Effects of ginger supplementation on biomarkers of oxidative stress: A systematic review and meta-analysis of randomized controlled trials

Background: The present systematic review and meta-analysis were conducted to investigate the effects of ginger on biomarkers of oxidative stress such as glutathione peroxidase (GPx), malondialdehyde (MDA), and total antioxidant capacity (TAC) this meta-analysis was performed.

Methods: Five databases were searched from inception to May 2020 using relevant keywords. Results were reported as bias-corrected standardized mean difference (Hedges' g) with 95 % confidence intervals (CI) using random-effects models.

Results: Eleven RCTs were included. Ginger resulted in significantly increased on GPx (Hedges' g: 1.93, 95 % CI: 0.20 to 3.66, P = 0.029) and significant reduction in MDA (Hedges' g: -1.45, 95 % CI: -2.31 to -0.59, P = 0.001), but no significant change in TAC (Hedges' g: 0.42, 95 % CI: -0.03 to 0.88, P = 0.069). Greater reduction in MDA was detected in trials using ≤1 g ginger, lasted <12 weeks, participants aged ≥30 years old, among both gender and were conducted sample size ≤40. TAC was increased by administered high doses of ginger, lasted ≥12 weeks, mean age ≥30, sample size >40, and both gender and female.

Conclusion: Overall, this meta-analysis demonstrated ginger supplementation decreased MDA and increased GPx but the results showed no significant alterations in TAC activities.