vitamin D (for use by under-fives) at most pharmacies and supermarkets. Women and children who qualify for and already participate in Healthy Start can get free supplements containing vitamin D.

See the Healthy Start website for more information about the scheme.

What happens if I take too much vitamin D?

If you take vitamin D supplements, do not take more than 25 micrograms (0.025mg) a day, as it could be harmful. However, taking less than this is unlikely to cause any harm.

Your body doesn't make too much vitamin D from sun exposure, but always remember to cover up or protect your skin if you are out in the sun for long periods.

Taking too many vitamin D supplements over a long period of time can cause more calcium to be absorbed than can be excreted. 

The excess calcium can be deposited in and damage the kidneys. Excessive intake of vitamin D can also encourage calcium to be removed from bones, which can soften and weaken them. 

Page last reviewed: 26/11/2012

Next review due: 26/11/2014


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The 29 comments posted are personal views. Any information they give has not been checked and may not be accurate.

User865095 said on 15 April 2014

I actually became quite angry reading this article for the reason john88 gives below. I was diagnosed with what I presume was quite a severe vitamin D deficiency a couple of weeks ago (I was prescribed 20000 iu daily for a week then one tablet weekly), and - on reflection - this didn't come as too much of a surprise to me (though a relief as my main symptom was musculoskeletal pain in the left of my chest).

This is because my work has meant that for quite some time I've not been exposed to a great deal of sunlight and I'm based in northern England. Thing is, I read the RD-blasted-A for SUPPLEMENTAL vitamin D (all sunlight is bad - right?) and figured that my levels must be fine. What BS! Why-oh-why must official advice err on the side of caution to such an extent as to potentially undermine the general health of society?! Is it just a reflection of its becoming increasingly litigious? Were it not for the grossly misleadingly low recommended levels I'd have diagnosed my condition myself years ago!

The evidence implicating vitamin D3 deficiency in MS, for instance, staggered me (Iranian revolution; women clothed from head to toe; rates increased eightfold; much more). This is SERIOUS. Why can't the UK treat people more like grown ups in this respect (and why are US sites so much more informative)? I realise money isn't made out of natural compounds which cannot be patented (and there must be a lot in sunscreen) but please stop treating people like morons. I have it on good authority (a GP told me) that the recommended (that word again!) alcohol limits were basically made up because the government wanted a figure and so a ridiculously low amount was plucked out of thin air. Enough!

Oh, and please be consistent with units - either iu or mass. I realise iu reflects biological effectiveness but as this changes on reassessment simply change the recommended(!) level.

If you're in northern Europe (especially if you're not Caucasian) get your levels checked!

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Annejam said on 13 February 2014


I have just read The Vitamin D solution by Michael Holick. It answers a lot of the questions posted below.
He has a website, where you can hear him lecturing on Vitamin D. He has studied the subject all his life, and is considered to be a world expert on the subject.
Hope it helps.

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john88 said on 29 January 2014

Hello to everyone and good health. After some research i have come to the conclusion that the RDA
( Recommended Dietary Allowances ) for Vitamins has been set far too low. The RDA has been set so low as to negate any real beneficial effects of Vitamins. The reasons why the RDA for Vitamins has been set so low is a fascinating and eye-opening subject to do a little research on. Please, Please dont take my word for it. Just spend a little time to research the sublect of - RDA for vitamins is wrong. Vitamins are extremely beneficial to good health. Taken in appropriate amounts ( not the very low RDA amounts ) and combinations will aid health so much.
The best of health to everyone - Thanks

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Anonymous said on 27 July 2013

I've recently been diagnosed with Primary Hyperparathyroidism. My blood calcium was 2.69, which raised the alarm in the beginning and this was only found by chance when I was being tested for celiacs disease. (Had lived with so called IBS and as no IBS medication ever worked I asked my GP for these food allergy blood tests)
My vitamin D levels are low due to this condition (unsure exactly how much) The consultant endocrinologist wrote to me and advised me that I must see my GP so that he could prescribe Vitamin D ONLY, which he did, on prescription, Pro D3 10,000iu one capsule a day. I have bone pain and exhaustion and also feeling quite low, mood wise. I've gained weight too. Normally an active cannot sit down type of gal.
My concern is, because my parathyroid isn't managing my calcium as it should, I have read and done much research on this regards the condition (primary hyperparathyroidism) and unsure at this stage as to when the surgery will be, will my calcium raise? Last blood test was normal but urine showed calcium excretion. The consultant doesn't see any great urgency at this stage. I do have an appointment arranged for the bone DEXA scan in a weeks time.
Thank you. I do hope that someone out there will be able to answer the above question regards hyperparathyroidism verses vitamin D supplements, good or bad?!

