This systematic review was conducted by the 2025 Dietary Guidelines Advisory Committee as part of the process to develop the Dietary Guidelines for Americans, 2025–2030. The U.S. Departments of Health and Human Services (HHS) and Agriculture (USDA) appointed the 2025 Dietary Guidelines Advisory Committee (Committee) in January 2023 to review evidence on high priority scientific questions related to diet and health. Their review forms the basis of their independent, science-based advice and recommendations to HHS and USDA, which is considered as the Departments develop the next edition of the Dietary Guidelines. As part of that process, the Committee conducted a systematic review with support from the USDA Nutrition Evidence Systematic Review (NESR) team to answer the following question: What is the relationship between dietary patterns consumed and risk of breast cancer? This review is an update to existing reviews that was conducted by the 2020 Dietary Guidelines Advisory Committee.
