from Birth Month Seen Linked to Multiple Sclerosis Risk
People born in May in the northern hemisphere have a higher than average risk of developing multiple sclerosis, researchers said on Tuesday.
An analysis of data from studies of more than 42,000 people in Canada, Britain, Denmark and Sweden showed that May babies have a 13 percent increased chance of suffering from the illness later in life, but that having a November birthday decreased the average odds by 19 percent.
... The effect was similar in all the countries but most prominent in Scotland which has the highest rate of multiple sclerosis (MS) in the world, according to Ebers.
... MS occurs when immune system cells attack and destroy the myelin sheath that protects the nerve cells in the brain and spinal cord. The cause of the illness is unclear. Scientists believe it may be due to a combination of genetic, dietary and environmental factors.
The illness is rare in Africa and most common in people living in colder countries. Most people are diagnosed with the disorder between the ages of 20-50.