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ShrutiP said on 07 April 2013

Yours is the most comprehensive information that I have found on vitamin d deficiency..which I was diagnosed of 2 days back...mine is 14ng/ml, my doctor has put me on a medication plan of 1 liquid gel capsule 60000 IU once a week and a calitrol,calcium,calcitroland zinc capsule daily for 2 months.I did ask her about retesting my d3 levels later but she says it's not required...of which I'm not convinced.Now let me tell a little about myself n how I came about to get my levels tested...I'm an Indian , 33 yrs.old and female I had been having this dull ache in left arm on and off for the last decade or so! :o this pain started as a numbness in the thumb and forefinger when I used to do some crocheting,it used to go away when I stopped crocheting later it became a nagging ache in my left arm( I was worried that it was something to do with my heart to which the doctor told me there was nothing wrong with the heart but it was a postural problem and prescribed me some vitamin e and calcium suppplements-he aws right I used to sleep on my left-side putting a lot of body weight on my left shoulder and arm once I corrected this the pain went away. After having my child who is now 3 3 years old. my condition resurfaced as D e Quervain’s syndrome and I also got cervical spondylosis…since then things have gotten from bad to worse, I get cramps and sprains easily and for the last 6 months or so have knee and ankle pain…also hair loss and mood swings…my TSH and Heamogram are normal so was my B12 level when tested some time back.I want to know if the nedicine prescribed to me is in correct dosage and for the right duration also what would be the correct follow-up. Can I supplement it with light exercising etc. safely? My ankles have been swollen for the last 2 weeks could it be due to vit. D? I also have been having frequent episodes of tummy upsets and bloatiness over the last 6 months are they related?

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Sachabloke said on 23 March 2013

Note this study that prescribes 50mcgs or 2000ui of vitamin d per day for beneficial effects which is twice the amount NHs guidelines prescribe.

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Dave 2409 said on 16 January 2013

Why cant vitamin D doses be expressed in ug measurements ? a well, its always iu or mg... I see most over the counter Vit D sold in ug.

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RandomStar said on 09 January 2013

I case you read crofter56 comment mg stands for milligrams, not micrograms normally shown as ug. There are 1000 micrograms in 1mg. Take 10 micrograms or 0.01mg a day and dont take more that 25 micrograms /0.025mg.


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Sunshineonarainyday said on 01 January 2013

Two years ago (winter 2010) I was very run down, tired and aching all the time. Test showed my Vitamnin D level was 28 (did not mean to me!) I was prescibed Vit D but also had a couple of holiday in the sun. Last winter (2011) I was okay and managed through winter. In 2012 I have had no holidays abroad (and the UK has been particularly awful!) but as I am taking Vitamin D supplements everyday I thought I would be okay. But I am shattered and aching again. I am wondering if i am not absorbing it properly. Has any one any information on anything that may stop the absorbtion of Vitamin D supplements and also how long the body can store it?
Thank you

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crofter56 said on 14 December 2012

No wonder people get confused... just how many ways are there to measure a unit of vitamin D..... just a simple table with recommended amounts is all that is required as long as it relates to what is on the packaging.... ui mg come on make it user friendly..... even the article is confusing tells us we need 10 or 5 mg a day and then tells us to take no more than 0.025mg......... and states micrograms in one part and mg in others how many people in the street will know this is the same....then there is ui... oh i give up!

