The effect of ginger supplementation on serum C-reactive protein, lipid profile and glycaemia: a systematic review and meta-analysis

Abstract

AimTo undertake a systematic review and meta-analysis of prospective studies to determine the effect of ginger supplementation on serum C-reactive protein (CRP), lipid profile, and glycaemia.MethodPubMed-MEDLINE, Web of Science, Cochrane Database, and Google Scholar databases were searched (up until July 2016) to identify prospective studies evaluating the impact of ginger supplementation on serum CRP. Random-effects model meta-analysis was used for quantitative data synthesis. Sensitivity analysis was conducted using the leave-one-out method. Heterogeneity was quantitatively assessed using the I2 index. Systematic review registration: CRD42016035973.ResultsFrom a total of 265 entries identified via searches, 9 studies were included in the final selection. The meta-analysis indicated a significant reduction in serum CRP concentrations following ginger supplementation [weighted mean difference (WMD)−0.84 mg/L (95% CI −1.38 to −0.31, I2 56.3%)]. The WMD for fasting blood glucose and HbA1c was −1.35 mg/dl (95% CI −2.04 to −0.58, I2 12.1%) and −1.01 (95% CI −1.28 to −0.72, I2 9.4%), respectively. Moreover, high-density lipoprotein and triglyceride significantly improved after ginger administration [1.16 mg/dl (95% CI 0.52 to 1.08, I2 12.3%) and −1.63 mg/dl (95% CI −3.10 to −0.17, I2 8.1%), respectively]. These findings were robust in sensitivity analyses. Random-effects meta-regression revealed that changes in serum CRP levels were independent of the dosage of ginger supplementation (slope −0.20; 95% CI −0.95 to 0.55; p=0.60).ConclusionsThis meta-analysis suggests that ginger supplementation significantly reduces serum CRP and improves glycaemia indexes and lipid profile. Randomized control trials with larger sample size and with a longer-term follow-up period should be considered for future investigations.

Effect of Sodium‐Glucose Cotransport‐2 Inhibitors on Blood Pressure in People With Type 2 Diabetes Mellitus: A Systematic Review and Meta‐Analysis of 43 Randomized Control Trials With 22 528 Patients

“…Based on the recommendations of the Cochrane Handbook, the mean change from baseline in the levels of outcome variables of interest and standard deviations (SD) for both intervention and control groups were used to calculate the effect size 56. In brief, the net changes in measurements (change scores) were calculated as (measure at end of follow‐up)−(measure at baseline).…”

“…A random‐effects model (using the DerSimonian‐Laird method) and the generic inverse variance method were used to derive pooled estimates across studies 60. Heterogeneity was quantitatively assessed using the I 2 index,60 which measures the extent of true heterogeneity 61.…”

“…Heterogeneity was quantitatively assessed using the I 2 index,60 which measures the extent of true heterogeneity 61. It can be interpreted as the percentage of the total variability in a set of effect sizes due to true heterogeneity, that is, to between‐studies variability 61.…”

“…It can be interpreted as the percentage of the total variability in a set of effect sizes due to true heterogeneity, that is, to between‐studies variability 61. Low, moderate, and high I 2 values are 25%, 50%, and 75%, respectively 60. When heterogeneity is substantial, a prediction interval rather than a confidence interval can help to provide a better sense of the uncertainty around the effect estimate 61…”

The impact of vitamin D supplement intake on vascular endothelial function; a systematic review and meta-analysis of randomized controlled trials

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