Yanna Lee

A new Yale co-authored study links higher vitamin D levels to possible neuroprotection for individuals suffering from multiple sclerosis.

The study, published last Saturday in the European Journal of Neurology, draws a connection between higher vitamin D levels in the blood and higher gray matter levels in the brain. For individuals with MS, low vitamin D levels are linked to relapses and lesions in the brain, wrote principal investigator Ellen Mowry, neurology professor at Johns Hopkins University, in a Saturday email to the News. The National Multiple Sclerosis Society, a funder of the research, is currently involved in many studies attempting to ascertain the exact relationship between vitamin D and the causes and symptoms of MS, according to the National MS Society website.

“Higher levels of vitamin D in the blood are associated with a lower amount of loss of brain tissue over the course of the study. If this association is true, vitamin D supplementation could be studied as a way to prevent damage to the actual brain tissue,” Mowry said.

MS occurs less frequently in regions closer to the equator, where the exposure to sunlight and to vitamin D is higher, Mowry said. She added that her study aims to further validate that connection between vitamin D levels and MS. However, according to Scott Zamvil, neurology professor at the University of California, San Francisco and co-author on the paper, it is unclear whether vitamin D’s connection to MS is a causal relationship or simply a correlation.

The research was conducted using data from a 2012 study for which Zamvil was the principle investigator. From the data set collected for that study, 65 individuals were eligible for Mowry’s research, Zamvil said. The MRI data for those individuals was analyzed to measure gray matter volume in the brain and brain atrophy — the loss of brain tissue over time.

“The MRI was used to identify an association between the levels of vitamin D and changes we know are happening in brains with MS,” said Emmanuelle Waubant, co-author of the study and neurology professor at the University of California, San Francisco.

The researchers looked at new lesions in the brain, which indicate relapses, and measures of atrophy in the brain. The strongest correlation was drawn between lower vitamin D levels and high levels of brain atrophy, Waubant said, though she added that this does not confirm causality, since there may be another factor that leads to both low vitamin D levels and high brain atrophy.

The study is one of many looking at the role of vitamin D in MS, and has implications for both the understanding of the causes of the disease and the value of vitamin D supplements in treating it, Waubant said. Vitamin D supplements are already used for MS patients with unusually low vitamin D levels, but there are currently trials ongoing to see how those supplements in different forms can be used to treat the disease overall, Waubant added.

Multiple sclerosis is two to three times more likely to occur in women than in men, according to the National MS Society.