Risk Factors for Breast Cancer

Risk factors for developing breast cancer are made up of two categories – preventable and non-preventable. Studies have shown that about 5% to 10% of breast cancers in women can be attributed to non-preventable reasons, such as hereditary genes. Conversely, approximately 30% of diagnosed breast cancers are likely caused from environmental risk factors.

Non-Preventable Risk Factors

  • Age – As much as modern science is trying to prevent it; we cannot turn back the hands of time. Like many diseases, the risk of developing breast cancer increases with age. Current research indicates that women in their 60s are 100 times more likely to develop breast cancer than women in their 20s.
  • Gender – Men can develop breast cancer; however, the risk is much less than for women. According to the American Cancer Society, breast cancer kills almost 40,000 women annually compared to about 390 men.
  • Heredity – Gene defects, known as mutations, can be inherited from your parents. These mutations are known as BRCA1 and BRCA2. Women, who inherit these mutations, have an increased risk of about 60% to 80% of developing breast cancer. Genetic testing for BRCA1 and BRCA2 genes is available to women with a family history of breast cancer.
  • Family History – Women with a direct family history of breast cancer have double the risk of developing breast cancer than women with no direct family history. A direct family history is defined as a first degree relative – mother, daughter, or sister.
  • Ethnicity – Caucasian women have a greater risk of breast cancer than African American, Hispanic, Asian and Native-American women; however, African American women are more likely to die from breast cancer
  • Dense Breast Tissue – Recent studies have shown that women with dense breast tissue have an increased risk for breast cancer.
  • Breast Lesions – Some non-cancerous breast conditions have been linked to breast cancer. Some examples include: fat necrosis, cysts, ductal ectasia, phyllodes tumor and adenosis (See Non-Cancerous Breast Condition Section).

Preventable Risk Factors

  • Diet – There has been conflicting results from research conducted regarding fat intake and breast cancer. However, several studies have shown that breast cancer is less prevalent in countries where low-fat diets are common.
  • Obesity – According to a recent study published by the Cancer Institute, obese women have an increased risk of developing breast cancer. The theory behind this research is that excessive fat tissue in the body raises estrogen levels. It is this increased level of estrogen that creates exposure to breast cancer.
  • Birth Control – Women who take oral contraceptive have a slight risk of breast cancer. Some studies have indicated that women who take birth control pills before the age of 20 are at an increased risk of breast cancer.
  • Hormone Replacement Therapy (HRT) – During menopause, some women take hormones, such as estrogen and progesterone to help relieve symptoms. During a randomized controlled trial (sampling where an “experimental group” receives treatment and a “controlled group” who doesn’t receive treatment are studied) evidence revealed potential hazards of hormone therapy. According to that, study, known as the Women’s Health Initiative Study which was released 10 years ago the women who took hormones were at a greater risk of developing breast cancer. However, a recently released new study, the Kronos Early Estrogen Prevention Study, known as KEEPS reported in the Oct. 3, 20112 issue of the LA Times that “Healthy middle-aged women who take hormones to ease the misery of hot flashes and night sweats have fewer depressive symptoms, less anxiety and tension, and better and more sex than those who do not.”  It was further reported that, ‘Though the long-term effects of hormone replacement therapy could not be measured by the new research, it did offer some reassuring findings. It suggested that some women’s cholesterol profiles and metabolic function might improve on hormone replacement therapy and that blood pressure did not rise during or after a relatively brief stay on hormone replacement.” In view of these new finding, women are advised to discuss all the benefits and risks of HRT options that are open to them  with their health care providers
  • Alcohol – According to the American Cancer Society, women who consume one alcoholic drink daily are at a moderate risk for developing breast cancer. On the other hand, women, who drink 2 to 5 drinks, have a 1.5% chance of developing breast cancer. It has been shown that alcohol consumption raises estrogen levels; therefore, increasing a women’s risk factor for breast cancer.
  • Smoking – According to the California Environmental Protection Agency, smoking can increase a woman’s chance for breast cancer. Studies published by the United States Surgeon General’s Office have also shown links to breast cancer from secondhand smoke.