Osteoarthritis (OA) is one of the commonest forms of musculoskeletal disorders that leads to joint degeneration and has a major impact on patients' quality of life. Experimental and in vitro studies have suggested the protective roles of pomegranate juice (PJ) as a rich antioxidant source for mitigating cartilage inflammation.

Iranian scientists published on the Journal of the Science of Food and Agriculture an interventional study where 38 patients with knee OA were randomly divided into two groups: PJ or control for 6 weeks to evaluate the effect of this intervention on clinical signs, inflammation and antioxidant status.

Significant decreases in Western Ontario and McMaster Universities Osteoarthritis index (WOMAC) total score (P = 0.01), stiffness score (P = 0.00) and physical function score (P = 0.01) were observed in PJ group after the intervention. The means of serum levels of matrix metalloproteinase (MMP)-13 was significantly decreased (P = 0.02) and glutathione peroxidase was increased in the intervention group compared with the control group after the study period (P = 0.02).

According to the findings of this clinical trial, pomegranate juice consumption can improve physical function and stiffness, decrease breakdown cartilage enzymes and increase antioxidant status in patients with knee osteoarthritis.