Beyond the Pale

More sun exposure, higher vitamin D levels may decrease multiple sclerosis risk

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) Spending time in the sun can increase the amount of vitamin D you get. Vitamin D has been shown to strengthen your bones and immune system in addition to lowering the risk of certain diseases. Now it appears that sunlight and vitamin D may reduce the risk of multiple sclerosis (MS).

Researchers found that individuals who spend more time in the sun and have higher levels of vitamin D may have a lower risk of developing multiple sclerosis. While this study expands on research that found similar results, it is the first analysis to look at people who have the first symptoms of multiple sclerosis but had not been diagnosed yet. (Diagnosis of MS is tricky and usually depends on two or more "episodes" of neurological complications lasting for days or weeks.)

"Sun-bathing might lower your risk of MS."

According to Robyn Lucas, Ph.D., of Australian National University, sun exposure and vitamin D levels had independent effects on a person's risk of MS. Lucas adds that future research should assess sunlight and vitamin D in the prevention of MS.

In Depth

The study followed 216 people aged 18 to 59 who had experienced a first possible episode of multiple sclerosis and 395 people with no symptoms of possible MS. Participants in both groups were matched as closely as possible according to sex, age and regional location.

Researchers looked at skin damage the participants displayed from sun exposure, the amount of melanin in their skin and vitamin D levels (resulting from sun exposure, diet and supplement use) in the blood.

The researchers found that the risk of a diagnosed first-episode fell by 30 percent for each UV increase of 1,000 kilojoules and that people with the most skin damage from sun exposure were 60 percent less likely to develop a first event compared to those with the least damage. Individuals with the highest levels of vitamin D also were less likely to have a diagnosed first event than people with the lowest levels.

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Review Date: 
February 8, 2011
Last Updated:
April 12, 2011