Related Experiment Video
Updated: Jan 17, 2026
Evaluation of Colorectal Cancer Risk and Prevalence by Stool DNA Integrity Detection
Published on: June 8, 2020
Ultra-Processed Food Consumption and Colorectal Cancer Risk: a Systematic Review and 2-Stage Mediation Meta-Analysis
Sai Sharanya Akkapelli1, Veda Sheersh Boorla2, Mounica Majooju1
1Department of General Medicine, Prathima Institute of Medical Sciences, Karimnagar, Telangana, 505417, India.
Context:
The global increase in the intake of ultra-processed food (UPF) parallels rising rates of early-onset colorectal cancer (CRC), raising concern about possible causal links. Although observational studies suggest that UPFs contribute to gastrointestinal inflammation, it remains unclear whether CRC risk is mediated through inflammatory pathways such as inflammatory bowel disease (IBD).
Objective:
In this review we sought to evaluate, using a 2-stage mediation meta-analysis, the association between UPF consumption and CRC risk and to examine whether IBD mediates this relationship.
Data Sources:
We searched PubMed, Embase, Scopus, and Web of Science through September 2025.
Data Extraction:
Two reviewers independently extracted data using a standardized form, including study characteristics, UPF assessment method, exposure categories, follow-up, covariates, and adjusted effect estimates (hazard ratio [HR], relative risk [RR], odds ratio [OR], standardized incidence ratios [SIRs]). For UPF-CRC and UPF-IBD, the primary contrast was highest vs lowest UPF category, with per-10% increments recorded when reported. For IBD-CRC, adjusted RRs were abstracted similarly. No individual-level data were obtained.
Data Analysis:
Study-specific effect estimates were log transformed and pooled using random-effects models (REMLs). Heterogeneity was assessed via I2 and Cochran's Q. Associations of UPF-IBD and IBD-CRC were meta-analyzed separately and combined to estimate the indirect UPF-CRC effect via a 2-stage product-of-coefficients method, with SEs derived using the delta method.
Conclusions:
Sixteen cohort studies including over 2 million participants met inclusion criteria. High UPF intake was modestly associated with increased CRC risk (RR 1.13, 95% CI, 1.06-1.20) and incident IBD (RR 1.33, 95% CI, 1.15-1.55), with stronger effects for Crohn disease. The IBD-CRC association was positive but heterogeneous (RR 1.36, 95% CI, 1.14-1.62). A 2-stage mediation model suggested a small indirect UPF to CRC effect via IBD (approximate RR 1.07). Higher UPF consumption is therefore associated with modestly increased risks of IBD and CRC, although the indirect effect through IBD appears limited.
Systematic Review Registration:
PROSPERO registration No. CRD420251035864.
More Related Videos
Related Concept Videos
02:59Cancer Prevention
Some...
01:27Inflammatory Bowel Disease I: Ulcerative Colitis
Inflammatory bowel disease, or IBD, encompasses a group of disorders characterized by chronic inflammation or ulceration of the gastrointestinal tract.
Risk Factors
The exact cause of IBD remains unclear, although it is believed to be due to a mix of genetic, environmental, microbial, and immune factors. Genetic factors are significant in determining susceptibility to IBD, with family history being a critical risk factor. Individuals with a first-degree relative who has IBD are at...
01:30Inflammatory Bowel Disease III: Diagnostic Studies and Management I-Nutritional Therapy
Diagnostic studies
A colonoscopy is the definitive screening test, distinguishing ulcerative colitis from other colon diseases with similar symptoms. During a colonoscopy test, inflamed mucosa with exudate ulcerations can be observed, and biopsies are taken to determine the histologic characteristics of the...