Is there a link between vitamin D and MS?

Researchers in the multiple sclerosis (MS) field are interested in vitamin D because it has long been known that MS occurs more commonly in populations who live in countries far from the equator where they are exposed to lower levels of sunlight. This suggests, therefore, that there might be a link between vitamin D deficiency and the risk of developing MS.

Some recent research studies suggest that a lack of vitamin D in early childhood or even in utero (in the womb) may raise risk for developing MS later in adulthood. One study published recently in the journal JAMA Neurology, for example, found that babies born in London in May (i.e. the pregnancy was mainly during the northern hemisphere winter months) have significantly lower levels of vitamin D and a potentially greater risk for developing MS than babies born in November (after a primarily summer pregnancy). The mothers whose babies were born in May likely got more exposure to sunlight, and thus had higher vitamin D levels.

Can vitamin D intake relieve MS symptoms?
Medical scientists don’t yet know whether higher intakes of vitamin D can help manage MS in people who already have the disease. Some studies have suggested that it may indeed be helpful, but there’s no scientific consensus on this yet.

In the meantime, it’s a good idea to have a blood test to see if you do have a deficiency – your doctor can advise you on this. Adequate vitamin D is important for everyone’s general health: among other benefits, it helps stave off osteoporosis and heart disease, and plays a role in the correct functioning of the immune system.  

How much vitamin D is enough?
The most efficient way to get enough vitamin D is from exposure to sunlight a day (on bare skin outside), which is pretty easy in a sunny climate like Australia’s.

However, in cases where people are not very mobile and spend a great deal of time indoors, more conscious effort needs to be made to get a few minutes (around 15 minutes has been suggested) per day. Debate is heated at present among health experts as to how much is enough, and in sunny parts the debate is complicated by people needing to avoid excessive sun exposure and the consequent risk of skin cancer. 

Getting vitamin D from food is much less efficient, but good dietary sources include oily fish, and fortified cereals, eggs and margarine. (Oily fish is a nutritious food that’s valuable to include in your diet for its multiple other health benefits too.) 

Vitamin D can also be taken in supplement form. You should still aim to get most of your vitamin D from sunlight and your diet, but in some cases a supplement may be appropriate. Never take more than the dose recommended by your doctor, however (of vitamin D or any supplement). Also note that taking vitamin D supplements together with cod liver oil can result in an overly-high intake.