Risk is not caused by one thing
Age, family history, inherited genetic variants, reproductive history, alcohol, body weight after menopause and other factors can affect breast-cancer risk. Having a risk factor does not mean a person will develop cancer, and many people diagnosed have no obvious high-risk history.
Know what is normal for you
Breast awareness means noticing a new lump, thickening, nipple inversion, bloody discharge, persistent one-sided pain, skin dimpling or a change in breast shape. These changes are often benign, but they deserve assessment.
Screening mammography
Screening recommendations differ by country and organization. In the United States, the USPSTF recommends biennial mammography for women aged 40–74. People at higher genetic or family risk may need earlier imaging or MRI.
Risk reduction
Regular physical activity, avoiding or limiting alcohol, maintaining a healthy weight and discussing hormone therapy when relevant can influence risk. People with very high inherited risk may be offered medication or preventive surgery after specialist counseling.