Breast cancer is the disease many women fear the most.
While known primarily as a woman’s disease, men also develop breast cancer.
What is breast cancer?
Breast cancer occurs when cells in the breast divide and grow without their normal control. Sometimes, cancer cells can spread to nearby tissue or other parts of the body (invasive breast cancer).
What increases the risk of breast cancer?
Many factors are linked to breast cancer risk. Some factors affect risk a great deal and others by only a small amount. Some risk factors you can’t change. For example, the two most common risk factors for breast cancer, being a woman and getting older, are not things you can change. Other factors you may be able to control. For example, leading a healthy lifestyle may help lower your chances of getting breast cancer. Here are the most important factors that are linked to breast cancer (alphabetically ordered).
High breast density means there is a greater amount of breast and connective tissue compared to fat.
Low breast density means there is a greater amount of fat compared to breast and connective tissue.
Women with high breast density are more likely to get breast cancer than women with low breast density.
Having a first-degree relative (male or female) with breast cancer or a first-degree female relative with ovarian cancer increases the risk of breast cancer. Having a first-degree male relative with prostate cancer may also increase the risk of breast cancer.
Carotenoids are natural orange-red food pigments found in fruits and vegetables (like melons, carrots, sweet potatoes and squash). Beta-carotene is an example of a carotenoid.
Studies have found that women with higher blood levels of carotenoids have a reduced risk of breast cancer compared to women with lower levels.
Estrogen plus progestin increases the risk of both developing and dying from breast cancer.
Some studies have shown estrogen alone increases the risk of breast cancer. However, one large study found a decreased risk. (Estrogen alone is only used by women who have had a hysterectomy because it increases the risk of uterine cancer.)
MHT is not usually given to breast cancer survivors because it may increase the risk of recurrence.
Overweight and obesity affect risk for pre- and postmenopausal women differently.
Before menopause, being overweight or obese modestly decreases breast cancer risk.
After menopause, being overweight or obese increases breast cancer risk.
Gaining weight in adulthood appears to increase the risk of breast cancer (both before and after menopause).
Ductal carcinoma in situ (DCIS) is a non-invasive breast cancer. DCIS survivors have an increased risk of DCIS in the opposite breast as well as an increased risk of invasive cancer in either breast.
A personal history of Hodgkin’s disease, ovarian cancer and certain other cancers can also increase the risk of breast cancer.
Very low doses of radiation (such as from X-rays and other medical imaging) do not have much, if any, impact on breast cancer risk.