Relationship between 25-hydroxy vitamin D and knee osteoarthritis: a systematic review and meta-analysis of randomized controlled trials

Wang R, et al. · Frontiers in Medicine

Pooled improvements in WOMAC pain and function and reduced synovial-fluid/effusion measures, with authors reporting greater benefit above 2000 IU/day; structural (cartilage-volume) findings remain driven by secondary endpoints of individually null trials.

Population

Knee OA patients across 8 RCTs

Intervention

Vitamin D supplementation (various regimens)

Comparator

Placebo

Limitations

Pools trials whose primary structural endpoints were null; heterogeneity and reliance on secondary outcomes mean the pooled positives should be read cautiously.