The effect of Nigella sativa (black seed) supplementation on body weight and body composition: A GRADE-assessed systematic review and dose-response meta-analysis of randomized controlled trials

Many studies have suggested that Nigella Sativa supplementation may exert a beneficial effect on anthropometric indices; however, the findings are inconclusive. Therefore, this study was conducted to obtain an updated finding in this regard. Systematic search was conducted in PubMed, Cochrane Library, Web of Science, Scopus, Embase databases, and Google Scholar, up to August 2022. N. sativa supplementation significantly reduced BW (WMD =-1.46 kg; 95 % CI:-2.53,-0.39) and BMI (WMD:-0.58 kg/m2, 95 % CI:-0.86,-0.29) compared to placebo group. However, no significant reductions were found in WC (WMD:-2.54 cm, 95 % CI:-6.27, 1.19), HC (WMD:-1.92 cm; 95 % CI:-4.38 to 0.54), and WHR (WMD =-0.03; 95 % CI:-0.07, 0.01). The current meta-analysis revealed that N. sativa supplementation in adults led to a significant decrease in body weight and BMI, but not WC, HC, and WHR. Thus, according to our findings, N. sativa supplementation can be recommended as an adjunctive intervention in obesity management.