Low levels of sunlight coupled with glandular fever could increase the risk of developing multiple sclerosis (MS), say researchers.
There are many suspected risk factors for MS and the disease is known to be more common away from the equator. The study in Neurology, suggested that low levels of sunlight could affect how the body responds to infection.
The MS Society said the study, based on hospital admissions data in England, added weight to existing evidence. MS affects about 100,000 people in the UK and is more common in the north of England than in the south.