Study ties vitamin C to lower MS risk for some groups

Taking vitamin C supplements may reduce the risk of developing multiple sclerosis (MS), particularly for people with a higher genetic predisposition to the disease, according to a study.

The researchers stressed that further work is needed to validate the findings, but they said their data warrant additional studies to look at how vitamin C affects MS risk and how these effects are modulated by a person’s underlying genetic code.

The study, “Association of Vitamin C Supplementation and Genetic Susceptibility with Multiple Sclerosis Risk: A Prospective Population-Based Cohort Study,” was published in Nutrients.

MS is marked by inflammation that damages healthy tissue in the brain and spinal cord. The disease’s causes are not fully understood, but a variety of MS risk factors have been identified, ranging from viral infections to genetic variations.

Vitamin C, also known as ascorbic acid, is an essential nutrient that’s vital for many functions within the body. Among its effects, vitamin C is a powerful antioxidant and has been shown to have nerve-protective properties. Some studies have suggested that the risk of developing MS is lower in people with higher vitamin C intake, but others have found no association between vitamin C and MS risk.

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UK Biobank data

Researchers in Italy analyzed data from the U.K. Biobank, a long-term study tracking health outcomes among people in the U.K. recruited between 2006 and 2010. The team examined data from 486,908 adults without a neurological disease and compared vitamin C intake between those who eventually developed MS and those who didn’t.

Nearly one in 10 participants reported regularly taking vitamin C supplements when they entered the study. Over a median follow-up of more than a decade, 452 people developed MS.

Results showed that vitamin C supplementation was associated with a significant reduction in MS risk, by roughly 49%. The risk was reduced for both men and women, and for people younger than 60.

Because genetics is known to affect MS risk, the researchers also examined how genetic factors influenced the association between vitamin C and disease risk. Results showed that vitamin C supplements were significantly associated with a reduced risk of developing MS in people with high or average genetic risk scores.

But in people with low genetic risk scores, vitamin C supplementation showed no significant association with MS risk.

“In the large UK Biobank prospective cohort, regular vitamin C supplementation was associated with a lower risk of incident MS, particularly among individuals with average to high genetic susceptibility,” the researchers concluded.

The team said it’s unclear why vitamin C’s effect on MS risk might vary by genetics, highlighting a need for further research. They also stressed that their analysis could not account for all factors that may influence MS risk, so the associations reported in the study should be interpreted with caution.

Still, they said their findings “provide a rationale for further investigation in independent cohorts, functional studies, and, ultimately, randomized intervention trials to determine whether vitamin C supplementation has a causal role in MS prevention and whether this differs according to genetic susceptibility.”