Multiple Sclerosis News TodayTaking High-Dose Vitamin D Daily Over the Long Term Helps Reduce MS Relapses

📊 Evidence Review

A network meta-analysis of 32 randomized controlled trials involving 2,254 patients with multiple sclerosis (MS) found that long-term vitamin D supplementation added to standard disease-modifying therapy was associated with reduced relapse risk and modest improvements in disability scores. Benefits were observed primarily when supplementation continued longer than one year, while shorter-duration treatment showed no significant effect.

Clinical Considerations

• Long-term vitamin D supplementation (>1 year) was associated with approximately a 20% reduction in relapse risk compared with placebo.
• High-dose, long-duration supplementation demonstrated the strongest benefit for relapse reduction and disability outcomes.
• Long-term supplementation was also associated with a 49% lower risk of active inflammatory lesions and reduced overall lesion burden.
• Vitamin D supplementation did not increase serious adverse events, including hospitalization, death, pregnancy complications, or kidney stones.
• Evidence certainty was rated moderate for long-term relapse and disability outcomes but very low when comparing specific dosing strategies.

Practice Applications

• Recognize vitamin D supplementation as an adjunctive strategy rather than a replacement for disease-modifying therapy.
• Monitor adherence to both prescribed MS therapies and recommended supplementation plans.
• Educate patients that potential benefits appear linked to long-term use, not short-term supplementation.
• Reinforce the importance of individualized treatment decisions based on provider recommendations and laboratory monitoring.
• Coordinate care discussions when patients inquire about nonpharmacologic approaches to reducing relapse risk.