The efficacy of functional foods in stages of gastrointestinal cancer is evidenced by compounds such as prebiotics, probiotics, antioxidants, phenolic compounds, and dietary fibers. Objective: To evaluate the influence of functional foods on the treatment of gastrointestinal cancer. Methodology: This was a bibliographic study of an exploratory-descriptive type with a qualitative approach. The data collection began with a bibliographic survey conducted through research of scientific productions on the proposed theme, covering the period from 2014 to 2024. The literature search was carried out in the following databases: Latin American and Caribbean Health Sciences Literature (LILACS) and PubMed. It is noteworthy that the LILACS and BDENF databases were consulted through the Virtual Health Library (VHL). The searches were conducted using the Descriptors: Intestinal Neoplasms, Functional Foods, and Gastrointestinal Cancer, in Portuguese and English, with the aid of the Boolean operator "AND". Results and Discussion: Functional foods have chemopreventive properties, inhibiting the proliferation of cancer cells and promoting apoptosis. They are most effective in the early stages of the disease and may include probiotics and prebiotics to maintain intestinal health and reduce the adverse effects of chemotherapy. They also modulate the microbiome, improving the efficacy of treatments and aiding in the recovery of microbial diversity during oncological treatment. Conclusion: Dietary strategies that include prebiotics, probiotics, polyphenols, and fibers can optimize therapeutic outcomes and improve the quality of life of patients with gastrointestinal cancer.
