Chang VC, et al. - By performing this population-based case-control study in Ontario, Canada, researchers examined the links between iron consumption and breast cancer risk, overall and by menopausal and estrogen receptor/progesterone receptor (ER/PR) status, and they focused on modification by oxidative stress-associated genetic polymorphisms (MnSOD, GSTM1, and GSTT1). This study included 3,030 cases and 3,402 controls. Overall, no links were identified between iron consumption and breast cancer risk. A positive link of the total, dietary, and dietary non-heme iron, with ER–/PR– breast cancer risk, was revealed among premenopausal women. In postmenopausal women, supplemental iron was found to be related to decreased breast cancer risk, and dietary heme iron was related to an increased risk, especially the ER–/PR– subtype. In females with GSTT1 deletion or GSTM1/GSTT1 double deletions, higher dietary iron was most strongly related to elevated breast cancer risk. As per the findings, distinct effects of iron consumption on breast cancer risk may be seen by menopausal and hormone receptor status, as well as genotypes influencing antioxidant capacity.