Risk Factors

The causes of breast cancer are not known currently. However, factors have been researched that will either help increase (or decrease) the chance of getting breast cancer. These are known as risk factors. Some risk factors you can control would be like exercise however, there are some you cannot control. The two most common risk factors are being a woman and getting older although, some are still unknown. However, having some control can allow you to avoid some risk factors.

Most risk factors that you have control over only have a small effect on you getting breast cancer. This also means that no one behavior or avoidance of risk can prevent breast cancer either. But, there is also no one factor that will cause breast cancer either.

Risk factors related to a higher risk of breast cancer:

  • A family history of breast, ovarian or prostate cancer
  • A personal history of breast cancer, including ductal carcinoma in situ (DCIS)
  • Alcohol use
  • Ashkenazi Jewish heritage
  • An inherited BRCA1 or BRCA2 gene mutation
  • Being a woman
  • Being overweight (especially after menopause)
  • Current or recent use of birth control pills
  • Current or recent use (for more than 5 years) of menopausal hormone therapy (postmenopausal hormone use) containing estrogen plus progestin
  • Exposure to large amounts of radiation at young age
  • Getting older- Increases as age increase
  • High breast density on a mammogram
  • Hyperplasia or lobular carcinoma in situ (LCIS)
  • Lack of exercise
  • Never having children or having a first child after age 35
  • Not breastfeeding
  • Older age at menopause
  • Weight gain
  • Younger age at first period