Effects of Propolis Consumption on Liver Enzymes and Obesity Indices in Adults: A Systematic Review and Dose-Response Meta-Analysis.

ABSTRACT

Background: Propolis, a natural resin produced by bees, has been studied for its potential effects on liver enzymes and obesity indices. However, a meta-analysis is necessary to comprehensively understand the impact of propolis on obesity and liver function. Objectives: This meta-analysis of randomized controlled trials (RCTs) sought to evaluate the effects of propolis consumption on liver enzymes and obesity indices in adults. Methods: A systematic literature search up to December 2023 was completed in PubMed/Medline, Scopus, and Web of Science, to identify eligible RCTs. Heterogeneity tests of the selected trials were performed using the I 2 statistic. Random-effects models were assessed on the basis of the heterogeneity tests, and pooled data were determined as weighted mean differences (WMDs) with a 95% confidence interval (CI). Results: A pooled analysis of 24 trials showed that propolis consumption led to a significant reduction in alanine aminotransferase (ALT) (WMD -2.58; 95% CI -4.64, -0.52; P = 0.01), aspartate aminotransferase (AST) (WMD -1.84; 95% CI -3.01, -0.67; P = 0.002), and alkaline phosphatase (ALP) (WMD -24.90; 95% CI -42.13, -7.67; P = 0.005) in comparison with the control group. However, there were no significant effects on gamma-glutamyl transferase (GGT), body weight, BMI (in kg/m2), fat mass, body fat percentage, fat-free mass, adiponectin, waist circumference, hip circumference, and waist-hip ratio in comparison with the control group. Conclusions: We discovered that consuming propolis can lead to a significant decrease in ALT, AST, and ALP levels, without causing significant changes in GGT, anthropometric indices, and adiponectin levels. However, future well-designed RCTs with large numbers of participants and extended durations, focusing on precise propolis dosage and ingredients, are necessary.