Lack of sun could explain Scotland’s high MS rate

NEW RESEARCH could shed light on why sunshinedeprived Scotland has one of the highest rates of multiple sclerosis in the world.

Clear links on the effects of sunlight and vitamin D on immune system cells have been uncovered during research at Aberdeen University.

It is hoped the results of the studies will provide new insights into autoimmune diseases such as multiple sclerosis (MS).

The research – published in the Journal of Allergy and Clinical Immunology – shows how UV (ultraviolet)-B light boosts vitamin D, as well as cells in our body responsible for regulating or balancing the immune system.

Vitamin D is made in our bodies by UV-B light from the sun.

Dr Anthony Ormerod, clinical reader in dermatology at Aberdeen university, said: “We found UV-B light boosted the production of vitamin D and of regulatory T cells, which play an important role keeping our immune systems in check.”

“While too much exposure to sunlight is harmful and increases skin cancer risk, these results suggest subjects in our study would have some benefits from small amounts equivalent to summer exposure in the winter, but more work needs to determine the role of sunlight and the role of supplementing the diet with vitamin D.”

Previous research has shown regulatory T cell function is enhanced by vitamin D. Patients with autoimmune diseases have less regulatory T cells.

Autoimmune diseases such as MS and type 1 diabetes are caused by the immune system mistakenly attacking the body tissue or harmless substances that enter the body.

Researchers believe the link between vitamin D deficiency and MS might explain higher rates of autoimmune disease among people living further away from the equator, with lower levels of winter sun.

Patients living in the north of Scotland, which has the highest rate of MS in the UK, were tested with artificial UV-B light therapy during the research.

However Dr Helen Macdonald, senior lecturer in nutrition and translational musculoskeletal research at the university, warned: “We would also want to stress that we are not advocating sunbed use since this is not the same type of radiation produced by sunbeds.”