Does Vitamin D Deficiency Cause or Contribute to Rheumatoid Arthritis?

Recently, after months of rain and miserable damp weather here in Manchester, I started to develop a bit of a wheeze in my breathing, a few days later I developed asthma; something I have not really had since my teens. I know from experience that in my case it is linked to humidity and mold spores in the damp air, but it’s been so long since I had asthma I wondered why it had returned now.

After a little research and some head scratching (‘thought’ not lice!), I concluded that it must be due to the excessive recent humidity, my current work load (stress and insufficient sleep) and the fact that I’ve been straying from my RA diet over recent weeks and starting to experience a few mild symptoms (maybe I had become a little more sensitive to allergens).

Vitamin D – Rheumatoid Arthritis – Asthma – and My Work!

Whilst I was researching I came across a report describing a potential link between asthma and vitamin D deficiency. After reading through the report it did occur to me that I’ve been working long hours ‘inside’ in front of the computer, either on-site, at my office or at home. Also, because of the dismal weather I haven’t been out much at weekend, and on top of that I also stopped taking cod-liver oil a few months ago for an unrelated reason.

It did seem like a possibility that a lack a of vitamin D may have helped to cause the recent return of my asthma. I was intrigued and continued to research the vitamin D link.

Now the interesting bit from an RA point of view; I started to come across reports and articles which also linked vitamin D deficiency to rheumatoid arthritis – something I had not read about previously other than the general need for vitamin D for healthy bones and its link with calcium absorption.

So, before writing this post, I read every article and paper I could find on this vitamin D link and I’ve included links to the most interesting and noteworthy of them, along with my own summary below.

Rheumatoid Arthritis and Vitamin D Deficiency – The Link

Everyone knows these days that vitamin D is important for bone development and health, and also of its importance in helping to prevent rickets (here’s an interesting parallel link in the Guardian discussing vitamin D deficiency and rickets in kids spending too much time playing computer games).

It makes sense for anyone with RA to make sure they receive enough vitamin D (in my case using a D3 supplement with an extra virgin olive oil base) of course, but I wasn’t aware of the research linking RA (and other forms of arthritis) more directly with vitamin D deficiency.

The research and subsequent reports are based on various tests and trials including a fair amount of subjective data collection via patient form filling. However, it is still compelling and appears to reveal a number of interesting facts.

• Rheumatoid arthritis sufferers tend to be deficient in vitamin D.
• The severity of pain and general disability is inversely related to the level of vitamin D deficiency (possibly related to calcium absorption which is a natural pain killer and relaxant – after all vitamin D is also known as calciferol).
• Vitamin D has a beneficial effect as an immunosuppressant.
• People with a higher intake of vitamin D had a lower risk of developing RA.

Also, there are a number of people (including doctors) who are promoting the use of vitamin D supplementation as either a possible cure for rheumatoid arthritis or as a method of significantly reducing symptoms. The proponents of this idea suggest using a much higher dose than the typical 200 to 400 UI per day recommendation. They suggest a dose of 4000 to 6000 UI per day.

I am very interested in this and I am going to give this a try for a while, maybe a month or two, then report my results here on my blog :-) However I will limit my intake to a maximum of 4000 UI per day during this initial period.

One aim is to see whether this supplementation will have any impact on my recent asthma but I am more interested to see if it will allow me to better tolerate certain food items which are outside my normal anti-RA diet. Will it prevent or reduce my symptoms? Will it improve one or two existing symptoms which I already have?

Here are the links to some of the most interesting articles along with a paper (pdf file) on the relationship between vitamin D and arthritis.

Could Vitamin D Really Cure Your Arthritis? – The Mail Online

Reasons That Vitamin D May Matter – The New York Times

Why You Need More Vitamin D – The Huffington Post

Relationships Among Vitamin D, Disease Activity, Pain and Disability in Rheumatoid Arthritis – Rheumatology Online

Vitamin D Deficiency in Rheumatoid Arthritis – PubMed

Vitamin D Intake Is Inversely Associated with Rheumatoid Arthritis (64Kb pdf file)

A Few Interesting Facts About Vitamin D

• Vitamin D is not actually a vitamin! This is because we can make it ourselves from ultraviolet light falling on our skin (more about this further down). A ‘vitamin’ is defined as something that we need to obtain from our diets i.e. something that we can’t make for ourselves. Of course in the real world, many people do not make enough vitamin D by the natural method so must obtain it from their diet, hence it is commonly called a vitamin.
• It is well known that exposing our skin to sunlight produces vitamin D, however there is more to this process. Vitamin D is actually formed by the UV-B in sunlight falling on the ‘oil’ on our skin – which sometime later is then absorbed complete with vitamin D, back into our skin.Unfortunately there are many barriers to this natural process in today’s world; people use sunblock, people wash frequently with soap so the skin’s natural oil is not available, the amount of sunshine in the UK for example is minimal in the first place (see the beginning of this post!). Other factors such as perfume & cologne, medication, skin colour, clothes, exercise and so on, can also affect vitamin D production and absorption.
• Vitamin D is not actually a vitamin (deja vu!), it is a precursor hormone (a steroid molecule) which after a bit of processing by the liver becomes active as 25-hydroxycholecalciferol or by the kidneys as 25-dihydroxycholecalciferol. Kidney disease for example, has been associated with vitamin D deficiency.
• Vitamin D is not actually a vitamin (deja deja vu!), it is a group of two molecules D2 & D3. D2 is the version of vitamin D produced by plants and D3 is the version produced by animals and humans. D2 is ‘ergocalciferol’ and D3 is ‘cholecalciferol’ hence vitamin D’s other name: ‘calciferol’. The D3 version is the one to use in your diet if you are supplementing, as it is more effective than D2. :-)
• Vitamin D is very important in helping with the absorption of calcium, it is also important in the facilitation of REM sleep and I’ve read a number of articles linking vitamin D deficiency to depression, vertigo, and memory problems for example.
• Artificial, commercial vitamin D such as Viosterol (D2) is produced by exposing ergosterol (a sterol found in fungus) to ultraviolet light. D2 is technically the only vitamin D supplement available to strict vegans and vegetarians since D3 is produced from animals (since I wrote this post, vegan D3 has become readily available), usually sheep’s wool! Yes, that’s right, they take all the lovely greasy oil (lanolin) from sheep’s wool and irradiate it with UV to produce vitamin D3 supplements. :-) So if you are vegan or strict vegetarian, you might want to check if any of your foods have been ‘fortified’ with animal-sourced vitamin D3. In my case, although I would like to be fully vegetarian, I’m afraid my health and my responsibilities are a higher priority.
• Natural sources (although I would definitely not recommend these) of vitamin D3 include; free-range egg yolks and milk but these don’t really contain enough to make much difference to our health (unless vitamin D2 or D3 has been added to milk for example). The most potent ‘natural’ dietary sources are fish-liver oil such as cod-liver oil, and oily fish such as salmon and tuna (but again I would definitely not recommend these).

“Baby gorilla sleeping” photo (modified with my captions) taken by bartdubelaar is licensed under CC BY-SA 2.0