Although the exact cause is not known, breast cancer typically starts with genetic material (DNA) mutations which are either inherited or developed from lifestyle and/or environment. Certain factors that are linked to increased risk of breast cancer include: older age, history of breast disease, BRCA1 and BRCA2 genes, obesity and alcohol use. Also, increased exposure to estrogen increases the risk of breast cancer and occurs in conditions such as early menstruation, late menopause, hormone therapy for menopause, and either never giving birth or giving birth at an older age.[1]
What causes breast cancer?
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•Last Updated: May 16, 2025
Breast cancer is caused by DNA mutations that can be inherited or developed from lifestyle and environmental factors. Risk factors include older age, personal history of breast disease, genetic mutations like BRCA1 and BRCA2, obesity, alcohol use, and increased estrogen exposure from various life conditions.