Weight and sun exposure linked to onset of multiple sclerosis

People with multiple sclerosis who got less sun exposure and had higher body mass as young adults developed the disease sooner than those who spent more time in the sun and were a normal weight, a new study finds.

In a study of over 1,100 Danish people with MS — a nervous system condition that causes muscle weakness and pain — patients who were overweight at age 20 developed multiple sclerosis an average of 1.5 years sooner than patients of normal weight. And subjects who reported spending time in the sun every summer’s day during adolescence developed the disease 1.8 years later, on average, than patients who got less sun exposure, Danish researchers report online October 7 in Neurology.

The results echo earlier work that found a link between adolescent obesity and risk of MS. And sun exposure may increase patients’ levels of vitamin D, which has been shown to protect against the disease, the researchers say.