What is the influence of policosanol supplementation on liver enzymes? A systematic review and dose-response meta-analysis of randomized controlled trials

Objective: Policosanol is a mixture of long chain alcohols refined from sugar cane. Significant reductions in liver enzymes have been observed in some studies. However, the impact of policosanol on liver enzymes remained controversial. The current meta-analysis aims to evaluate the effect of policosanol supplementation on the levels of alanine transaminase (ALT) and aspartate transaminase (AST). Methods: The literature was systematically searched for studies published up to November 2023 in PubMed/Medline, Google Scholar, EMBASE, and Scopus. Randomized controlled trial (RCT) studies were included to evaluate the intervention effect of policosanol compared to placebo on ALT and AST. DerSimonian and Laird models were used to calculate effect sizes. Results: Twenty-three trials including 2535 participants were included in the study. The combination of effect sizes, regarding the random-effects model, demonstrated significant changes in ALT serum levels after intervention (WMD: -1.48 U/L; 95% CI: -2.33 to -0.64; P = 0.001), and AST (WMD: -1.10 U/L; 95% CI: -1.70 to -0.51; P < 0.001). Subgroup analysis of AST and ALT showed that this reduction effect was most often observed at the dose of 20 mg/d. The dose-response analysis represented a non-significant non-linear connection between the dosage and duration of policosanol intervention in ALT and AST serum reduction. Conclusion: Policosanol supplementation exerts a beneficial effect on liver enzymes as well as ALT and AST concentrations in adults. However, further long-term and well-designed RCTs with better quality are needed to further assess and confirm these results.