Vitamin D Supplementation Improves Quality of Life and Physical Performance in Osteoarthritis Patients

Nutrients. 2017 Jul 26;9(8):799. doi: 10.3390/nu9080799.


(1) Background: Lower levels of serum 25-hydroxyvitamin D (25(OH)D) are common in osteoarthritis (OA) patients. However, the effect of vitamin D supplementation on muscle strength and physical performance remains unclear. This study will investigate the effects of vitamin D₂ supplementation on muscle strength and physical performance in knee OA patients; (2) Methods: One hundred and seventy-five primary knee OA patients with low levels of serum 25(OH)D (<30 ng/mL) received 40,000 IU vitamin D₂ (ergocalciferol) per week for six months. Body composition, muscle strength, physical performance, serum 25(OH)D level, leptin, interlukin-6 (IL-6), parathyroid hormone (PTH), protein carbonyl, and metabolic profile were analyzed; (3) Results: Baseline mean serum 25(OH)D levels in knee OA patients was 20.73 ng/mL. Regarding baseline vitamin D status, 58.90% of patients had vitamin D insufficiency, and 41.10% had vitamin D deficiency. After vitamin D₂ supplementation for six months, mean serum 25(OH)D level was 32.14 ng/mL. For post-supplementation vitamin D status, 57.10% of patients had vitamin D sufficiency and 42.90% had vitamin D insufficiency. From baseline to six months, there was a significant increase in mean serum 25(OH)D level (p < 0.001), while mean LDL cholesterol (p = 0.001), protein carbonyl (p = 0.04), and PTH (p = 0.005) all significantly decreased. Patient quality of life (SF-12) and pain (visual analog scale, VAS) both improved significantly from baseline to the six-month time point (p = 0.005 and p = 0.002, respectively). Knee OA patients demonstrated significant improvement grip strength and physical performance measurements after vitamin D₂ supplementation (p < 0.05); (4) Conclusions: Vitamin D₂ supplementation for six months reduced oxidative protein damage, decreased pain (VAS), improved quality of life, and improved grip strength and physical performance in osteoarthritis patients.

Keywords: muscle strength; osteoarthritis; physical performance; vitamin D2 supplementation.

MeSH terms

  • Aged
  • Biomarkers / blood
  • Biomechanical Phenomena
  • Body Composition / drug effects
  • Dietary Supplements*
  • Ergocalciferols / therapeutic use*
  • Female
  • Hand Strength
  • Health Status
  • Humans
  • Knee Joint / diagnostic imaging
  • Knee Joint / drug effects*
  • Knee Joint / physiopathology
  • Male
  • Middle Aged
  • Muscle Strength / drug effects
  • Osteoarthritis, Knee / diagnosis
  • Osteoarthritis, Knee / drug therapy*
  • Osteoarthritis, Knee / physiopathology
  • Osteoarthritis, Knee / psychology
  • Oxidative Stress / drug effects
  • Pain Measurement
  • Protein Carbonylation / drug effects
  • Quality of Life*
  • Recovery of Function
  • Thailand
  • Time Factors
  • Treatment Outcome
  • Vitamin D / analogs & derivatives
  • Vitamin D / blood
  • Vitamin D Deficiency / blood
  • Vitamin D Deficiency / diagnosis
  • Vitamin D Deficiency / drug therapy*


  • Biomarkers
  • Ergocalciferols
  • Vitamin D
  • 25-hydroxyvitamin D