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tr1ck5t3r said on 09 December 2012

Part2. If anyone is to take high doses of Vit D supplements (10,00ui or more per day), D3 is the best form and natural to humans, D2 is the planet form like mushrooms exposed to UV-B and is toxic at lower doses than D3. However just because you take D3 supplements doesnt mean its working properly, you also need magnesium, you see every cell in the body is comprised of magnesium and it would be a massive understatment to say its not that important, it is very important and we get it from eating our greens, chlorophyll the substance which makes plants green is high in magnesium but is very water soluble. Due to the processed foods we eat today, the intake of magnesium is seriously reduced in the western diet which leads to many different problems (because we are complex organisms not single cell organisms), but if you take a magnesium supplement, some forms will give you diarrhea. If this happens, crush the supplement up into very fine powder, mix in water and consume periodically throughout the day, in other words avoid a big hit of magnesium in one go. Mag Oil on the skin will work just as well, just adjust the magnesium concentration to suit, as highly concentrated it can sting the skin until people get used to it, or do like I did, fill the hot tub with kilos of magnesium chloride or take Epsom Salt baths with 600grams of Epsom Salts (Magnesium Sulfate) in the bath. If people take a high dose supplement of Vit D3 and experience muscle cramps or aches, this can indicate low levels of magnesium so a magnesium supplement will help. Other useful info, total and free testosterone production is linear when Vit D levels (25(OH)D) are below 75-85 nmol/L and reach a plateau at high levels.

The is also a good source of info with info in easy to understand form, but for more technical info, is useful as are other sites.

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tr1ck5t3r said on 09 December 2012

The units of measurement mentioned above ie mcg do not relate to the unit of measure most people will see when looking for a Vitamin D3 supplement. So here it is: 1 mcg = 40 IU of vitamin D, and another useful conversion is 1 nmol/L = 0.4 ng/mL taken from

You might see statements suggesting 30minutes of whole body exposure to sunshine will generate between 10,000ui-20,000ui, but what is not stated is the strength of the sun often dictated by latitude, the low level o-zone from vehicle pollution reacting in the sun (because o-zone blocks UV-B) and also consider humans used to be outside alot more than todays society and work regime allows. If people are interested in getting their levels checked, a simple bloodspot test sent in the post can be ordered from the NHS here . I prompted these guys to issue the statement on their lab reports "Total vitamin D levels above 220 nmol/L are considered ‘High’ and increase the risk of vitamin D toxicity" because as an experiment, I sat outside with my top off working on my laptop for most of Aug 2012 not far from Cambridge to see what my levels would be. The result came back at 229.7 nmol/L and I'm a middle aged Caucasian Skin Type III, darker skin people in the UK would need more time. It should be noted melatonin (the skin pigment that gives us our suntan) converts 99.9% of the UV radiation into heat so we have my own natural sunscreen just dont burn. I also only use sea salt to wash in so I dont strip my skin of essential oils, as one study showed showering immediately after sunbathing showed a reduction in the Vit D in those individuals, so it quite likely to our skin oil is the first part of the process often referred to as the skin generating Vit D. The Wellcome Trust state there are 2776 Vitamin D receptors in the human genome, most concentrated around the immune system which boosts it hence the benefits.

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Donald5 said on 05 September 2012

I don't understand the problems people are reporting with with access to vitamin D3. I have in front of me a bottle of D3 25ug from a local health food shop. A well known national chain! I live in Scotland and it has been suggested to me that as the winters here are longer and darker than south of the border that taking one of these a day is a good idea. I have done my research after reading recent articles. Not very scientific, I suppose but if the advice the NHS is giving GPs seems rather slow on the uptake then what is one to do?

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Emmanuel Yannikakis said on 18 June 2012

The important message here is get yourself and your family tested for Vitamin D the test is called 25(OH)D, doctors have in the past basically ignored it due to the NHS guidelines set out for them.

if like myself you are defiecent ask your doctor for a high dosage of vit d3+ vit k1(eat green veg)+ k2 (do not supplement if you are on blood thinning med) over the counter 200/400 iu/day will not make a differance, even with a high dosage it can take 3-5 months to top up.

