The effect of 12-week garlic supplementation on symptom relief in overweight or obese women with knee osteoarthritis

Aims: Chronic joint pain and stiffness, and functional disability, are the major debilitating features of osteoarthritis (OA). The aim of this study was to assess the effect of 12-week supplementation with a garlic supplement on knee osteoarthritis outcomes in overweight or obese women. Methods: Seventy-six postmenopausal overweight or obese women (25 <= BMI <= 40kg/m(2)) with medically diagnosed knee OA participated in this randomised double-blind, placebo-controlled, parallel-design trial. After randomisation into 2 groups, patients received a daily dose of either 1000mg odourless garlic tablet, or placebo, for 12weeks. The total Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), as well as pain, stiffness and physical function subscales, were evaluated pre- and poststudy. Anthropometric parameters and body composition (using bioelectrical impedance analysis) were also assessed. Results: Following 12-week supplementation in overweight or obese women with OA, stiffness (but not pain, function or WOMAC total score) was significantly lower in the garlic group compared with the placebo group (1.4 +/- 1.6 vs 2.5 +/- 1.9, P=.023). The changes in WOMAC parameters showed no statistically significant differences between the 2 groups. WOMAC total score (38.4 +/- 15.9-30.6 +/- 15.7, P=.004) and all the subscales, including pain (8.3 +/- 3.7-7 +/- 4.4, P=.026), stiffness (2.3 +/- 1.6-1.4 +/- 1.6, P=.013) and physical function (27.7 +/- 11.9-22.2 +/- 12.4, P=.001) improved significantly in the garlic group post-intervention compared with pre-intervention; although pain subscale also decreased in the placebo group (9.6 +/- 3.1-6.9 +/- 3.7, P<.001). Conclusions: Although pre- to postintervention knee OA symptoms were improved in overweight or obese women receiving 12weeks garlic supplement, there was no significant difference in WOMAC changes compared with the placebo group. Further clinical trials are required to investigate the therapeutic value of garlic ingredients, and the potential role of placebo effect, in the management of OA symptoms.