Beneath the Surface: The Emerging Role of Ultra-Processed Foods in Obesity-Related Cancer

Abstract

Purposeof review: Ultra-processed foods (UPFs) are becoming more and more important in daily diets around the world; in some cases, they can account for as much as 60% of daily energy intake. Epidemiological evidence suggests that this shift toward high levels of food processing may be partially responsible for the global obesity epidemic and the rise in the prevalence of chronic diseases.

Recent findings: Few prospective studies have examined the relationship between UPF consumption and cancer outcomes. According to currently available information, UPFs may increase the risk of cancer due to their obesogenic properties and exposure to substances that can cause cancer, such as certain food additives and pollution from product processing. The complex relationship between obesity and cancer involves factors such as immune dysregulation, altered adipokine and sex hormone levels, abnormal fatty acid metabolism, extracellular matrix remodeling, and chronic inflammation. Addressing cancer risk associated with UPF consumption could involve a multifaceted approach, including consumer behavior modification programs and robust public health regulations aimed at enhancing food environments. Improved knowledge of the potential dual negative impacts of UPFs on the environment and cancer risk is one of the priority areas we identify for future research and policy implications. Various approaches could be used to prevent cancers associated with UPF consumption, such as consumer behavior change programs and stricter public health regulations needed to improve the food environment. This review examines for the first time the potential role of UPFs in cancer risk associated with obesity, exploring underlying biological mechanisms and identifying key areas for future research and policy action, including the dual environmental and health impact of UPFs.

Keywords: Cancer; Chronic low-grade inflammation; Gut microbiome; Obesity; Ultra-processed foods.

Fig. 1

Key factors linking obesity to cancer. Abbreviations: IGF-1: Insulin-like growth factor 1; Created in BioRender. Anastasiou IA. (2025) https://BioRender.com/j66y658. Assessed on 18 January 2025

Fig. 2

Key factors and mechanisms linking ultra-processed foods to obesity-related cancer. Abbreviations: BPA: Bisphenol A; HAAs: Heterocyclic Aromatic Amines; HCAs: Heterocyclic Amines; PAHs: Polycyclic Aromatic Hydrocarbons; SFAs: Saturated Fatty Acids; TFAs: Trans Fatty Acids; UPFs: Ultra-Processed Foods. Created in BioRender. Kounatidis, D. (2024) https://BioRender.com/w42t709. Assessed on 14 December 2024

Fig. 3

From UPF overconsumption to obesity-associated cancer: The potential role of gut dysbiosis. UPFs contain emulsifiers such as CMC, P-80, and CGN, which disrupt the intestinal epithelial barrier by impairing TJ proteins. This impairment contributes to the development of gut dysbiosis, characterized by a compromised barrier integrity known as “leaky gut.” The resulting increased permeability allows pathogenic microbes and toxins from the gut lumen to enter the bloodstream, leading to endotoxemia marked by elevated LPS levels from gram-negative bacteria. This breach triggers an inflammatory response, upregulating pro-inflammatory cytokines and sustaining a chronic low-grade inflammatory environment. Inflammation and endotoxemia are associated with altered gut microbiota diversity and composition, promoting conditions like weight gain, obesity, metabolic syndrome, and an increased risk of obesity-related cancers. Abbreviations: CGN: Carrageenan; CMC: Carboxymethylcellulose; LPS: Lipopolysaccharides; P-80: Polysorbate-80; TJ: Tight junction; UPFs: Ultra-processed foods. Created in BioRender. Kounatidis, D. (2024) https://BioRender.com/g05j455. Assessed on 14 December 2024