Vitamin D

Does it work? Yes, if vitamin D deficiency causes or contributes to your pain. I've heard people say boosting their vitamin D helped them. I don't think it made any difference to mine, but when the doctor tested my blood I was found to be vitamin D deficient and therefore started taking supplements. Vitamin D deficiency is generally bad for your health and in particular also means you're likely to be deficient in calcium because the body needs vitamin D to absorb calcium, so I now take it regularly anyhow, as, among other things, the same blood test showed I had low calcium levels despite eating a large amount of dairy. The way I look at it, I have enough problems already without adding calcium and vitamin D deficiency into the mix, so I'm going to keep taking it.

What is it? It's a vitamin. It's that one our bodies make from sunshine, although we also obtain it from some foods, such as oily fish and eggs. The sunshine link means that a lot of people who live in the north of the northern hemisphere or the south of the southern hemisphere are deficient in it, at least during the winter and spring months, and especially if they don't spend much time outdoors with their skin exposed to the sun (with or without sunscreen) and/or have a darker skin colour.

Who does it work for? People with a vitamin D deficiency if that's contributing to or causing your pain. In particular, that seems to be people whose symptoms include non-specific musculoskeletal pain, headache and fatigue.

Who doesn't it work for? People whose pain has nothing to do with a vitamin D deficiency. Doctors can give you a blood test to test if you're vitamin D deficient, but they can't test whether it contributes to your pain. You can test it for yourself by trying taking it for a few months and seeing if you notice a change. This is not entirely scientific, as you're unlikely to be able rule out other causes of changes in your pain, but I think it's worth a try and the nurse at the centre of pain education recommended that all of us get tested for vitamin D deficiency and take vitamin D supplements if we were low on vitamin D.

 
Where can I get it? From a pharmacy or a health food shop or online.

How much does it cost? The one I bought cost £12.99 for 360 daily pills, so that's around £12.99 per year. You can get smaller quantities for a lower price if you wanted to try it for a month or two to see if it helped. Some sellers charge significantly more, for instance £4.50 for 30 pills. Don't forget to check both the number of pills in the pack and the level of vitamin D each pill contains. I find similarly sized packs often contain massively different numbers of pills.

How much of it should I take? The NHS recommends taking a supplement of between 0.01 mg and 0.025 mg per day. Vitamin D is often measured in international units (IU). According to this website, 5,000 IU is equivalent to 0.125 mg, which means that at 5,000 IU I'm taking five times the absolute maximum the NHS recommends per day (i.e. 1000 IU), which means it's probably a good thing I don't remember to take it every day. On the other hand, Web MD says I should be taking between 600 and 4,000 IU per day. My guess is my NHS doctor would recommend the same as the NHS website. Overall, it looks like 5,000 IU is rather on the high side and I should look for a dose of 1,000 IU next time, such as this one.

There's more than one sort of vitamin D, which one should I take? According to Wikipedia, in humans the most important vitamin D compounds are vitamin D3 (cholecalciferol) and vitamin D2 (ergocalciferol). According to an NHS source I found, vitamin D3 is the preferred one for treating vitamin D deficiency. (I in fact found several websites that said vitamin D3 is the right one to take, but the NHS one was the first where I was sure I could trust the source.)

Is there any evidence for it? Yes, but as is so often the case, the studies seem to show mixed results. Some studies say yes it works, others say no it doesn't. What they do seem to agree on though, is that vitamin D deficiency is prevalent in chronic pain sufferers, so the very fact you suffer from chronic pain may be enough reason to get yourself tested or even just to take it as a supplement without getting tested.

  
Are there any downsides? Not really. There's the relatively low cost (about £1 a month), but actually, if you have a vitamin D deficiency, even if it doesn't help you with pain, it should help you avoid other health problems. However, excessive vitamin D levels can be bad for you. If you are in any doubt at all, speak to your doctor either about getting a vitamin D test or about whether there is a sensible and safe level of vitamin D you should take without even knowing your vitamin D level.

Are there any other upsides? Yes, not having a vitamin D deficiency is generally good for you, and having a vitamin D deficiency can lead to all sorts of health problems.

Was it worth the money? For me, it wasn't worth it for the pain effects as it didn't seem to have much effect on mine, but it is worth taking so I don't suffer from the other health problems a vitamin D deficiency brings.

Have you successfully reduced your pain with vitamin D? How quickly did you notice a difference and what difference did you notice?