News Release

Sun exposure seems to reduce risk of multiple sclerosis

Past exposure to sun, skin phenotype, and risk of multiple sclerosis: case-control study BMJ Volume 327, pp 316-20

Peer-Reviewed Publication

BMJ

Higher sun exposure during childhood and early adolescence is associated with a reduced risk of multiple sclerosis, finds a study in this week's BMJ.

Multiple sclerosis is more common at higher latitudes, which generally have lower levels of ultraviolet radiation.

The study was carried out in Tasmania, which is located at high latitude and has a high prevalence of multiple sclerosis. Researchers surveyed 136 patients with multiple sclerosis and 272 controls about past sun exposure, measures to protect against the sun, use of vitamin D supplements, medical history, and other factors thought to be associated with multiple sclerosis. Skin damage and skin colour were also assessed.

They found that higher sun exposure when aged 6-15 years (average 2-3 hours or more a day in summer during weekends and holidays) and greater skin damage was associated with a decreased risk of multiple sclerosis.

Higher exposure in winter seemed more important than higher exposure in summer and the associations persisted after adjusting for fair skin and exposure after onset of disease, say the authors.

They suggest that insufficient ultraviolet radiation or vitamin D, or both, may influence the development of multiple sclerosis.

###


Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.