Table 2.
Complete list of human studies involving vitamin C and osteoarthritis used for analysis and commentary.
| Human studies | ||||
|---|---|---|---|---|
| Title of study | Study type | Patient population | Significant findings | Citation |
| Effect of antioxidants on knee cartilage and bone in healthy, middle-aged subjects: a cross-sectional study | Prospective cohort | 297 Australians, 99% of which were aged 40–69 years | Tibial bone plateau area was smaller, fewer bone marrow lesions when supplementing AA | Wang et al. 50 |
| The effects of vitamin C supplementation on incident and progressive knee osteoarthritis: a longitudinal study | Longitudinal study | 1023 males and females aged 40 + years | 11% less likely to develop OA when taking vitamin C supplement compared to control -No effect on pre-existing OA progression |
Peregoy and Wilder 40 |
| High plasma levels of vitamin C and E are associated with incident radiographic knee OA | Nested case-control | 3026 males and females aged 50–79 years or at high risk of knee OA | Taking higher amounts than the RDA of both vitamin C and E may be associated with more OA changes | Chaganti et al. 53 |
| Do antioxidant micronutrients protect against the development and progression of knee OA | Retrospective cohort | 640 males and females | High dietary intake of AA was associated with reduced structural progression of OA. No effect on incidence | McAlindon et al. 54 |
| Associations between dietary antioxidants intake and radiographic knee OA | Cross sectional study | 4685 subjects over 40 years & undergoing weight bearing bilateral AP radiography of knee | More radiological evidence of knee OA in those supplementing with vitamin C | Li et al. 55 |
| Synergistic chondroprotective effect of alpha-tocopherol, ascorbic acid, and Selenium . . . |
In vitro analysis | Human chondrosarcoma cell lines (SW1353) induced into an inflammatory state | Adding additional antioxidant augments vitamin C’s ability to slow progression of OA in an vitro analysis. | Graeser et al. 56 |
| Ascorbic acid provides protection for human chondrocytes against oxidative stress. |
In vitro analysis | Human C28/I2 chondrocyte cell line treated with H2O2 | AA reduced activity of pro-inflammatory markers, decreased apoptosis, and stimulated production of collagen and proteoglycan | Chang et al. 57 |
| Comparative effects of vitamin C on the effects of local anesthetics ropivacaine, bupivacaine, and lidocaine on human chondrocytes. | In vitro analysis | Human chondrocytes isolated and exposed to local anesthetics | Adding vitamin C to intra-articular injections of local anesthetic reduces the chondrotoxicity seen with using the anesthetic injection alone | Tian and Li 58 |
| Relationship of sociodemographic and anthropometric characteristics and nutrient and food intakes with osteoarthritis prevalence in elderly subjects with controlled dyslipidemia: a cross-sectional study | Cross-sectional study | 314 subjects aged ⩾ 65 years old who were diagnosed with dyslipidemia | Average vitamin C intake was positively correlated with risk of developing osteoarthritis | Jeong et al. 51 |
| Ascorbic acid attenuates Senescence of Human osteoarthritic osteoblasts | Control trial | Bone chips from sclerotic and non-sclerotic regions of subchondral bone of human OA joints | Bone fragments grown in AA showed a negative correlation with senescent cells and a decreased expression of ROS. Supplementation with AA was found to help expand subchondral bone osteoblast in-vitro | Burger et al. 59 |
| Dietary antioxidants, non-enzymatic antioxidant capacity and the risk of osteoarthritis in the Swedish National march Cohort | Prospective cohort study | 29,406 males and females ⩾ 40 years old were included | No association between vitamin C intake and risk of developing OA was noted | Veen et al. 60 |
| Associations Between Vitamins C and D Intake and Cartilage Composition and Knee Joint Morphology Over 4 Years: Data From the Osteoarthritis Initiative | Longitudinal Study | 1785 male and females ⩾ 45 years old with Kellgren/Lawrence knee grades 0–3 | The cross-sectional analysis found a beneficial effect of vitamin C on joint degeneration (having inverse associations with cartilage T2 values and WORMS scores), while the longitudinal results showed no significant associations. | Joseph et al. 52 |
AA, Ascorbic Acid; AP, Anteroposterior; OA, osteoarthritis; RDA, Recommended Dietary Allowance; ROS, reactive oxygen species; WORMS, Whole-organ magnetic resonance imaging score.