In April 2019 researchers from Iran published their review of the medical scientific literature to assess the effect of L-arginine supplementation on body weight, BMI and waist circumference. A total of 8 studies were included in the review. Results showed that L-arginine supplementation appeared to significantly reduce waist circumference but had no significant effect on body weight and BMI. However, a further analysis revealed a reduction in body weight when the supplementation was taken for more than 8 weeks and a reduction in BMI when dosage was up to 8 g/day as well as the supplementation being taken for more than 8 weeks.
Mousavi SM et al. The Effect of L-Arginine Supplementation on Obesity-Related Indices: A Systematic Review and Meta-Analysis of Randomized Clinical Trials. Int J Vitam Nutr Res. 2019 Apr 15:1-11