Little exposure to sunlight can raise multiple sclerosis risk infants
Children of mothers who have had little exposure to sunlight during the first three months of pregnancy may be at increased risk of developing multiple sclerosis (MS) in adulthood, according to an Australian study.
Low vitamin D levels were always associated with an increased risk of MS. Experts suspect that the lack of sun exposure, the main source of vitamin D-from the mother may affect the central nervous system or the immune system of the fetus and may predispose to develop MS in the future.
In the Australian study, researchers analyzed the birth records of 1,524 patients with MS born between 1920 and 1950 and found that most were born in the months of November and December.
This means their first quarter occurred during the winter months between April and June, a time when the mothers in the southern hemisphere might prefer being inside to avoid cold.
Conversely, there were many fewer patients with MS born in May and June, making its first quarter occurred during the start of warm weather between September and November.
“The risk of MS was about 30 percent greater in those born in November and December (…) compared to the months of May and June,” the researchers said in a statement.
The research, by Judith Staples and Lynette Lim, from the Australian National University in Canberra, and Professor Anne-Louise Ponsonby, the Murdoch Children’s Research Institute, was published in the British Medical Journal on Friday.
Vitamin D may be particularly important for the development of fetal central nervous system, the researchers wrote.
“Vitamin D supplements for the prevention of multiple escleroris may also be needed during the development of the uterus,” they said in the document.
Their findings were supported by previous studies conducted in the northern hemisphere, they found more cases of MS among people born in May, whose mothers probably had little exposure to sunlight during the first quarter, in the colder months from September to November.
MS, which is more prevalent in regions that are further away from Ecuador, can cause permanent disability, with symptoms such as numbness or weakness in one or more limbs, partial or total loss of vision, tremors and unsteady gait.