What causes breast cancer?

What causes breast cancer?

Breast cancer develops when abnormal cells in your breast divide and multiply. But experts don’t know exactly what causes this process to begin in the first place.

However, research indicates that are several risk factors that may increase your chances of developing breast cancer. These include:

• Age. Being 55 or older increases your risk for breast cancer.
• Sex. Women are much more likely to develop breast cancer than men.
• Family history and genetics. If you have parents, siblings, children or other close relatives who’ve been diagnosed with breast cancer, you’re more likely to develop the disease at some point in your life. About 5% to 10% of breast cancers are due to single abnormal genes that are passed down from parents to children, and that can be discovered by genetic testing.
• Smoking. Tobacco use has been linked to many different types of cancer, including breast cancer.
• Alcohol use. Research indicates that drinking alcohol can increase your risk for certain types of breast cancer.
• Obesity. Having obesity can increase your risk of breast cancer and breast cancer recurrence.
• Radiation exposure. If you’ve had prior radiation therapy — especially to your head, neck or chest — you’re more likely to develop breast cancer.
• Hormone replacement therapy. People who use hormone replacement therapy (HRT) have a higher risk of being diagnosed with breast cancer.

There are many other factors that can increase your chances of developing breast cancer. Talk to your healthcare provider to find out if you’re at risk.