Last Updated on 6th January 2023 by Caroline Haye
What does vitamin D do?
As I write this post I am sitting in my garden enjoying some unusually warm UK Spring sunshine. I am feeling very grateful for this on two counts. Firstly, the unseasonably good weather. And, secondly, the fact that I am able to enjoy it without worrying about my skin. And as I soak up the rays it strikes me that a sunny garden is the perfect setting for a blog post about vitamin D and vitiligo.
I recently visited my doctor on a general health matter which required various blood tests. The consultation came to a close and I was just leaving when she casually mentioned something, as an afterthought. She said that my levels of vitamin D were borderline low. So perhaps I should sit out in the sunshine for 20 minutes every day to try to increase them. (If you aren’t sure what the connection is between sun exposure and vitamin D I will explain in a moment.)
Sun exposure alone may not give you enough vitamin D
This is the sort of advice most people would welcome as a great excuse for lounging about in a deckchair. (And, since getting my vitiligo under control, I’m no exception.) But, the fact is that I have been taking a daily dose of vitamin D equivalent to at least three times the recommended daily dose for years. And I do already take every possible opportunity for sun exposure. So, on hearing this, my doctor concluded that, without the supplements and sunshine, I would most certainly be deficient. Of course, my medical records show that I had a long history of vitiligo. But, if my doctor was aware of any link between vitiligo and vitamin D deficiency she didn’t let on. So I decided that, once again, it was time for some more research into the subject myself.
The vitamin D – vitiligo connection
Over the past few years I have come across plenty of vitiligo literature linking vitiligo to vitamin D deficiency But I was not clear about which condition causes which (the “chicken and egg” question). As it turns out, it appears to be a bit of one and a lot of the other. On one side of the coin, having vitiligo usually causes sufferers to stay out of the sun. They do this for fear of burning or drawing attention to their white patches by tanning the rest of their skin. And this naturally results in reduced levels of vitamin D.
But more interestingly, on the other side of the coin, research shows that individuals who have vitiligo, psoriasis and various autoimmune conditions have subnormal levels of vitamin D to start with. So, it seems that having vitiligo almost certainly means you are low in vitamin D in the first place. And if you then also avoid sun exposure, as most vitiligo sufferers do, you are making a bad situation worse.
Before you get too depressed, every cloud has a silver lining. And every problem flags up a potential solution. In this case, once you are aware of a connection between vitamin D deficiency and vitiligo, an obvious solution is to take vitamin D supplements and also get more sun exposure. But do read on before dashing off to the nearest health food store, because it is not quite as straightforward as that. There is some homework to do first on the subject of this tricky vitamin.
Some vitamin D facts
Historically, the role of this vitamin has not been well understood. But over the past several years it has become a hot topic, with new vitamin D research papers appearing on a very regular basis leading to a much greater awareness in medical circles, and in the media, of its importance .
Believe it or not, scientists don’t always agree as to whether D is a vitamin or a hormone. The scientific arguments can seem baffling unless you are well versed in science – which I’m not. So, before going any further, here is an idiot’s guide to vitamin D (designed, by me, for people like me).
It seems that vitamin D is undeniably a vitamin, i.e. an organic substance present in natural foods that is essential to normal metabolism and, if depleted, may cause deficiency diseases. But it also acts like a hormone, i.e. “a substance formed in one organ but transported in the blood to another organ and capable of altering the functional activity of that target organ.”
Vitamin D2 versus D3
There are two types of vitamin D: D2, which is what doctors formerly prescribed for children with Rickets. The other is D3 (or “cholecalciferol”), which is what you find in most over-the-counter supplements. Of the two, vitamin D3 is now the vitamin D of choice for supplementation because of its superior therapeutic value. It is the same type of D that your body produces in your skin. And this is responsible for the pigmentation process after exposure to the UV light present in sunshine (and, of course, in UVB phototherapy). This is why my doctor recommended sun exposure when she realised my vitamin D levels were low.
We are heavily reliant on sunshine for the production vitamin D because only small amounts are available in the diet. It is worth knowing that D3 (the more therapeutic type) is only found in animal-based foods. (Oily fish, egg yolks and raw milk are good sources). Some people with vitiligo follow a vegetarian or vegan diet in their quest for better health. But, without supplementation, they may be even more prone to D deficiency as a result.
It has been my experience that mainstream doctors hardly ever mention the word “vitamin”. They rarely talk about nutritional supplementation at all. So the fact that vitamin D has made its way into their vocabulary just goes to highlight its superstar status. (In fact, vitamin D even has its own “fan club”: the Vitamin D Council. This is a California-based organisation which educates people about the importance of sun exposure and vitamin D. (Their blog is well worth a read.)
A lack of joined-up thinking among GPs
It seems to me there is still a real lack of joined-up thinking among GPs. The impression I get is that they are generally aware of the health risks of not having enough vitamin D. (Hence, my doctor mentioned it casually, as an afterthought). But they are not good at joining up the dots.
My doctor didn’t make the connection between my long history of vitiligo, CFS and fibromyalgia. Neither did she consider a possible link with my borderline-cancerous ovarian cyst – all proven indicators of vitamin D deficiency. I am not blaming my GP for this. She clearly does not have the time or resources to play the diagnostic detective. But it does serve as a reminder that our western health system has significant blind spots. And it reminds me that some intelligent, in-depth googling in the right places can be a sensible thing to do if you are determined to take responsibility for your own good health.
Having said all of that, vitamin D supplementation is definitely not without its pitfalls. For example, every time I have added separate D supplements to my nutritional regime in the past I have immediately suffered some very unpleasant side effects and, not surprisingly, given up on them again. (Happily, the vitamin D in the “Boost” capsules I took did not cause me any such problems.) But that is a whole new subject in itself. So I will leave you with that cliff-hanger and continue with that topic next time.
