MS patients who harbor low levels of vitamin D early in their disease fare worse over the next several years than patients with higher levels.
Multiple sclerosis is marked by damage to the fatty sheaths coating nerve fibers in the brain. The result can be an off-and-on series of symptoms including loss of muscle control, numbness and problems thinking. Vitamin D, which the body makes from sun exposure, has shown promise in fighting a variety of diseases and may limit this MS onslaught (SN: 7/16/11, p. 22).
In 2002, researchers studying the effect of the drug beta-interferon-1b against MS set aside blood samples from 465 patients. When researchers recently analyzed those samples, they found that patients who had blood levels of vitamin D exceeding 20 nanograms per milliliter at six and 12 months after the onset of MS had fewer symptom flare-ups during the rest of the five-year study than those with lower readings did. Some scientists think 20 nanograms per milliliter is a healthy level; others see 30 as a healthier minimum.
MRI scans revealed that, after five years, those who had started out with low vitamin D levels had four times as much myelin damage as those who had higher levels. The results appear in the March JAMA Neurology.
