Ultra-Processed Food Consumption and Cancer Risk: An Umbrella Review of Systematic Reviews and Meta-Analyses.

Evidence on the association between ultra-processed food (UPF) consumption and cancer risk is inconsistent, and systematic reviews (SRs) and meta-analyses (MAs) are fragmented across different cancer types and study populations. A comprehensive synthesis is needed to evaluate the robustness of the evidence. We therefore conducted an umbrella review (UR) of SRs and MAs to synthesize the available evidence on the association between UPF consumption and the risk of various cancers. PubMed, Embase, Web of Science, and Cochrane Library were systematically searched from inception to January 15, 2026. Seven MAs and one SR were included. The methodological quality of the included reviews was assessed using AMSTAR 2, and the certainty of evidence was evaluated using the GRADE framework. UPF consumption may be associated with increased risks of overall cancer, colorectal cancer, breast cancer, and gastric cancer. Subgroup analyses indicated that age, region, dietary assessment methods, and study design may contribute to differences in the observed associations. According to the GRADE assessment, two associations were rated as low certainty, while eight were rated as very low certainty. The AMSTAR 2 assessment showed that three reviews were of low methodological quality and four were of very low quality. Overall, this umbrella review suggests that UPF consumption may be associated with an increased risk of several cancers, although the overall certainty of the evidence remains low. Further high-quality prospective studies using standardized methods to assess UPF consumption are needed to strengthen the evidence base and inform public health recommendations.