Very recently, Caffa et al. demonstrated that periodic fasting or a FMD potentiates the anticancer activity of the endocrine treatment (ET) with tamoxifen and fulvestrant in vitro, in HR+ /HER2—breast cancer cell lines, and in vivo, in mouse xenografts of HR+ breast cancer cell lines and in human HR+ breast cancer organoids. This evidence concerns the gene ERBB2 and breast carcinoma.