Emerging Links Between Diet, Microbiome, and Gastric Cancer Risk

Recent research from The Chinese University of Hong Kong (CUHK) reveals critical insights into the relationship between diet, the gut microbiome, and the rising incidence of gastric cancer (GC) among younger individuals in developed countries. Gastric cancer, a significant global health concern, ranks as the fifth most frequent cancer and the third leading cause of cancer-related mortality, accounting for over 784,000 deaths annually. Traditionally associated with older populations, the increasing prevalence of GC in younger demographics underscores a shift in risk factors that necessitates thorough investigation.

According to Professor Jun Yu, from the State Key Laboratory of Digestive Disease at CUHK, the study, published on May 12, 2025, in the journal Research, highlights how specific dietary patterns and gastric microorganisms interact in ways that can promote or hinder the development of GC. The research team conducted an extensive review of various studies to assess how dietary habits, gastric microbes, and their metabolites influence cancer risk.

The findings illustrate that high-salt diets, particularly those rich in salt-preserved foods prevalent in various Asian cuisines, damage the stomach lining and create conditions conducive to the growth of harmful bacteria. Processed meats, when cooked at high temperatures, generate carcinogenic compounds, while excessive alcohol intake produces toxic metabolites that compromise cellular integrity in the stomach. Furthermore, high-fat diets have been linked to increased inflammation and tumor progression.

The study also emphasizes the role of Helicobacter pylori, a bacterium infecting nearly half of the global population, as a primary risk factor for GC. However, it points out that only a minority of those infected actually develop cancer, suggesting that additional factors—particularly the complex interplay of gut microbiota—may be pivotal in determining cancer susceptibility.

Emerging technological advancements, particularly in microbial profiling, have facilitated deeper investigations into the microorganisms residing in the gastric mucosa. The review identifies harmful bacteria such as Streptococcus anginosus and Fusobacterium nucleatum as contributors to cancer development by producing toxic chemicals and promoting inflammation, thereby aiding tumors in evading immune responses. Conversely, beneficial bacteria like Akkermansia muciniphila and certain butyrate-producing species are recognized for their protective roles against cancer by bolstering immune responses and maintaining healthy stomach environments.

Professor Yu emphasizes the potential for dietary interventions, suggesting that a diet rich in fruits and vegetables while minimizing processed meats and salty foods could significantly lower GC risk. Additionally, compounds found in various foods, such as broccoli sprouts, have shown promise in reducing H. pylori colonization, while walnuts may exhibit anti-cancer properties through inflammation reduction and cellular defense enhancement.

Looking forward, the research indicates that personalized dietary modifications and microbiome-based therapies could offer new avenues for GC prevention. Such strategies may include engineered probiotics aimed at outcompeting harmful bacteria or precision nutrition approaches tailored to individual microbiome profiles. This comprehensive analysis not only charts a roadmap for future gastric cancer research but also underscores the urgent need for developing effective public health strategies to address the rising global burden of this disease. As the landscape of gastric cancer continues to evolve, these insights may pave the way for innovative treatment and prevention methodologies, ultimately contributing to better health outcomes worldwide.