Diet and breast cancer: New perspectives on nutrition, metabolism, and immunity.

Breast cancer is one of the most common malignant tumors among women worldwide. Despite the continuous development of various treatment strategies, including surgery, chemotherapy, endocrine therapy, targeted therapy, and immunotherapy, tumor heterogeneity, metabolic adaptation, and immune escape continue to challenge treatment efficacy and may contribute to drug resistance. Recent studies suggest that metabolic reprogramming of tumor cells and the immune status of the tumor microenvironment play a role in the sensitivity of breast cancer to treatment. Diet, as an important regulator of nutrition and metabolism, may influence tumor treatment response through multiple mechanisms. This review provides a concise overview of the potential mechanisms through which dietary factors may influence the treatment sensitivity of breast cancer from the perspective of integrated nutrition, metabolism and immunity. It focuses on the research progress of dietary patterns and natural dietary bioactive components in regulating tumor metabolism, the immune microenvironment, and treatment sensitivity. Furthermore, the gut microbiota may serve as an important mediator connecting nutrient intake, host metabolism, and immune responses, with potential implications for breast cancer treatment response through its metabolites and immunomodulatory effects. In conclusion, dietary intervention and its associated metabolic regulation may provide potential adjunctive approaches that warrant further clinical investigation for the treatment of breast cancer. This review would provide insights for further elucidating key molecular mechanisms and conducting clinical research.