Vitamin D deficiency is unlikely to be “the single explanatory factor” for the very high rates of multiple sclerosis (MS) in Orkney and Shetland, according to the scientist who has led research into the subject.
Dr Jim Wilson was in Lerwick this week to discuss the initial results of the Northern Isles Vitamin D Study, which tested blood samples from 2,300 people in the islands.
Levels of vitamin D in these samples were measured alongside rates of certain diseases – among them MS, diabetes and heart disease – and this data was compared to 1,000 samples taken in the Central Belt of Scotland.
Given that its principle source is sunshine, Dr Wilson was surprised to find that while levels of vitamin D in the Northern Isles were “terribly low” – around 65 per cent of those sampled were either deficient, severely deficient or at high risk of deficiency – they were in fact marginally higher than those taken from samples in mainland Scotland.
The occupation of those providing samples would have some impact on the results. People with outdoor jobs – of which there are a higher proportion here than in a city – will inevitably get more contact with sunlight than those who work indoors. The results also vary dramatically through the course of a year, with only nine per cent of people found to be deficient in August, compared to 51 per cent in December.
Significantly, the study found no correlation between vitamin D levels in individuals and any of the diseases that were measured. Except, that is, for MS.
In the case of MS, the results were rather less conclusive. Individuals with the disease generally did have very low levels of the vitamin, but it was impossible to say whether this was a cause or a potential effect (the result of spending less time outside, say).
However, the fact that overall levels of vitamin D were not lower here than in the Central Belt suggests that, while it remains an “important” part of the story, and a “risk factor”, it does not provide the long-hoped-for explanation of why Shetland and Orkney have such high rates of multiple sclerosis.
The research into this subject is not at an end, however. Dr Wilson is working together with a newly-formed local group to instigate further study into the incidence of the disease in the islands. Fund-raising for this project is due to commence in earnest soon, with the money going to pay for a PhD student to continue with detailed and focused research on MS.
This will include further investigation into vitamin D deficiency, as well as other potential risk factors.
It will also tie closely into the research already underway in the Viking Health Study, for which Dr Wilson is also responsible.
Five hundred people have already volunteered to take part in that study, based in the former council offices at 4 Market Street, and 200 of those volunteers have been tested.
Over the next two years, a further 1,500 will be involved, making this a hugely significant project, that will provide research material into the health and genetics of Shetlanders.
To take part in the full study, volunteers are required to have two or more Shetland grandparents, and invitations are to be sent out this week to a further 500 people in that category. However, those with just one or no Shetland grandparents can also take part in the health research.
Anyone wishing to get involved in the Viking Health Study should contact Thelma on 0131 651 5141 or 0131 651 5575. To find out more about the Orkney and Shetland MS Research Project contact Tom or Alma Stove.