Your guide to Vitamin D and MS

Vitamin D is a hot topic in the MS community. It plays an essential role in our immune system and research is ongoing into how it might link to MS.

In this article our MS expert Dr. Schumacher explains all about vitamin D and how to work out if you might need to supplement it.

An introduction to vitamin D

What is vitamin D?

Vitamin D and its health benefits has been a hot topic in the last decade. It is a chemical messenger essential for multiple important body functions.

The body needs vitamin D for many different functions, among these are:

  • Bone growth
  • Neuromuscular function
  • Immune system.

Where does vitamin D come from?

Our body can produce around 90% of its vitamin D needs on it’s own. The rest we get from eating foods which contain vitamin D.

Food that are high in vitamin D include:

  • Fatty fish e.g. salmon, mackerel
  • Fortified dairy products
  • Egg yolks
  • Some mushrooms

Exposure to sunlight is essential for our bodies to produce vitamin D. When we’re exposed to UV-B rays an important chemical reaction happens in our skin which takes a precursor molecule and transforms it to vitamin D. After that our liver then converts it to an active form which our bodies can use.

Living in a cloudy climate

So, it all seems like a neat process. That is unless you live in a cloudy climate. One of the causes of vitamin D deficiency is lack of sunlight. It is assumed that in places above 40°N, which includes e.g. large parts of North America and most parts of Central Europe, sunlight might not be sufficient in the winter months to guarantee enough vitamin D production. This is why some people have to supplement vitamin D.

When might I need to supplement Vitamin D?

A range of medical conditions have been connected to low levels of vitamin D. Among these are osteoporosis, heart disease, diabetes, cancer, but also multiple sclerosis.

Low vitamin D levels have been linked with an increased risk of getting MS, but potentially also with more frequent relapses and increased disability in those with established MS.

So if I have MS I should supplement vitamin D?

So it seems quite reasonable to just supplement it, but as is often the case with MS, the answer is not a simple ‘yes’.

Firstly you should check if you have low levels of vitamin D. This is done by a doctor with a blood test.

If it is then confirmed that your vitamin D levels are below a threshold, the advice is clear: you should supplement vitamin D after a consultation with your doctor..

If you can, it is good to have your vitamin D levels tested from time to time, especially during the winter months.

Are there benefits to supplementing vitamin D if my levels are normal?

If your levels are normal, it is not necessarily recommended to take more vitamin D.

Although it is discussed a lot within the MS community, the evidence for additional benefits regarding relapse rates and disability progression is not clear yet.

In the past, there have been inconclusive studies done, and there are other larger studies ongoing about this topic. Until we have conclusive evidence, no expert can give clear advice on whether all MS patients should supplement vitamin D.

On the other hand, if you are already taking vitamin D supplements, this is unlikely to be a problem. You just need to be aware about risks of overdosing, see below.

Like with everything, the ‘right’ level will depend on where you live, so consult with your doctor to understand what it means for you. Be aware that there are different lab values described as being the threshold for low vitamin D if you search online. But do not worry, your doctor will have an understanding of the values that their lab uses.

How to supplement vitamin D if you need to

If you happen to have insufficient vitamin D and need to supplement it, there are different ways that you can do it:.

  1. Adapt your general diet.

This is actually not that easy because only a few foods contain higher levels of the compounds needed to make vitamin D. This puts you at risk of developing an unbalanced diet.

2.  Take vitamin D supplements  

These come as tablets, capsules or drops. Their dose of these products can be measured in both micrograms (µg or mcg) and International Units (IU).

How to choose the right supplement

As there are so many products out there it can be hard to choose the right one.

  • Look for supplements labelled as vitamin D3, rather than vitamin D2.
  • If you are comparing products, use International Units (IU) as it is the most standardised
  • A typical dose for someone with MS and low vitamin D levels is 1000 - 2000 IU per day
  • The maximum dose advised by the European Food Safety Authority (EFSA) is 4000 IU per day
  • Discuss it with your doctor and get your levels tested

Are there any risks associated with taking Vitamin D?

Vitamin D is a safe compound to take without having to fear side-effects and it is well tolerated by almost all people.

However, there is a rare risk of overdosing which can have serious side-effects. These mostly have to do with calcium overload (hypercalcaemia), as one important function of vitamin D is to increase calcium uptake in the bowel.

If you are taking very high levels of vitamin D to supplement, doctors may advise you to follow a low calcium diet as well. Generally, this involves eating less dairy products in order to prevent calcium building up in the body. Vitamin D toxicity and hypercalcaemia can damage the kidney if left untreated.

If you are taking higher levels of vitamin D (over 2000 IU per day) you need to make sure you’re having your vitamin and calcium levels checked every 3 months or so.

How about the ultra-high dose therapy (Coimbra protocol) with Vitamin D, should I take it?

Dr. Coimbra from Brazil has been working intensively on the effects of an ultrahigh-dose therapy with vitamin D on patients suffering autoimmune diseases, among them MS patients.

There are many non-scientific books and blogs referring to this therapy as a highly effective, game changing treatment for MS.

When considering the scientific evidence for this kind of therapy, there is so far not much evidence published which underlines the promised effectiveness.

On the other hand, there are risks attached to a high-dose substitution (see above). Therefore, experts recommend to be careful with the Coimbra protocol and definitely advise you to frequently consult your doctor and test your vitamin D and calcium levels if you have decided to start this therapy protocol.  

Still got questions?

Ask our MS expert, Dr. Adrian-Minh Schumacher.

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If you do need to supplement vitamin D, Emilyn can help you take it effectively. Set up a medication reminder now, and don’t forget to log any changes you see in your check in notes.

This article provides general information and discussions about health and related subjects. The information and other content provided in this blog, website or in any linked materials are not intended and should not be considered or used as a substitute for medical advice, diagnosis or treatment.