Your chances of developing breast cancer increases if you have certain risk factors. However, it does not mean that you will definitely develop breast cancer if you have one or more risk factors, nor does it mean that you will absolutely not develop breast cancer if you have no risk factors at all. Risk factors only make developing breast cancer more likely.
Breast cancer myths
There are many misconceptions about breast cancer risk factors. Before we talk about what things that are considered risk factors, let’s mention which are definitely not.
Studies have shown that none of the following increase your chances of developing breast cancer, nor can they cause breast cancer:
- underarm products such as antiperspirant and deodorant (These are safe to use and do not affect the tissue inside your breast at all.)
- breast implants (The materials used for breast implants nowadays are very safe and have a minimal risk of leaking.)
- using underwire bras
- drinking coffee or other caffeine-containing drinks (There has been no link found between caffeine and breast cancer)
- having an abortion or a miscarriage
- having multiple pregnancies
- having a condition known as fibrocystic disease, also known as fibrocystic change (Although this condition may also present with lumps or bumps in your chest, it does not increase your chances of developing breast cancer in the future.)

What then are truly considered risk factors for breast cancer?
The risk factors for breast cancer can be divided into two general types: hormonal and non-hormonal. Studies have shown that high levels or long-term exposure to the female hormone estrogen can increase your risk for developing breast cancer. Estrogen is produced when you have your period. The more menstrual cycles you have, the longer you are exposed to estrogen. The following increase the number of menstrual cycles you experience during your lifetime, and, therefore, considered hormonal risk factors for breast cancer:
- having your first period at an early age (12 old or younger)
- undergoing menopause late in life (55 years of age or older)
- never having children
- having your first child at age 35 or older
Other hormonal risk factors can increase the levels of estrogen in your body, such as:
- Obesity. Fat (especially around your abdomen) converts substances into estrogen. This leads to estrogen being present in your body even after menopause.
- Hormone replacement therapy (HRT) for menopause. However, your risk for developing breast cancer decreases once you stop using HRT. If you stop using HRT for five years or more, your risk decreases to the same level as if you had never used HRT at all.
Nonhormonal risk factors include radiation exposure, genetics, certain breast conditions, and alcohol consumption.
Radiation exposure
You may have been given radiation therapy for conditions such as lymphoma. Radiation exposure may also come in the form of prolonged fluoroscopic X-rays. This puts you at a slightly higher risk for developing breast cancer.
Genetic factors
Breast cancer has been shown to run in certain families. If a first degree relative (mother, sister, or daughter) of yours develops breast cancer, the chances of you having the same disease go up. The risk is increased if your first degree relative had breast cancer before going through menopause, or if she had cancer present in both breasts. Having any male relative that has breast cancer also puts you at a higher risk. The risk is not as high if more distant family members such as grandmothers, aunts, or cousins have the disease. However, the risk is still present.
Two genes have been identified as related to the development of breast cancer. If you have mutations in the genes BRCA1 or BRCA2, there is around an 80% chance that you will have breast cancer. You may undergo genetic testing to see if you have these mutations.
Other genes that increase the risk of developing other cancers may also increase your risk for breast cancer. If other members of your family have other kinds of cancer, your risk for breast cancer may go up as well. The Li Fraumeni syndrome involves mutations in a gene called p53. This syndrome puts you at an 85% to 90% risk for breast cancer. Other cancers associated with this syndrome are brain tumors, osteosarcoma (cancer in the bone), and leukemia, among others.
The Cowden syndrome is caused by mutations in the PTEN gene and is associated with thyroid cancer as well as endometrial cancer (cancer affecting the lining of the uterus). Having this syndrome puts you at a risk of developing breast cancer to as high as 50%.
Other conditions affecting the breast
You are at a greater risk for breast cancer if you have been previously diagnosed with any of the following conditions:
- atypical hyperplasia, either lobular or ductal
- sclerosing adenosis
- solitary papilloma
- fibroadenomas with complex features
- hyperplasia without atypia
Excessive alcohol intake
Drinking more than two alcoholic beverages a day increases your risk of developing breast cancer. This risk further increases for menopausal women.
Previous breast cancer
If you have had breast cancer in the past, this puts you at a significantly higher risk for developing breast cancer once again. This new breast cancer is not related to the previous disease. It does not mean that your old breast cancer has recurred, or that treatment has failed.