The DoH has to start trials as more information is connecting Vit D3 and a host of disease prevention from seasonal infection to possibly modifying cancer cells, can you imagine if this is correct how much pain and suffering will be reduced and what a saving for the NHS funding: Insufficient vitamin D levels in CLL patients & Cancer
Link - Mayo Clinic Vitamin D insufficiency predicts time to first treatment (TFT) in early chronic lymphocytic leukaemia (CLL). Vitamin D status has a linear association with seasonal infections and lung function in British adults Study: Vitamin D Kills Cancer Cells - ABC News Up to 10000 iu per day as safe

Due to the lack of trials on cll (leukemia) and vit d3 I have started my own self imposed trial of 10000 iu/day d3 for 100 days ends end of july - do not do this ask your doctor for advice.

The drug companies will not do trial test with vit d there is no money to be made - my mega dose cost <£13 for a 6 month supply.

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isopops said on 07 June 2012

Hm, interesting discussions. I have a box of "Pro d3 20, 000iu " vegecaps sitting in front of me which I received on prescription from my doctor following blood tests showing I was deficient. She had to ring up the drugs advisory group to find out what to prescribe me as the regular tabs are not suitable for nut allergy sufferers, and then my pharmacy had to order them in especially. But it is perfectly possible to get Vit d3 on the NHS. I don't understand why people would struggle.

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megaFedUp said on 01 June 2012

Absolute rubbish. You can be prescribed vitamin D3 but doctors are told to use that excusesoley to save money.
I went into boots and they confirmed that anything that is precribable can be ordered. Including vit d injections.
Vitamin D ois not on their 'banned' list.
I told the doctor who then phoned his local boots and told them that if anyone asked, tell them they do not stock it.
It is on their shelves......
I am severly dificient. I do not work. I am a pensioner. The doctor is expecting me to give up food and to buy these tablets at the levels I need.
They can be prescribed - if you don't believe me get an honest answer from any chemist and if you push them, they will trell you the truth.

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nicolette22 said on 01 June 2012

Hi Sally - you mention in your last post that you had a special interest in osteoporosis? Hence my post to you....ive got osteopenia and am vegan aswell as maintaining a very low BMI for over 17years. Ive resisted taking vitamin d and calcium due to them not being vegan and ive heard that vitamin d and calcium and magnesium and even MK7 form of K2 all contribute to increasing bone density.

Next....i understand that calcium and vit d go hand in hand when it comes to being absorbed by the body, so essentially if i am taking a calcium supplement then regardless of how much sunshine i get - which even in the summer i cover up or dont go out anyway, should i still get a daily dose of vitamin d supplement? Or do i only need to get this in the winter (and take the calcium on its own in the summer - would the vit d be stored in my body and thus help absorb the calcium id be taking in the summer?)

But there are products out there that contain 5000mcg? This sounds an awful lot per day. Would it be as effective if i took this just once a week? and took my calcium, magnesium and k2 everyday still? Would the vit d be stored in my body so to help the other minerals be absorbed?

If i had vitamin d in a multivitamin and so had it in my body...and then took a calcium and magnesium supplement and another mk7 tablet, would this essentially have the same effect as if i had taken all four together in one combined tablet? Or does it not work like that?

Well thanks very much indeed for your time and i do very much look forward to hearing from you soon,

Kind regards,


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thepostnatal said on 02 March 2012

All information is very useful.. but you can see more information on
Thank you..

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Akkenru said on 13 February 2012

Vitamin D is the new vitamin C?

What nonsense are you guys posting?

You can't get vitamin C any other way than through eating it and it is essential to several biological processes, and it is a useful anti-oxidant.

Vitamin D you make in your skin when stimulated by sunlight and it functions to balance your calcium levels and uptake. Sure, there are many knock-on effects from calcium imbalances as a result of vitamin D insufficiency or deficiency, but vitamin D is not essential to any known biological process.

How on earth can you compare two vastly different vitamins (vitamin D is fat soluble and can be stored, vitamin C is after soluble and can't be stored), calling one the new version. This is completely ridiculous and highlights a massive problem with society nowadays. People get the tiniest inkling of a bit of information and they think they know everything about it and start giving advice about what's best to take, when they actually know so little they may as well be advising others to take arsenic. Albeit with the best intentions but your advice is poor, insufficient and doesn't take into account the bigger picture.

Advice like this causes more problems for people's health than if the situation were left alone. If you find that your vitamin D is insufficient or deficient then you've clearly been to see a doctor to get the blood test done, follow their advice and avoid damaging your liver and kidneys with public hype.

