Reduced vitamin D levels may be associated with an increased risk of multiple sclerosis, according to a new research article.

Brent Richards of McGill University and his colleagues found that a genetic decrease in the natural-log-transformed vitamin D level by one standard deviation was associated with a 2-fold increased risk of multiple sclerosis.

Multiple sclerosis is a debilitating autoimmune disease that affects the nerves in the brain and spinal cord. There is no known cure for multiple sclerosis and it usually presents between the ages of 20 and 40 years.

Based on their findings, researchers concluded that "genetically lowered vitamin D levels are strongly associated with increased susceptibility to multiple sclerosis. Whether vitamin D sufficiency can delay, or prevent, multiple sclerosis onset merits further investigation in long-term randomized controlled trials."

For the study, researchers analyzed data from 14,498 people with multiple sclerosis and 24,091 healthy controls. The authors found that a genetic decrease in the natural-log-transformed vitamin D level by one standard deviation was associated with a 2-fold increased risk of multiple sclerosis.

"Ongoing randomized controlled trials are currently assessing vitamin D supplementation for the treatment and prevention of multiple sclerosis ... and may therefore provide needed insights into the role of vitamin D supplementation," the authors noted.

The findings were detailed in the journal PLOS Medicine.