Does curcumin improve liver enzymes levels in NAFLD? A systematic review, meta-analysis and meta-regression.

Abstract

The aim of this meta-analysis is to investigate the sources of heterogeneity in randomized clinical trials (RCTs) examining the effects of curcumin supplementation on liver aminotransferases in subjects with non-alcoholic fatty liver disease (NAFLD). We conducted a systematic search of the PubMed, SCOPUS, and Web of Science databases for RCTs and identified 15 studies (n = 835 subjects). We used random-effects models with DerSimonian-Laird methods to analyze the serum levels of ALT and AST enzymes. Our results indicate that curcumin did not affect serum ALT, but it did reduce AST levels. Notably, both outcomes showed high heterogeneity (p < 0.01). Subgroup analysis revealed that adding piperine to curcumin did not benefit aminotransferase levels in NAFLD patients. Additionally, we found a negative correlation between the duration of the intervention and the relative (mg/kg/day) curcumin dose with the reduction in liver aminotransferases. In summary, the sources of heterogeneity identified in our study are likely attributed to the duration of the intervention and the relative dose of curcumin. Consequently, longer trials utilizing high doses of curcumin could diminish the positive impact of curcumin in reducing serum levels of aminotransferases in patients with NAFLD.