Abstract
AIM: This study aimed to investigate the effect of coffee or coffee extract on serum ALT and AST levels in patients with non-alcoholic fatty liver disease (NAFLD), by compiling data from randomized controlled trials up to November 2024. BACKGROUND: NAFLD represents the most prevalent hepatic disorder, characterized by the accumulation of lipids within hepatocytes in the absence of substantial alcohol consumption or viral infections. Effective management relies on lifestyle changes, such as diet and exercise. Recent studies have suggested that coffee consumption may offer liver-protective benefits, potentially helping to reduce serum levels of liver enzymes. METHODS: Two researchers conducted an independent search across PubMed, Web of Science, and Scopus, including clinical trials that assessed the effects of coffee or coffee extract on liver function tests (LFTs) in individuals diagnosed with NAFLD. Meta-analysis was carried out using STATA software. RESULTS: After screening titles, abstracts, and full texts, four studies comprising five placebo-treatment pairs were included in the meta-analysis. Coffee or coffee extract did not significantly affect serum ALT (p= 0.45) and AST (p= 0.54) levels. CONCLUSION: There is insufficient evidence to support the effectiveness of coffee or coffee extract on serum ALT and AST levels. Due to the limited number of studies, small sample sizes, and short follow-up durations, further randomized controlled trials with adequate sample sizes and more extended follow-up periods are recommended.