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Underexplored Environmental Factors and Gut Microbiome Alterations as a Pathogenic Pathway in Early-Onset Intestinal Cancer: An Analytical Literature Review

Hicham ELLOUAD, Anass BELBACHIR, Bouchra ASSARAG, Anass Doukkali, Assia SAYDTAHIRI
1Laboratory of Excellence in Biotechnology, Pharmaceutical Bioengineering, and Artificial Intelligence, FMPM, Cadi Ayyad University, Marrakech, Morocco.
2Public Health Department, ENSP, Madinat Al Irfan, Rabat, Morocco.
3Laboratory of Analytical Chemistry, Faculty of Medicine and Pharmacy, Mohammed V University in Rabat, Morocco.
4LARTID, ENSA, Cadi Ayyad University, Abdelkrim El Khattabi Avenue, Marrakech, Morocco.
h.ellouad.cd@uca.ac.ma, an.belbachir@uca.ac.ma, bassarag1@gmail.com, doukali73@gmail.com, a.saydtahiri.cd@uca.ac.ma
How to cite: Hicham ELLOUAD, Anass BELBACHIR, Bouchra ASSARAG, Anass Doukkali, Assia SAYDTAHIRI, Underexplored Environmental Factors and Gut Microbiome Alterations as a Pathogenic Pathway in Early-Onset Intestinal Cancer: An Analytical Literature Review, Sciences Methods and Technologies International Journal (SciMeTech), (2026) Vol 2, Issue 2, p 62-68
Abstract
Background and Objectives: Early-onset intestinal cancers are rising at an alarming rate, a trend not fully explained by established risk factors alone. This review examines four under-studied environmental factors - antibiotics, pollutants and pesticides, infant formula, and food additives - as potential drivers of early-onset intestinal cancer through gut dysbiosis.

Methods: A systematic search across PubMed, Scopus, Web of Science, and Google Scholar (2015-2026) yielded 67 selected publications spanning randomized controlled trials, cohort studies, case-control designs, experimental models, systematic reviews, and meta-analyses.

Results: Broad-spectrum antibiotics, particularly during childhood, chronically deplete butyrate-producing bacteria while promoting the growth of cancer-associated species such as Fusobacterium nucleatum. Environmental toxins disrupt microbial composition through specific pro-inflammatory signaling pathways. Industrial infant formula, lacking human milk oligosaccharides and epithelial growth factors, impair gut immune maturation with effects persisting into adulthood. Food additives including emulsifiers, preservatives, and artificial dyes degrade the mucosal barrier, select for inflammation-promoting bacteria, and activate carcinogenic pathways across multiple generations.

Conclusion: These factors share a common mechanism: the dysbogenic exposure, defined as the multigenerational accumulation of environmental aggressions, progressively degrading the intestinal microbial ecosystem. This interpretive framework suggests that rising early-onset intestinal cancer rates reflect cumulative gut microbiome disruption beginning early in life, rather than isolated exposures. Prospective longitudinal studies incorporating repeated microbiome assessments and early-life exposure data are needed to validate this model and guide primary prevention.
Keywords: Early-onset intestinal cancer, Gut microbiome dysbiosis, Environmental exposures, Food additives, Intestinal inflammation

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SciMeTech · Vol 2, Issue 2 · p 62-68