Each year, more than 232,000 women in the U.S. are diagnosed with breast cancer.1 That means that about every two minutes, another woman has her life turned upside down by this disease.
While there’s no surefire way to prevent breast cancer altogether, there’s a lot we can do to protect ourselves from the disease.
Risk Factors That You Can Control
Leading an active, healthy lifestyle can reduce the risk of breast cancer and improve our overall wellness. The earlier you focus on adopting healthy habits, the better, but it’s never too late to start. Behaviors that affect our risk of developing breast cancer include the following:
- Alcohol. Even moderate drinking increases the risk of breast cancer: each 10-gram (slightly less than one drink) increase in daily alcohol consumption increases the risk of breast cancer by 7 to 10 percent.2, 3 This is a fairly modest, but statistically significant amount, which can translate into many additional cases on a population level.
- Physical activity. In addition to reducing your risk of developing breast cancer, regular physical activity improves survival after a breast cancer diagnosis. Vigorous physical activity appears to have the most significant effect on reducing breast cancer risk, but activities such as brisk walking also provide a benefit.4
- Body weight. In premenopausal women, obesity has been linked with a decreased risk of breast cancer,5 possibly as a result of disrupted menstrual cycles and altered hormone levels. After menopause, however, obesity is linked with an increased risk of breast cancer.6 This may be due to higher estrogen levels in heavier postmenopausal women. Studies suggest that overweight postmenopausal women who lose weight and keep it off can reduce their risk.7
- Breastfeeding. Breastfeeding, and in particular longer-term breastfeeding, has been linked to a reduced risk of breast cancer.8
- Postmenopausal hormones. The effect of postmenopausal hormone therapy on breast cancer risk appears to vary by the type of hormone therapy: combined estrogen plus progestin has been linked with an increased risk of breast cancer, but estrogen alone has not.9 Because estrogen alone can cause endometrial (uterine) cancer, it is generally only used by women who have had a hysterectomy.
- Oral contraceptives. Some studies have reported a small increase in risk of breast cancer among women who use birth control pills, but birth control pills also significantly reduce the risk of ovarian cancer.10
Risk Factors That You Can’t Change
When it comes to managing our risk for breast cancer, there’s a lot we can do, but there are also many risk factors — such as being a woman and getting older — that are out of our control. Being aware of these factors can help us understand and manage our risk.
- Family history. Having a family history of breast cancer can increase your risk. Breast cancer in a close relative (your mother or sister, for example) increases your risk to a greater extent than breast cancer in a more distant relative, particularly if the cancer is diagnosed at a young age.
- Breast density. Breast density can be evaluated by mammography and refers to the extent of glandular and connective tissue in the breasts. Breasts with more glandular and connective tissue—and less fat—have higher density. Women with high breast density have an increased risk of developing breast cancer.11
- Benign breast disease. Benign breast disease refers to several types of non-cancerous changes in breast tissue. Although some of these breast changes have very little (or no) effect on breast cancer risk, others — particularly atypical hyperplasia — are linked with increased risk.12 In atypical hyperplasia, the number of cells within the ducts or lobules of the breast is increased, and these cells appear abnormal under the microscope.
- Radiation to the chest. Women who receive radiation therapy to the chest at a young age for the treatment of Hodgkin’s lymphoma or other cancers have an increased risk of breast cancer.13
- Reproductive factors. Early age at first menstrual period, late age at the birth of your first child, and late age at menopause each increase the risk of breast cancer.
Myths About Breast Cancer Risk Factors
At one time or another, the following exposures have been in the news (or circulated on the Internet) as possibly linked with breast cancer. The best available evidence, however, suggests that these factors do not affect the risk of breast cancer.
- Underwire bras. Most experts agree that it’s simply not plausible that wearing a bra would affect your risk of breast cancer.17 Restriction of the breasts would not be expected to affect hormone levels or other factors linked with breast cancer development.
- Antiperspirants. Internet rumors fueled concerns about a possible link between underarm antiperspirants/deodorants and breast cancer, but the National Cancer Institute has determined that there’s no “conclusive research linking the use of underarm antiperspirants or deodorants and the subsequent development of breast cancer.”18
- Abortion. Some early studies raised concerns about a link between abortion and breast cancer, but this link was not confirmed by later studies.14, 15 In 2009, the American College of Obstetricians and Gynecologists issued a committee opinion that stated, “More rigorous recent studies demonstrate no causal relationship between induced abortion and a subsequent increase in breast cancer risk.”16
Some factors have not yet been conclusively linked with breast cancer, but may be in the future.
- Environmental pollutants. Although the health effects of environmental contaminants are a concern for all of us, it remains uncertain whether exposure to these agents affects breast cancer risk. This is an active area of research, however; scientists continue to explore the effects of many different types of chemicals, including those termed “endocrine disruptors” (chemicals that affect the production or function of hormones such as estrogen).19
- Diet. Diet has received a great deal of attention in relation to breast cancer, but links with breast cancer remain uncertain (with the exception of alcohol, discussed above).
fit for Women
Focus, Inspire, Transform
A healthy, active lifestyle is linked to a lower risk for breast cancer, as well as better survival rates for those who do face a diagnosis. But what does healthy lifestyle really mean? Where do you start?
