Breast Cancer Risk Factors

Breast cancer risk factors are the things in your life that can increase your risk for getting breast cancer. Keep in mind that having a breast cancer risk factor, or even several, does NOT mean that you’ll get breast cancer. Studies are showing that most women with one or more of these factors are never diagnosed, while many women who ARE diagnosed have no apparent factors (aside from being female and growing older). Some factors have a greater influence than others and some will change over time due to aging and lifestyle.

The Breast Cancer Risk Factors You Cannot Change

• Gender (breast cancer is about 100 times more common among women)

• Age (breast cancer is about 4 times more likely in women over 50, than in their 40s)

• Genetics (Recent studies show about 5-10% of breast cancer cases are hereditary)

• Family history of breast cancer (especially if a mother or sister is diagnosed)

• Personal history of breast cancer (can develop a new cancer in the same or other breast)

• Race (white women are slightly more likely to develop breast cancer, but African-American women are more likely to die of it due to the fact they tend to have more aggressive tumors. Asian, Hispanic, and Native American women have a lower risk of developing and dying from breast cancer)

• Previous abnormal breast biopsy

• Atypical hyperplasia (A condition where there is an unusual increase in the number of normal cells in a tissue or organ…fibrocystic breasts)

• Previous breast radiation (especially if it was done in younger patients)

• Menstrual periods (started menstruating before age 12 or menopause after age 55)

• Diethylstilbestrol (DES) (given to some pregnant women in the 1940s through the 1960s because it was thought to lower their chances of losing the baby…recent studies have shown these women have a slightly increased risk of developing breast cancer)

Lifestyle Breast Cancer Risk Factors

• Not having children or having a first child after age 30 (increases risk)

• Oral contraceptive use (still uncertain – some studies show that use of oral contraceptives slightly increases risk - you should discuss this with your doctor)

• Breast-feeding (studies are mixed on whether this lowers the risk of breast cancer)

• Hormone Replacement Therapy (HRT) (long-term use after menopause increases risk)

• Alcohol (even 1 drink per day…risk increases with the amount consumed)

• Obesity & Diet (having more fat tissue can increase estrogen levels, thereby increasing risk)

• Physical activity (exercise reduces risk…as little as 1.25 to 2.5 hours per week of brisk walking)

Uncertain & Controversial Breast Cancer Risk Factors

• Antiperspirants (one small study found trace levels of antiperspirant preservatives in a small sample of breast cancer tumors, but didn’t look at whether that was the cause of the tumors. A larger study found no increase)

• Underwire bras (E-mail rumors and at least one book have suggested that bras cause breast cancer by obstructing lymph flow. There is no scientific or clinical basis for that claim)

• Induced abortion (According to one site, a recent report of 83,000 women with breast cancer found no link to a previous abortion, either spontaneous (stillbirth) or induced)

• Breast implants (Several studies have found that breast implants do not increase breast cancer risk, although they can cause scar tissue and make it more difficult to see breast tissue on standard mammograms)

• Environmental pollution (Lots of research is being done to understand environmental influences on breast cancer risk)

• Tobacco Smoke - Firsthand (Most studies have found no link between cigarette smoking and breast cancer. Some studies suggest it increased the risk)

• Tobacco Smoke - Secondhand (continues to be a focus of research. Both firsthand and secondhand smoke, in high concentrations, cause breast cancer in rodents)

• Night work (A few recent studies have suggested that women who work at night, for example, nurses on a night shift, have an increased risk of developing breast cancer. However, this increased risk has not yet been proven, and when further studies are conducted, this factor may be found to be unimportant)

Here are some links for more information and studies about breast cancer risk factors. Be sure to check out our Resource & Support pages too.

From the American Cancer Society

From Imaginis

Return from Breast Cancer Risk Factors to Support Groups

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