Last article we looked at several factors that increased a woman’s risk of developing breast cancer but could not be changed. The purpose of this was to encourage women at increased risk to receive screening measures beyond those developed for women at average risk. Today we’ll look at a number of factors that increase the risk of developing breast cancer, but in some cases can be modified to reduce that risk.

• Drinking alcohol— Some studies have found that women who have two to three alcoholic drinks per day have a 20 percent higher risk of breast cancer than non-drinkers.
• Being overweight or obese— Before menopause, when the ovaries are producing estrogen, being overweight or obese slightly decreases breast cancer risk. After menopause the ovaries stop making estrogen and most of a woman’s estrogen comes from fat tissue. With excess fat related to obesity, estrogen production increases along with breast cancer risk. Women who are overweight tend to have higher blood insulin levels also which is thought to increase breast cancer risk.
• Physical inactivity— Getting regular exercise appears to reduce the risk of developing breast cancer.  In one study from the Women’s Health Initiative, as little as 1¼ to 2½ hours per week of brisk walking reduced a woman’s risk by 18%.
• Having children— Women who have not had children or who had their first child after age 30 have a slightly higher breast cancer risk overall. Having many pregnancies and becoming pregnant at an early age reduces breast cancer risk overall.
• Taking birth control pills— Some studies have found that women using oral contraceptives (birth control pills) have a slightly greater risk of breast cancer than women who have never used them. This increased risk is thought to go away after being off of oral contraceptives for 10 years.
• Receiving hormone therapy after menopause—- Hormone therapy with estrogen or with a combination of estrogen and progesterone is used to help relieve symptoms of menopause and to help prevent osteoporosis. Estrogen therapy alone is typically used in a post-menopausal woman who has had her uterus removed (hysterectomy). In post-menopausal women who still have a uterus, the combination of estrogen and progesterone was typically used. The use of estrogen alone after menopause does not appear to increase the risk of developing breast cancer. Estrogen plus progesterone increases the risk of both developing and dying from breast cancer.
• Breastfeeding—- Research shows mothers who breastfeed for at least 6 months lower their risk of pre- and post-menopausal breast cancer.

In contrast to last week’s list of risk factors for the development of breast cancer, several of the risk factors mentioned this week provide an opportunity to be modified in order to bring down one’s risk of developing breast cancer.

Last week, the new breast cancer screening recommendations from the American Cancer Society for women at average risk were presented. These deserve mentioning a second time to encourage every woman to discuss their risks for developing breast cancer and to undergo appropriate screening.

1. Women with an average risk of breast cancer – most women – should begin yearly mammograms at age 45.
2. Women should be able to start the screening as early as age 40, if they want to. It’s a good idea to start talking to your health care provider at age 40 about when you should begin screening.
3. At age 55, women should have mammograms every other year – though women who want to keep having yearly mammograms should be able to do so.
4. Regular mammograms should continue for as long as a woman is in good health.
5. Breast exams, either from a medical provider or self-exams, are no longer recommended.

Sources for article:
Breast Cancer Prevention and Early Detection from the American Cancer Society
What Affects Your Chances of Getting Breast Cancer from Susan G. Komen

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