It’s easier than you think.
fit for Women is a holistic approach, grounded in scientific and behavioral research, that is designed to educate, motivate and inspire women in all stages of life to live a balanced, healthy lifestyle. Centered on four simple tenets — food, move, mood and recharge — fit for Women will empower you to FOCUS on the essential elements of good health, INSPIRE others to live healthfully, and TRANSFORM your body, your health, and the way we approach fighting breast cancer.
While there’s no surefire way to prevent breast cancer altogether, there’s a lot we CAN do to protect ourselves from the disease.
By focusing on four key areas of life, we have a foundation to set goals and start making small, healthy choices.
- FOOD: Your nutritional fitness.
Fueling your body with a balanced diet gives you the energy and, along with exercise, helps keep off the extra pounds that can be harmful to your health.
- MOVE: Your physical fitness.
Studies show that even moderate physical activity, such as one to two hours of brisk walking each week, can help reduce our risk for breast cancer. Sweating it out with vigorous exercise for up to 10 hours each week can reduce risk even further.
- MOOD: Your emotional fitness.
A stressful day can throw everything out of balance, if we let it. And chronic stress can lead to a number of serious health problems. While no one can escape the demands of home and work life, we can learn to manage our emotions in a productive way so that they don’t drag us down.
- RECHARGE: Your behavioral fitness
Women are notorious for exhausting all their energy caring for others. But for the sake of our mental and physical well-being, we need to draw the line somewhere. Catching enough sleep and fitting in regular “me” time to breathe and relax aren’t luxuries–they’re necessities.
All four of these tenets impact your total well-being, and all four interact and influence one another to keep you at the top of your game, and optimize your body’s ability to fight back against cancer. It’s easy to see how a lapse in one area can cause a domino effect, negatively affecting all the other areas.
Remember, there’s more to being fit than just exercise and diet–it’s about striking a healthy balance in mind, body and spirit.
The fit platform was originally developed by Sanford Health and piloted as a national initiative aimed at children, teens and families to promote healthy choices and actions. Its success prompted Edith Sanford to adapt the concept for women to encourage lifestyle choices that can help reduce breast cancer risk.
Family History and Genetics
Five to ten percent of all breast cancer cases are considered hereditary, meaning they’re caused by a faulty gene, like BRCA1 or BRCA2, that is passed down from generation to generation.
BRCA genes and breast cancer
The breast cancer genes, BRCA1 and BRCA2, are normal genes that help repair DNA damage, and therefore help prevent cancer from developing. However, certain harmful mutations can cause them to stop providing that protection–drastically increasing your risk of cancer.
A woman with a BRCA mutation has a 50 to 85 percent chance of developing breast cancer by the time she’s 70. This is a significant risk, especially in comparison to the 12 percent chance faced by women without one of these mutations.
The risk for ovarian cancer also rises. BRCA1 mutations are associated with a 20 to 50 percent chance of developing ovarian cancer by the age of 70, and for BRCA2 mutations, a 10 to 30 percent chance. The average risk for ovarian cancer is only 1.5 percent.
Men who carry one of the defective genes are also at five to ten percent increased risk for breast cancer, and they may be diagnosed with pancreatic cancer at an earlier age than the average man.
Other cancers seen, particularly in people with BRCA2 mutations, are pancreatic cancer, melanoma and prostate cancer in men.
In addition to BRCA1 and BRCA2, other genes such as CDH1, PTEN, TP53 and STK11 are also linked to an increased risk for breast cancer. Genetic testing—which involves a blood sample and DNA analysis— is offered to those who, based on personal or family health history, are likely to have an inherited mutation. Testing isn’t routinely performed on women at average risk.
Hereditary cancer clues
If you’re concerned about your risk for breast cancer, the first step is to collect your family’s health history.
Investigate both your mom’s and dad’s side of the family tree, and write down which relatives have had cancer, what type of cancer and the age at which they were diagnosed. Also include their ethnicity and which side of the family they’re on.
You may be at increased risk of hereditary breast cancer if your family history includes one or more of the following:
- Several relatives with either breast or ovarian cancer.
- Breast cancer at a young age (under 50).
- A relative with cancer of both breasts.
- A relative who has had both breast and ovarian cancer.
- A male relative with breast cancer.
- Ashkenazi Jewish ancestry in any relative with breast or ovarian cancer.
- A relative with a known BRCA1 or BRCA2 genetic change.
If any of these apply to someone in your family, bring your concerns to a health care provider or genetic counselor. She or he can help assess your risk, evaluate your options and guide you in whatever direction is right for you.
Options for Women at High Risk
Women with a strong family history of breast cancer and women who carry a harmful mutation in the BRCA1 or BRCA2 genes are at an increased risk of developing breast cancer.
