Globally, breast cancer is the second-most common cause of cancer-related deaths among women. Recent research suggests that the gut microbiome may influence the development of breast cancer via hormonal, immunological, and metabolically mediated pathways. This review systematically summarizes the literature on the differences in gut microbiome diversity between women with breast cancer and without breast cancer. Women with breast cancer show consistently lower alpha diversity than women without breast cancer, particularly in postmenopausal women and those with metabolic dysfunction. These patterns suggest that gut microbiome diversity serves as an ecosystem-level indicator that interacts with the host context rather than acting as a standalone biomarker risk. This review also identifies the limitations in the current literature and the limitations of this review. For example, the evidence presented here is based on cross-sectional observational studies, and the methods for analyzing gut microbiota are highly heterogeneous. This review is non-systematic, focusing solely on gut microbiota diversity rather than functional/multi-site datasets. The insights presented in this review underscore the need for large, longitudinal studies of ethnically diverse cohorts and standardized methods to assess gut microbiota diversity, with the goal of determining how modifying gut microbiota diversity could provide a basis for developing personalized prevention/management strategies for breast cancer.

Due to observational studies on the role of type of food in have been inconsistent, the objective of this study was to apply the MR framework to evaluate the causal link between dietary intake and gastric ulcer to provide suggestions for preventive intervention strategies. Mendelian randomization test was conducted to assess the impact of 26 types of dietary habits and macronutrient intake on of GC and precancerous lesions. Genetically predicted alcoholic drinks per week were strongly connected with. Potential evidence , fat, and cooked vegetable intake might increase tumors. Salad/raw vegetable intake may decrease . Dietary composition and habits are causally related to GC and precancerous lesions. The biological heterogeneity of food processed in different ways and type of food may be a risk factor for GC. Intensive attention should be paid to lifestyle and diet management.