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CaraTee said on 09 February 2012

@neerual & @gedboy You can buy a Vitamin D3 oral spray that is D only. I've seen it in some Health shops (D-Lux) and a Vegan version if you are that way inclined (Vitashine) I've seen them on amazon and other online shops.

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caliwag said on 24 January 2012

I have been following Dr Briffa since his excellent Observer days...sometimes on R4

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neerual said on 11 January 2012

this question is for LeungB. what are the vitimin D supplements called that you got from health shop. i am looking for some for my grandchildren who live in scotland, aged 1years and 6 months and 4 years and 6 months. i have scoured the internet and cannot find them on there own.

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LeungB said on 07 December 2011

I was prescribed AdCal (D + calcium) 6 months ago, then I have my blood test. Calcium level is ok but still low with vitamin D. My GP did say the NHS do not prescribe vitamin D on its own and told me to buy it from health shop. I left the surgery and visited a few chemists, they don't sell vitamin D on its own. Just before I gave up, I went to a high street health food shop, there they are, Vitamin D at quite a reasonable price. Hence Sally Hope, if you are still looking for vitamin D, go to a health food shop.

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User617891 said on 21 November 2011

Believe it or not, most people are deficient in Vitamin D. Lack of Vitamin D can cause some cancers and lots of other diseases. I have been doing plenty research on this. You can get natural "D", by going in the sunlight 15 min per day, 3 times a week, and get it in dairy products. Also, especially for women, take a calcium supplement with Vitamin D, the D helps absorb calcium better. I promote to all, get your vitamin D....very very important. It used to be,,,,take the vit. c, for immunity, and that is true, but D, is a must.

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User617891 said on 21 November 2011

Believe it or not, most people are deficient in Vitamin D. Lack of Vitamin D can cause some cancers and lots of other diseases. I have been doing plenty research on this. You can get natural "D", by going in the sunlight 15 min per day, 3 times a week, and get it in dairy products. Also, especially for women, take a calcium supplement with Vitamin D, the D helps absorb calcium better. I promote to all, get your vitamin D....very very important. It used to be,,,,take the vit. c, for immunity, and that is true, but D, is a must.

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hambakahle said on 17 November 2011

If you are vitamin D deficient you can be prescribed colecalciferol 20,000 units taken twice weekly x 36 tablets. Check calcium and vitamin D after 3 months.

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MissEm said on 16 October 2011

To Sally Hope,

I think you may be mistaken because I have just been prescribed a vitamin D supplement on the NHS - colecalciferol

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Azazel said on 12 October 2011

To gedboy, yes vitamin D can be got by its self, FSC mmake vitamin d3 in doses of 10mcg (400 i.u), put it in google and buy online. Only buy vitamin d3, as vitamin d2 does not do much. But dont over do it, at the moment vitamin d is the new vitamin C, its been sold in very high doses and its hard to find websites that dont reccomend massive doses. I came here today to find information that wasnt aimed at selling something. Some are saying to take 2000-4000 i.u of viotamin d for variouse medical conditions, nhs are saying 25 mcg (1000 i.u) max. The rda for vitamin d is only 200 i.u and in america its gone up from 400 i.u to 600 i.u for older adults who dont get much sun. This increase had lead to all the hype.

Vitamin d is not like vitamin c, an high dose does not pass out in the urine, it stays in the body and will cause dammage to the system by causing calcium to deposit in soft tissues if large doses are taken over time. If you choose it then stick with 200-400 i.u and dont fall for the hype. If you carnt get a lower dose tablet then break it in half or take it every other day.

I have SAD and i take low dose vitamin d alongside light therapy in the winter months, but reciently i have been tempted to try megadose vit d myself but have looked about for information to see if its something i want to do long term and i have decided not. There is no way to know how much vitamin d the body has stored over the summer.

Im not a doctor, or medical person, i have a biology degree though.

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gedboy said on 11 October 2011

I am looking for Vitamin D for my partner who has ME. Amazingly it cannot be bought unless it is with calcium or is a multivitamin. Her doctor is quite specific that she mustn't take the calcium enriched tablets. The pharmacist went through his book (pharmacopeia?) and could not suggest a solution. Where then to go?

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