Women who fall into these high-risk categories are often advised to begin screening for breast cancer earlier and undergo more frequent screening. However, screening only serves to catch cancer early when it’s most treatable — it doesn’t lower the risk of breast cancer.
For those women who fall into a high-risk category, they may opt to take more aggressive preventive measures in order to reduce their risk of developing the disease. There are several options to consider, such as the use of anti-estrogen therapy, and the preventive removal of the breasts and/or ovaries.
Choosing aggressive preventive measures is an extremely personal decision. If you’re at high-risk for developing breast cancer, it’s crucial that you discuss your options with a health care provider who can help you make the most informed decisions.
Anti-estrogen therapy refers to the use of drugs to block the effects of estrogen. This is the least invasive approach to prevention—but only serves a certain subset of women. Anti-estrogen therapy can reduce the risk of developing estrogen-receptor positive breast cancer.
There are currently two drugs that are FDA-approved for breast cancer prevention: tamoxifen and Evista® (raloxifene).
- Tamoxifen is approved for breast cancer risk reduction in women who are at high risk of the disease (including high-risk premenopausal women).
- Evista — originally approved for the prevention and treatment of osteoporosis — is approved for breast cancer risk reduction in postmenopausal women with osteoporosis or postmenopausal women at high risk of breast cancer.
Both drugs are taken orally. Tamoxifen is more effective than Evista in reducing breast cancer risk; however, Evista has been shown to have fewer harmful side effects than tamoxifen.
Bilateral Prophylactic Mastectomy (Preventive removal of both breasts)
Bilateral prophylactic mastectomy refers to the removal of both breasts to prevent breast cancer. Women at high risk of breast cancer may reduce their risk of developing breast cancer by 90 percent by undergoing bilateral prophylactic mastectomy.
Prophylactic mastectomy is a drastic measure that may decrease emotional stress regarding the concern over developing breast cancer; however, it may also increase stress related with self-esteem, sexuality and femininity.
Some high-risk women choose this approach because it helps ease their worries about developing breast cancer. While this procedure can greatly decrease the risk of developing cancer, it is not a guarantee that cancer will not develop. Because a mastectomy does not remove all of a woman’s breast tissue, there is always a small chance that breast cancer could occur in the remaining tissue.
Women considering this procedure need to weigh the benefits against the consequences, which include the irreversibility of the procedure, the psychological impact and potential problems with implants and reconstructive surgery. The benefits of the procedure appear to be the greatest in younger women.
Prophylactic Oophorectomy (Preventive removal of the ovaries)
Prophylactic oophorectomy refers to preventive removal of the ovaries. The BRCA1 and BRCA2 genes increase the risk of both breast and ovarian cancer. Prophylactic oophorectomy is one option for reducing this risk—for both ovarian and breast cancer since some breast cancers grow as a result of hormones produced by the ovaries. The procedure lowers the risk of breast cancer by 40 to 70 percent and the risk of ovarian cancer by 70 to 90 percent.
Surgery doesn’t completely eliminate risk because some cells remain behind after surgery. Women with a BRCA1 or BRCA2 alteration who have had their ovaries removed have about half the risk of developing breast cancer as those who have not had their ovaries removed.
Adverse effects of prophylactic oophorectomy include the inability to have children and the development of menopausal symptoms such as hot flashes.
- American Cancer Society. Cancer Facts & Figures 2013.
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- Collaborative Group on Hormonal Factors in Breast Cancer. Breast cancer and breastfeeding: collaborative reanalysis of individual data from 47 epidemiological studies in 30 countries, including 50302 women with breast cancer and 96973 women without the disease. Lancet. 2002;360:187-195.
- Manson JE, Chlebowski RT, Stefanick ML, et al. Menopausal hormone therapy and health outcomes during the intervention and extended poststopping phases of the Women’s Health Initiative randomized trials. JAMA. 2013;310:1353-1368.
- Moorman PG, Havrilesky LJ, Gierisch JM, et al. Oral contraceptives and risk of ovarian cancer and breast cancer among high-risk women: a systematic review and meta-analysis. Journal of Clinical Oncology. 2013;31:4188-4198.
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- Reeves GK, Kan SW, Key T, et al. Breast cancer risk in relation to abortion: Results from the EPIC study. Int J Cancer. 2006;119:1741-1745.
- Committee on Gynecologic Practice. ACOG Committee Opinion No. 434: induced abortion and breast cancer risk. Obstetrics and Gynecology. 2009;113:1417-1418.
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- National Cancer Institute. FactSheet: Antiperspirants/Deodorants and Breast Cancer. Available at: http://www.cancer.gov/cancertopics/factsheet/Risk/AP-Deo. Accessed January 15, 2014.
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- Domchek SM, Friebel TM, Singer CF, et al. Association of risk-reducing surgery in BRCA1 or BRCA2 mutation carriers with cancer risk and mortality. JAMA. 2010; 304(9):967-975.
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