Sunlight and vitamin D findings may help understanding of autoimmune diseases

By Jennifer Phillips

(Medical Xpress) -- Aberdeen scientists have demonstrated for the first time a clear link between sunlight, vitamin D and an impact on regulatory cells in the immune system in findings that might provide new insights into diseases such as multiple sclerosis (MS).

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

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

Some studies have suggested a link between vitamin D deficiency and autoimmune diseases such as MS. This possible link might also explain the increasing prevalence of autoimmune among those living far from the equator, where there are lower levels of winter sun.

Autoimmune diseases - like MS and type 1 diabetes - are diseases where the immune system mistakenly attacks the body’s own tissues or harmless substances that enter the body.

University of Aberdeen researchers studied patients in the north of Scotland - which has the highest rate of MS in the UK - who were being treated during winter with artificial UV-B light therapy for skin diseases caused by their immune systems acting inappropriately.

Researchers looked at the impact of the UV-B light on vitamin D levels, as well as its impact on cells known as regulatory T cells, which play a critical role in the immune system, keeping it in balance and preventing it from carrying out damaging autoimmune responses.

Regulatory T cells are known to be lacking in some patients with . Previous research has also shown that regulatory T cell function is enhanced by vitamin D.

Dr. Anthony Ormerod, Clinical Reader in Dermatology at the University, said: “Our study shows that UV-B light, which mimics sunshine, can have a striking effect on the of patients.

“We found that 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.

“Our findings have important implications for future interventions including the recommendations for healthy lifestyle and a possible role for phototherapy and / or vitamin D supplementation in the prevention or treatment of autoimmune and inflammatory diseases.

“While too much exposure to sunlight is harmful and increases skin cancer risk, these results suggest that 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.”

Dr. Helen Macdonald, senior lecturer in nutrition and translational musculoskeletal research and Chair of the National Osteoporosis Society Nutrition and Lifestyle forum, said: “There are risks associated with high levels of both therapies, so it is important that we get the balance right.

“We would also want to stress that we are not advocating sun bed use since this is not the same type of radiation produced by sun beds which already have well-documented health risks.

“The average dose of UV light that the volunteers received was the equivalent to sunlight exposure in Aberdeen over spring and summer and further work is required to determine if lower doses are effective.”

Professor Mark Vickers, Chair in Applied Medicine at the University, said: “Ours is the first study to demonstrate in patients a cause and effect between UV light, vitamin D and systemic immune function in people.”

Professor Rob Barker, Chair in Medicine and Therapeutics, added: “Our study suggests a predisposition to autoimmune and allergic responses may be explained by a deficiency in exposure to , which in turn leads to a lack of and regulatory T cells.”

Related Stories

How sunlight may reduce the severity of multiple sclerosis

Mar 03, 2011

New research into the neurodegenerative disease, Multiple Sclerosis (MS) offers new insight into the link between sunlight, vitamin D3, and MS risk and severity. The research, published in the European Journal of Immunology, studie ...

Study explores link between sunlight, multiple sclerosis

Mar 22, 2010

For more than 30 years, scientists have known that multiple sclerosis (MS) is much more common in higher latitudes than in the tropics. Because sunlight is more abundant near the equator, many researchers have wondered if ...

When too much sun is not enough

May 07, 2012

(Medical Xpress) -- Lupus patients show more severe symptoms of the disease if their vitamin D levels are low, an Australian-first study has found.

Recommended for you

Could trophoblasts be the immune cells of pregnancy?

Dec 18, 2014

Trophoblasts, cells that form an outer layer around a fertilized egg and develop into the major part of the placenta, have now been shown to respond to inflammatory danger signals, researchers from Norwegian University of ...

Moms of food-allergic kids need dietician's support

Dec 18, 2014

Discovering your child has a severe food allergy can be a terrible shock. Even more stressful can be determining what foods your child can and cannot eat, and constructing a new diet which might eliminate entire categories ...

Multiple allergic reactions traced to single protein

Dec 17, 2014

Johns Hopkins and University of Alberta researchers have identified a single protein as the root of painful and dangerous allergic reactions to a range of medications and other substances. If a new drug can ...

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.