Vitamin D May Slow Multiple Sclerosis: Study
But whether MS patients should take supplements is subject of debate
Also, even though vitamin D is sold over the counter, it doesn't necessarily mean it's safe to take a lot. "Like any medication, it may have negative effects of which we are not aware," Mowry added.
Vitamin D is also obtained from sunlight and through certain foods, such as fatty fish and fortified dairy products.
Mowry and Waubant are heading up a large clinical trial of vitamin D in MS patients. Similar trials are underway in Europe and Australia, Waubant noted.
"It is my belief that these trials will help answer the important question of whether it is safe and effective to recommend high-dose vitamin D supplementation to people with MS," Mowry said.
For the study, researchers measured vitamin D levels in 465 patients with signs of MS who took part in a trial designed to study interferon beta-1b treatment. For the next five years, patients underwent MRI scans so the researchers could track brain lesions associated with the disease.
During the first year of follow-up, increases of 50 nmol/L of vitamin D were associated with a 57 percent lower risk of developing new brain lesions, the study findings showed.
In addition, patients had a 57 percent lower risk of relapse, the researchers found. They also had a 25 percent lower yearly increase in T2 lesion size (these hallmarks of MS appear as bright spots on an MRI) and a 0.41 percent lower yearly loss in brain size over the course of the study.