Evaluation of the efficacy of ginger on obesity management: a randomized, double-blind, placebo controlled clinical trial
Background: Ginger (Zingiber officinale Roscoe) is a widely used spice and medicinal herb. Evidences from the in vitro or experimental studies support the use of ginger as a functional dietary agent for weight management but research in humans is limited. In this regard, the present study was aimed to investigate the effects of 12 weeks ginger supplementation on some obesity related features. Methods: 80 healthy obese women (aged 18-45 years) were randomly assigned to receive either ginger or placebo supplement as 2 tablets (each 1 g) per day before meals for 12 weeks. Subjects were tested for changes in body weight, waist and hip circumferences (WC and HC) and body composition at baseline and at weeks 4, 8, and 12. The subjects were also asked to maintain their usual dietary habits and activity levels, and use no other dietary supplements during study. Data were analyzed using SPSS software (version 21.0; SPSS, Chicago, IL). Differences between groups from baseline to week 4, 8 and 12 were analyzed using analysis of covariance (ANCOVA) with the baseline scores and energy intake differences employed as the covariates. Repeated measures analysis of variance was also performed to examine within group differences by time. P-value < 0•05 was considered as significant. Results: There were no significant differences between the two groups at baseline in any of the parameters tested. Ginger supplement resulted in a slight but statistically significant decrease in body weight, BMI, WC, HC, waist to hip ratio (WHR), percent total body fat and total fat mass over 12 weeks as compared to pretest, whereas in the placebo group there are only significant decrease in WC and WHR. Conclusion: the changes in all of these parameters were statistically significant in ginger group compared to placebo (p.