Higher consumption of ultra-processed foods and long-term risk of metabolic dysfunction-associated steatotic liver disease and primary liver cancer: A meta-analysis of preliminary evidence.

[BACKGROUND] Ultra-processed foods (UPFs) are a major component of the Western diet, and their consumption is increasing worldwide. Although there is compelling evidence for the effects of UPF on non-communicable diseases, data on their long-term effects on liver health are limited.

[METHODS] We systematically searched PubMed and Embase (from 2009 to September 5, 2025) for prospective cohort studies assessing the association between higher UPF consumption (defined by the NOVA 4 classification) and the risk of developing metabolic dysfunction-associated steatotic liver disease (MASLD) and primary liver cancer outcomes. Meta-analysis was performed using a random-effects model with the restricted maximum likelihood estimator and Knapp-Hartung adjustment to obtain pooled adjusted hazard ratios (HR) with 95 % confidence intervals (CIs).

[RESULTS] We included 7 studies with a total of 1,272,317 participants. The highest UPF consumption was significantly associated with an increased long-term risk of MASLD (pooled HR 1.32, 95 % CI 1.11 to 1.58). Moreover, the available evidence suggests no statistically significant association of higher UPF consumption and the long-term risk of developing primary liver cancer (pooled HR 1.21, 95 % CI 0.52 to 2.79), including hepatocellular carcinoma (pooled HR 0.98, 95 % CI 0.66 to 1.45) and intrahepatic cholangiocarcinoma (HR 1.00, 95 % CI 0.50 to 2.03). Sensitivity analyses did not modify these results. When UPF consumption was analyzed as a continuous variable, we found three cohort studies demonstrating its significant association with increased risk of MASLD and three cohort studies reporting conflicting results for primary liver cancer.

[CONCLUSIONS] These preliminary findings suggest that higher consumption of UPFs may contribute to an increased long-term risk of MASLD, highlighting the potential benefits of reducing UPF intake as part of preventive strategies.