Current Evidence on the Impact of Diet, Food, and Supplement Intake on Breast Cancer Health Outcomes in Patients Undergoing Endocrine Therapy

Background: /Objectives: The most common breast cancer (BRC) in women is estrogen/progesterone receptor-positive. The first-conventional treatment includes endocrine therapy either with aromatase inhibitors or tamoxifen to reduce estrogen levels. These treatments are associated with side effects, the most typical being joint/muscle pain, known as aromatase inhibitor arthralgia, affecting overall health and quality of life (QoL). The objectives here were to evaluate interventions examining impact of modified diets, supplements, and/or some food components on health outcomes in BRC patients undergoing endocrine therapy. Methods: Literature search was performed in PubMed, Scopus, and Web of Science through the end of November 2024, with articles reporting intervention with diet/food/supplement intake and the relevant outcomes. Results: The search uncovered 1028 studies; after the removal of duplicates, abstracts, and irrelevant studies, 53 studies were closely examined, with 26 evaluated and presented here. The outcomes were changes in bone and body composition, cardiovascular disease risks, inflammation, and QoL. Conclusions: Examined evidence suggests that adherence to dietary patterns such as Mediterranean or low-fat diet, and higher intake of fruits and vegetables were beneficial for various outcomes. Additionally, supplementation with some foods/components (dried plum, red clover), contributed to improving/maintaining bone and body composition, especially in overweight/obese patients. Supplementation with vitamin D or omega-3 improved lipid and angiogenic parameters and QoL. Although these results are promising, the effects of each supplement/food cannot be summarized due to the diverse nature of study designs, patients, and supplement dosage. Further studies are needed to explore the effects of specific nutritional interventions on various health outcomes in BRC survivors during endocrine therapy and derive universal recommendations.