Sun Exposure Linked to MS Risk
Sun Exposure During Childhood May Help Protect Against Multiple Sclerosis in Adulthood
WebMD News Archive
July 23, 2007 - Spending time in the sun as a child may help protect against
multiple sclerosis (MS).
In a new study of identical twins with only one twin having MS, the twin who
spent more time in the sun as a child had a lower risk of developing multiple
sclerosis than the twin who spent less time in the sun.
Researchers say they aren’t exactly sure why there may be a connection
between the sun’s rays and MS. But they say sun exposure may offer protection
by boosting the body’s immune system or indirectly reduce the risk by
stimulating vitamin D production. Previous studies have shown that vitamin D
may lower the risk of MS.
Multiple sclerosis is an autoimmune disease in which the body’s immune
system turns against itself and begins attacking healthy tissue, causing
symptoms such as muscle weakness and coordination problems. MS is typically
diagnosed in early to middle adulthood.
Sun May Protect Against MS
In the study, published in Neurology, researchers surveyed 79 pairs
of identical twins in which one twin had MS.
The twins answered questions about whether they or their twin spent more
time outdoors during hot days, cold days, and who spent more time sun tanning,
going to the beach, or playing team sports as a child.
Overall, the study showed that the twin with MS reported less sun exposure
as a child than the healthy twin.
“Our findings note the importance of sun exposure among people with
identical genetic risk for MS,” says researcher Thomas Mack, MD, MPH, of the
Keck School of Medicine of the University of Southern California in Los
Angeles, in a news release. “High priority should be given to research into how
sun exposure reduces MS risk if we are to unravel the mystery of what causes