Ultra-Processed Food Intake and Risk of Adverse Liver Outcomes: A Meta-Analysis

Abstract

This meta-analysis systematically evaluated the association between ultra-processed food (UPF) intake and adverse liver outcomes, addressing a critical evidence gap as prior observational studies lacked pooled quantitative synthesis. Researchers conducted a comprehensive search in PubMed, Cochrane Library, Embase, and Web of Science (up to October 17, 2024) using Medical Subject Headings (MeSH) terms and keywords. Statistical analyses in Stata 14.0 employed fixed-effects (P > 0.1, I² ≤ 50%) or random-effects models (I² > 50%), with publication bias assessed via funnel plots and Egger's test. The analysis included 17 studies (11 cohort, 3 case-control, 3 cross-sectional; n = 1,092,950 participants). UPF consumption significantly increased risks of adverse liver outcomes (OR = 1.58; 95% CI: 1.34–1.86; I² = 89.9%), specifically non-alcoholic fatty liver disease (NAFLD) (OR = 1.72; 95%CI: 1.36–2.17), liver fibrosis (OR = 1.31; 95%CI: 1.08–1.59), and liver cancer (OR = 1.35; 95%CI: 1.03–1.76). Subgroup analyses revealed regional variations, with Asian cohorts showing lower NAFLD risk (OR = 1.47 vs. American/European studies). High heterogeneity (I² = 89.9%) persisted across analyses. Findings confirm UPFs as independent risk factors for liver diseases, mediated through metabolic pathways like fat accumulation and inflammation. This synthesis strengthens evidence for dietary guidelines limiting UPFs to mitigate global liver disease burdens. The study's robust methodology and large sample size underscore the clinical and public health implications of reducing UPF consumption.