In today's world,
non-nutritive sweeteners (NNSs) are recognized as substitutes for
sugar or other high-calorie
sweeteners, and their consumption is increasing dramatically. However, there is ongoing debate regarding the impact of NNSs on anthropometric indices. To fill this gap in knowledge, the current GRADE-assessed systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted to evaluate the effects of artificial- and stevia-based
sweeteners consumption on anthropometric indices and serum
leptin level which is known as an
appetite-regulating hormone. A comprehensive search was conducted on the Scopus, PubMed, and Embase databases up to November 2022 to identify randomized controlled trials (RCTs) investigating the effects of NNSs on anthropometric indices and serum
leptin levels. Data extraction from qualified studies was performed independently by two researchers. A random- or fixed-effects model was used to estimate weighted mean differences (WMDs) and 95% confidence intervals (CIs) for anthropometric indices such as
body weight (BW), body mass index (BMI), fat mass (FM), fat-free mass (FFM), waist circumference (WC) and serum
leptin level. Heterogeneity between studies was assessed using Cochran's Q test and quantified using the I2 statistic. From a pool of 3212 studies initially identified, 20 studies with a total sample size of 2158 subjects were included in the analysis. Results of the pooled analysis showed that NNSs consumption had a significant reducing effect on BW (WMD: -1.02, 95% CI: -1.57, -0.46 Kg), FM (WMD: -1.09, 95% CI: -1.90, -0.29), and FFM (WMD: -0.83, 95% CI: -1.42, -0.23), but did not have any significant effect on BMI (WMD: -0.16, 95% CI: -0.35, 0.02), WC (WMD: -1.03, 95% CI: -2.77, 0.72), or serum
leptin level (WMD: -2.17, 95% CI: -4.98, 0.65). The findings of this study indicate that the consumption of artificial- and stevia-based
sweeteners may lead to a reduction in
body weight, fat mass, and free fat mass.