A positive link between fat intake and estradiol levels has been noted in the present study, in which 84% of cases were estrogen-related BC, and in the prospective WHI DM study, which found a statistically significant reduction in BC risk after the implementation of low-fat DP only for estrogen receptor (ER)-positive and progesterone receptor (PR)-negative tumors (HR, from 0.64 through the 0.70 to 0.77) [17,18,24,29]. Here, ESR1 is linked to breast cancer.