Seyed Mohammad Mousavi - Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences

Background and Aim: The clinical studies regarding the effect of L-arginine in human anthropometry have not been fully consistent, therefore, we carried out an updated systematic review and meta-analysis in order to precisely evaluate and quantify the efficacy of arginine on weight, waist circumference, and BMI. Methods: We searched online databases including PubMed, SCOPUS, and Google Scholar for relevant articles up to September 2017. Eligible articles were reviewed by two independent investigators. Changes in the baseline for case and placebo were used for calculation of weighted mean difference (WMD) derived from the random-effects model. Statistical heterogeneity between studies was examined using Cochran’s Q-test and I2 index. Funnel plot and Egger’s tests were performed to assess the publication bias.Results: The meta-analysis of 8 RCTs (9 treatment arms) showed a significant reduction in WC following L-arginine supplementation (WMD: -2.97 cm; 95% CI: -4.75 to -1.18, P=0.001). However, L-arginine intervention had not elicited a significant effect on BMI (WMD: -0.51 kg/m2; 95% CI: -1.11 to .08, P= 0.09) and body weight (WMD: -0.57 kg; 95% CI: -1.77 to 0.61, P= 0.34). Subgroup analyses displayed that longer-term interventions (≥8 weeks) had a positive effect on body weight and using <8 g/day L-arginine with longer duration (≥8 weeks) could significantly decrease BMI.Conclusion: The current meta-analysis results suggested L-arginine supplementation could reduce waist circumference. However, we failed to find a significant effect on weight and body mass index.

L-arginine, Weight, Waist circumference, BMI, Meta-analysis