Higher sun exposure in early life is linked to a decreased risk of multiple sclerosis later on.

It is not clear what causes multiple sclerosis, a debilitating disease of the nervous system. But it seems to be more common in countries at high latitude, where there are lower levels of ultraviolet radiation. Tasmania is a good example and this is where a new study of the relationship between sun exposure and multiple sclerosis took place.

Researchers studied a group of 136 patients with multiple sclerosis, comparing them with 272 people who did not have the disease. All were asked about sun exposure in earlier life, and skin damage and skin color were also assessed.

Higher sun exposure from six to 15 years (two to three hours a day or more in summer during weekends and holidays), along with higher levels of skin damage, were associated with a decreased risk of multiple sclerosis. Higher exposure in winter months seemed to be more protective than during the summer. The researchers wonder if insufficient ultraviolet light exposure, or lack of vitamin D (or both) plays a role in the development of multiple sclerosis.

Source

British Medical Journal 9th August 2003