Evaluation of Ginger (Zingiber Officinale Roscoe) on Energy Metabolism and Obesity: Systematic Review and Meta-Analysis

Ginger called Zingiber officinale (Z. officinale) belongs to Zingiberaceae family. In recent years, studies have shown that ginger may have effects on appetite, thermogenesis, and gastric motility. Due to these effects, the present study aimed to review of studies evaluating the effect of ginger on energy metabolism and obesity. The screening of the studies published was performed in 4 databases (PubMed-Web of Science-Lilacs-The Cochrane Library). Among the 1428 studies, only 20 studies had sufficient data to be included in the systematic review. Literature shows that ginger may have important effects on energy metabolism and obesity in animal models via decreased carbohydrate and lipids oxidation, increased nerve activity, changes in hormone (leptin, insulin) and enzymes (amylase, lipase). Some human studies also show positive effects; however, the results are conflicting because of difference in active ingredients, low dose, and short administration period (single dose, 24 hours). In meta-analysis of studies showed that ginger significantly decrease BMI (95% CI:1.33 -4.02 to 1.84, p = .003). In conclusion, the association of ginger with energy metabolism and obesity may have positive effects. However, before a clear recommendation can be made determination of the active ingredient and optimal duration and dose, as well as possible effects with long-term usage.