Okay, this is a bit creepy, because not only did I grow up in Northern Alberta (that would perhaps be the low sunlight exposure, although I’m pretty sure it was sunnier there than it is in Vancouver) I also, in grade 10, came down with Mononucleosis. I remember because I got teased a long time for getting “the kissing disease”… why the heck is it called that anyway?

This is a post from a very interesting blog about all kinds of health stuff; please CLICK HERE to go to the original blog! It’s called “A Health Blog” and it’s pretty great.

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Low Sunlight Exposure Plus Common Virus May Raise Multiple Sclerosis Risk

Tuesday, April 19, 2011

New research suggests that people who are exposed to low levels of sunlight coupled with a history of having a common virus known as mononucleosis may be at greater odds of developing multiple sclerosis (MS) than those without the virus.

“Multiple sclerosis is more common at higher latitudes, farther away from the equator,” said study author George C. Ebers. “Since the disease has been linked to environmental factors such as low levels of sun exposure and a history of infectious mononucleosis, we wanted to see whether the two together would help explain the variance in the disease across the United Kingdom.”

Infectious mononucleosis is a disease caused by the Epstein-Barr virus, which is a Herpes virus that is extremely common but causes no symptoms in most people. However, when a person contracts the virus as a teenager or adult, it often leads to infectious mononucleosis. The body makes vitamin D when exposed to ultraviolet B (UVB) light.

For the study, researchers looked at all hospital admissions to National Health Service hospitals in England over seven years. Specifically, they identified 56,681 cases of multiple sclerosis and 14,621 cases of infectious mononucleosis. Scientists also looked at NASA data on ultraviolet intensity in England.

The study found that adding the effects of sunlight exposure and mononucleosis together explained 72 percent of the variance in the occurrence of multiple sclerosis across the United Kingdom. Sunlight exposure alone accounted for 61 percent of the variance.

“It’s possible that vitamin D deficiency may lead to an abnormal response to the Epstein-Barr virus,” Ebers said.

He noted that low sunlight exposure in the spring was most strongly associated with multiple sclerosis risk. “Lower levels of UVB in the spring season correspond with peak risk of multiple sclerosis by birth month. More research should be done on whether increasing UVB exposure or using vitamin D supplements and possible treatments or vaccines for the Epstein-Barr virus could lead to fewer cases of multiple sclerosis.”