The effects of ginger supplementation on markers of inflammatory and oxidative stress: A systematic review and meta-analysis of clinical trials

The present systematic review and meta-analysis was conducted to investigate the effects of ginger supplementation on markers of inflammatory and oxidative stress. PubMed, Embase, Scopus, and Web of Science were systematically searched to identify relevant clinical trials evaluating the effects of ginger on serum CRP (C-reactive protein), TNF-alpha (tumor necrosis factor-alpha), IL-6 (interleukin-6), PGE2 (prostaglandin E2), TAC (total antioxidant capacity), and MDA (malondialdehyde) from inception up to September 2019. Mean difference and 95% confidence intervals were pooled using a random-effects model. Potential publication bias was assessed using visual inspection of funnel plot and Egger's weighted regression tests. After excluding irrelevant records, 20 full-text articles that included 25 separate studies were included to the meta-analysis. Pooled results of this study indicated a statistically significant effect of ginger on serum CRP, TNF-alpha, IL-6, TAC, and MDA levels following ginger supplementation in compared to the controls. Also, the effects of ginger on serum PGE2 was marginally significant. Moreover, the high heterogeneity was disappeared in subgroup analysis performed by age, duration, dosage, and quality. This current analysis indicates that ginger supplementation has a significant effects on serum inflammatory and oxidative stress markers.