Risk Factors You Should Know
Did you know that 1 in 8 women are diagnosed with breast cancer during their lifetime and 1 in 39 will die from this disease?
Known risk factors for developing breast cancer can either be lifestyle-related (meaning you CAN change your risk) or related to things that are out of your control.
Risk Factors you CAN change
- Alcohol consumption. The more alcohol you drink, the higher the risk of developing breast cancer.
- Smoking. Smoking increases the risk of breast cancer among younger, premenopausal women. Smoking can also cause complications with breast cancer treatment.
- Inactivity and sedentary behavior. Evidence shows that being physically active reduces the risk of breast cancer. The American Cancer Society recommends that adults get 150–300 minutes of moderate activity or 75–150 minutes of vigorous activity weekly.
- Breastfeeding. Studies suggest that women who do not breastfeed might have a slightly higher risk of developing breast cancer; conversely, breastfeeding can slightly decrease your risk.
- Oral birth control pills. Most studies confirm that taking oral birth control pills slightly increases the risk of breast cancer over women who have never taken them.
- Children. Nulliparous (not having children) OR having your first child after age 30 increases your risk. Having multiple children or having your first child at an early age, decreases your risk.
- Obesity. Being overweight or obese after menopause increases your risk of breast cancer. After menopause, fat tissue becomes women’s main source of estrogen. Having more fat tissue, then, can elevate estrogen levels and increase the risk of breast cancer.
Risks you CANNOT change
- Birth sex. Men can get breast cancer, but the incidence is much smaller than in women. Simply being female puts you at an increased risk for breast cancer.
- Early menstrual cycle (especially before 12 years of age) or late menopause (after age 55). Likely related to a longer lifetime exposure to hormones (estrogen and progesterone).
- Increasing age. Most breast cancer is diagnosed in women who are 55 or older.
- Race and ethnicity. Caucasian and African American women have a greater risk for breast cancer over Hispanic, Asian, and Native American women.
- Height. Women who are taller (over 5’3″) have an increased risk of developing breast cancer; the reason behind this link has not been established.
- Personal or family history. Women who have cancer in one breast are at an increased risk for developing cancer in the other breast. Fifteen percent of all cases have a family member with a history of breast cancer. Having a first-degree relative (mother, sister, daughter) almost doubles your risk, while having two first-degree relatives with that history nearly triples the risk.
- Genetics. Roughly 5–10% of breast cancer cases are related to mutations in genes that were inherited. The most common inherited causes are BRCA1 and BRCA2 mutations. If you are a woman with either BRCA1 or BRCA2 gene mutation your risk of developing breast cancer by the age of 80 increases to 7 in 10. Additionally, a woman who has these mutations is also more likely to develop ovarian cancer. Genetic testing can be done to identify these mutations in women with higher risks of breast cancer.
- Chest radiation therapy. Teens and young adults who have had radiation therapy on their chests to treat other cancers have a “significantly higher risk” for developing breast cancer, according to the American Cancer Society.
The American Cancer Society recommends women with an average risk (NO personal history of breast cancer, NO family history, NO known genetic mutation, and NO history of chest radiation therapy before the age of 30) be screened as follows:
- Optional screening mammogram annually for women between the ages 40–44.
- Annual mammograms for women ages 45–54.
- For women ages 55 and older, a mammogram every year or every other year.
Mammograms are X-rays of the breast and are considered the best practice for early detection of breast cancer.
The American Cancer Society recommends women who are at high risk of developing breast cancer get a breast MRI in addition to a mammogram every year starting at age 30.
Some high-risk factors include:
- Lifetime risk of breast cancer of 20–25% or more.
- First-degree relative with either the BRCA1 or BRCA2 gene mutation.
- Known BRCA1 or BRCA2 gene mutation.
- History of chest radiation between the ages of 10 and 30 years.
A breast MRI (magnetic resonance imaging) takes detailed images of the breast; when paired with a mammogram, the two detection methods complement each other in finding cancer. Breast MRIs are not recommended for women with a 15% or less lifetime risk of breast cancer.
At the time of diagnosis, roughly 64% of breast cancer patients have “local disease,” meaning the cancer has not spread. Breast cancer typically does not give symptoms early in the disease when the cancer is small and has not spread, which makes regular mammograms for early detection VERY important. Early detection is crucial to good outcomes. Speak with your healthcare provider about breast cancer screening.
American Cancer Society, “American Cancer Society Recommendations for the Early Detection of Breast Cancer,” https://www.cancer.org/cancer/breast-cancer/screening-tests-and-early-detection/american-cancer-society-recommendations-for-the-early-detection-of-breast-cancer.html
American Cancer Society, “Breast Cancer Facts & Figures 2019-2020,” https://www.cancer.org/content/dam/cancer-org/research/cancer-facts-and-statistics/breast-cancer-facts-and-figures/breast-cancer-facts-and-figures-2019-2020.pdf
American Cancer Society, “Breast Cancer Risk Factors You Cannot Change,” https://www.cancer.org/cancer/breast-cancer/risk-and-prevention/breast-cancer-risk-factors-you-cannot-change.html
American Cancer Society, “Breast MRI,” https://www.cancer.org/cancer/breast-cancer/screening-tests-and-early-detection/breast-mri-scans.html
American Cancer Society, “Lifestyle-related Breast Cancer Risk Factors,” https://www.cancer.org/cancer/breast-cancer/risk-and-prevention/lifestyle-related-breast-cancer-risk-factors.html
Breastcancer.org, “Smoking,” https://www.breastcancer.org/risk/factors/smoking