Breast cancer occurs when abnormal breast cells divide and multiply out of control (abnormal cell division).
Many people have abnormal cells. It isn’t clear what triggers abnormal cells to begin dividing in some people.
According to Health.com, researchers know that certain hormones, genetics, lifestyle, and environmental risk factors can increase the likelihood of breast cancer.
A new study shows the breast cancer rate among women 50 and over is rising dramatically.
What Causes Breast Cancer?
Normal cells such as skin cells constantly divide and renew in a process called skin regeneration. But abnormal cells divide rapidly and grow out of control in an abnormal way.
As abnormal cells divide, they clump together in a mass or tumor that develops its own blood supply. The cancer may spread to other organs (metastatic cancer).
Most breast cancers in women and men start in the milk ducts. This is called invasive ductal carcinoma. Men have milk ducts that do not produce milk due to low female hormones.
Other breast cancers start in breast tissue cells, including glandular tissue called lobules; this is called invasive lobular carcinoma.
Breast Cancer Risk Factors
Breast cancer risk factors include certain hormones, genetics, lifestyle, and environmental risk factors. More causes of breast cancer are listed below.
Age
The risk increases with age, which is why the American College of Obstetricians and Gynecologists recommends yearly mammograms starting at age 40.
Genetics
Risk factors increase if a woman has a close family member with a history of breast cancer.
Alcohol
Women who drink alcohol have an increased risk of breast cancer.
Sugar consumption
Drinking too many sugary beverages (sodas) may increase the risk of death from cancer.
Age of 1st menstruation cycle
Women who began menstruating before age 12 are at increased risk of breast cancer.
Pregnancy
Giving birth to your first child after age 30 can increase your breast cancer risk. But women who have never been pregnant are at a greater risk of breast cancer.
Hormones
Hormone replacement therapy (HRT) can increase the risk of breast cancer, specifically estrogen and progesterone combination.
Obesity
Obesity increases the risk of breast cancer in postmenopausal women. Obesity is defined as having a body mass index (BMI) of 30 or higher. A BMI of 25 or higher is considered overweight.
Your BMI is determined by entering your height and weight into a BMI calculator such as Harvard Health’s BMI calculator.