Ultra-Processed Foods and Health Outcomes in Children and Adults: An Updated Narrative Umbrella Review With a Focus on Dose–Response

Abstract

Ultra-processed foods (UPFs) now contribute a substantial share of total energy intake. A growing body of evidence has linked UPF consumption to adverse health outcomes, but existing umbrella reviews are mainly restricted to studies published before mid-2023 and have seldom rigorously examined the shape of dose–response relationships, evaluating both linearity and nonlinearity. The aim of this study was to synthesize updated meta-analytic evidence on associations between UPF consumption and major health outcomes in children and adults. A narrative umbrella review synthesized meta-analyses of studies published through December 9, 2025. Outcomes included obesity, type 2 diabetes (T2D), cardio-cerebrovascular diseases (CCVDs), nonalcoholic fatty liver disease (NAFLD), cognition, mental health (anxiety and depression), dental health, cancer, and all-cause mortality. For each outcome, a lead meta-analysis was selected by comprehensiveness, recency, and methodological quality (separately for children and adults when feasible). Methodological quality was assessed using a ROBIS (Risk of Bias Assessment Tool for Systematic Reviews)-adapted tool. Certainty of evidence was rated with GRADE (Grading of Recommendations, Assessment, Development and Evaluation). Twelve lead meta-analyses (mainly from observational studies) covering 13 outcomes were identified (4/13 in children). Across all but 1 outcome, higher (vs lower) UPF consumption was associated with increased risk (see graphical abstract). Dose–response evidence indicated a 10% higher risk per 10% increase in UPF intake for T2D, a curvilinear risk increase for CCVDs, and no significant association for NAFLD; for other outcomes, rigorous dose–response analyses were lacking. Certainty of evidence was high for 1 outcome, moderate for 6, and low for 6 other outcomes. This updated umbrella review confirmed harmful associations of UPFs with multiple health outcomes, and added insights on children’s health, cognition, dental health, CCVDs, and dose–response. Despite remaining methodological gaps (including observational-based and nonrigorous dose–response analyses), current evidence supports population-wide strategies to reduce UPF intake.

Systematic Review Registration: PROSPERO registration no. CRD420251230427.