The effects of Garcinia cambogia on glycaemic control and liver enzymes in adults: a systematic review and meta-analysis of randomised controlled trials

Previous studies have assessed how supplementing with Garcinia cambogia affects glycaemic control and liver enzyme levels; nevertheless, the results were not consistent. The study aimed to evaluate the impact of Garcinia cambogia on glycaemic control and liver enzymes through a systematic review and meta-analysis. Searches were conducted from the beginning through February 2023, using online databases (Scopus, Web of Science, PubMed, and Cochrane Library). Trials examining the impact of Garcinia cambogia on serum levels of fasting blood sugar (FBS), serum level of insulin, alanine transaminase (ALT), and aspartate transaminase (AST) in adults were included. The overall estimates and their 95% confidence intervals (CIs) were calculated using a random-effects model. This meta-analysis includes nine publications with 444 participants. The results showed that Garcinia cambogia has no significant effect on FBS (weighted mean difference (WMD): 1.02 mg/dl, 95% CI: −1.29, 3.33), insulin (WMD: −0.12 mU/L, 95% CI: −1.50, 1.25), AST (Hedges’ g: −0.08, 95% CI: −0.43, 0.26), and ALT (Hedges’ g: 0.27, 95% CI: −0.20, 0.73). Subgroup analysis showed that Garcinia cambogia significantly increased insulin levels in females and also increased insulin and FBS levels in those with a BMI ≥30 kg/m2. Nevertheless, the administration of Garcinia cambogia for more than 8 weeks significantly decreased insulin levels. This meta-analysis showed that supplementation with Garcinia cambogia has no significant effect on FBS, insulin, ALT, or AST levels compared with control groups; however, it seems that increasing the duration of the intervention may have a decreasing effect on insulin levels.