Low levels of vitamin D in Orkney may explain reason for higher rates of multiple sclerosis

University of EdinburghMay 18 2016

Holidays abroad may hold the key to tackling Scotland's vitamin D deficiency, research suggests.

People who take foreign breaks have higher levels of vitamin D in their blood, which has been linked to wide-ranging health benefits, a study has found.

Farmers also have higher levels of the vitamin -- which is produced in the skin after exposure to sunlight -- according to the findings. Researchers at the University of Edinburgh surveyed the vitamin D levels of around 2000 people in Orkney -- 1 in 10 of the population -- as part of the ORCADES study.

The team were interested to see whether widespread vitamin D deficiency in Orkney might explain why rates of multiple sclerosis are higher there than anywhere in the world.

They were surprised to find that average vitamin D levels are higher in Orkney than mainland Scotland.

The highest levels were seen in farmers and people over 60 years of age who take regular foreign holidays.

Vitamin D is known to be associated with good bone health. It has also been linked to wide-ranging health benefits including lower blood pressure, reduced heart disease risk and better chances of surviving cancer.

Deficiency in vitamin D has been strongly linked to diseases including multiple sclerosis.

Studies have yet to prove that vitamin D is responsible or whether it serves as a marker for how much sun exposure a person has had. Scotland has one of the world's highest rates of MS with Orkney being the worst affected.

Dr. Jim Wilson, who led the study at the University of Edinburgh's Usher Institute, said: "It was surprising to see that levels of vitamin D were not worse in Orkney, and if anything they were better than in Mainland Scotland. It would appear that poor vitamin D status, while common enough, cannot explain the excess of Multiple Sclerosis we see in Orkney."

Emily Weiss, a PhD student at the University of Edinburgh who was involved in the study, said: "It was interesting to find that the traditional occupation of farming was associated with higher levels of blood vitamin D in Orkney. This may be because farmers are outside and utilising even the smallest window of vitamin-D strength sunshine.

"We also found that farmers in our Orkney cohort tended to be older, suggesting that the traditional way of life is changing, leaving younger people potentially more exposed to MS risk factors such as vitamin D deficiency."