Arriaga ME, et al. - Using adjusted proportional hazards models, researchers evaluated breast cancer burden for premenopausal and postmenopausal women in Australia relative to individual and combinations of behavior modifications and if these effects varied across population subgroups by linking pooled data from six Australian cohort studies (214,536 participants) to national cancer and death registries. Ten years follow-up revealed 640 incident breast cancers in premenopausal women, 2,632 in postmenopausal women, and 8,761 deaths due to any cause. For premenopausal women, 12.6%, 7.1%, and 18.8% of future breast cancers were explained by any regular alcohol consumption, current use of oral contraceptives for ≥5 years, and the combination of these factors, respectively. For postmenopausal women, 12.8%, 6.9%, 6.6%, and 24.2% of future breast cancers were explained by overweight or obesity (BMI ≥25 kg/m2), current use of menopausal hormone therapy (MHT), any regular alcohol consumption, and combination of these factors, respectively. By body fatness, alcohol consumption and socio-economic status, the postmenopausal breast cancer burden attributable to MHT varied. Variations were seen in the body fatness-related postmenopausal breast cancer burden by alcohol consumption and educational attainment, and the alcohol-related postmenopausal breast cancer burden by breast feeding history. Targeted and population-level cancer control activities should be encouraged.