Vitamin D

Among patients with knee osteoarthritis, higher intake with both vitamins D and C is associated with less cartilage degeneration, while supplementation with vitamin Dalone over 4 years is linked with significantly less progression of knee joint abnormalities.

“Various vitamin deficiencies have identified in subjects with OA, including decreased vitamin C and D serum levels,” Gabby B. Joseph, PhD, of the University of California, San Francisco, and colleagues wrote. “One study found that the odds of having hip OA was 1.9 times lower in subjects with recommended or higher vitamin C intake and another study reported that 24% of patients with advanced OA (and upcoming [total knee replacement]) were vitamin D deficient (<40 nmol/L).

Knee joint health

Thus, understanding the impact of vitamin deficiency on knee joint health, and the value of nutritional supplements to prevent or treat OA is of significant scientific and clinical interest.” To analyze the links between vitamin C and D supplementation and MRI measures of cartilage composition and joint structure, Joseph and colleagues studied data from the Osteoarthritis Initiative.

Joseph and colleagues included 1,785 participants from the initiative with radiographic Kellgren Lawrence; knee grades of 0 to 3 in the right knee. The researchers analyzed vitamin C and D intake; including dietary and supplemental, from baseline using answers in the Block Brief 2000 questionnaire. In addition, they evaluated MRI data using 3T cartilage T2 quantification and semiquantitative joint morphology gradings (WORMS); at baseline and 4 years.

To determine the links between baseline vitamin intake and baseline WORMS scores; and cartilage T2, the researchers used linear regression. Among patients with knee OA, higher intake with both vitamins C; and D associate with less cartilage degeneration, according to data.

But according to the researchers, higher vitamin C intake associated; with lower average cartilage T2, medial tibia T2 and medial tibia WORMS (coefficient standard range = –0.07 to –0.05). However, higher vitamin D intake associated with a lower cartilage WORMS; sum score and medial femur WORMS score (coefficient standard range = –0.24 to –0.09).

 300 IU of vitamin D

But regular intake of vitamin Dsupplements, in doses of 400 IU at least one every week; over a period of 4 years, associated with significantly less progression of cartilage, meniscus and bone marrow abnormalities (OR range = 0.4 to 0.56). “Overall, the cross-sectional results showed that some measures of vitamin C and D intake from food and supplements associated with less cartilage degeneration,” Joseph and colleagues wrote.

“While consistent vitamin C supplementation over 4 years did not have a significant association with changes in joint morphology, consistent use of at least 300 IU of vitamin D at least 4-6 days per week) over 4 years associated with less progression of knee joint abnormalities in the cartilage and bone marrow, and consistent use of at least 400 IU at least 1-3 days per week was beneficial for cartilage, bone as well as meniscus tissues.