We all know that exercise is good for your heart, but did you know that it also decreases your risk of breast cancer?
As a breast surgical oncologist, I am often asked by patients if there is anything they can do to lower their risk of developing breast cancer. Along with a healthy diet and lifestyle choices, regular exercise is one of the best things women can do to keep the risk of a first-time breast cancer or recurrence as low as it can be.
Studies have shown that patients who are physically active can achieve up to a 50 percent lower risk of breast cancer compared to sedentary patients (1). Exercise has also been shown to decrease the risk of breast cancer recurrence in women who have already been treated for cancer (2). As a result, the American Cancer Society recommends that women who have been diagnosed with breast cancer, as well as those who haven’t, exercise regularly.
More research is being done to determine how exercise decreases the risk of breast cancer, but the current theory is that the female hormone estrogen plays a key role. Higher estrogen levels in the blood place women at an increased risk for developing breast cancer and physical activity helps regulate these hormones, which can fuel breast cancer growth (3). Additionally, exercise boosts the immune system, aiding the body in being able to fight off disease and potentially target and kill cancer cells, or slow their growth.
While the exact amount of exercise needed to decrease the risk of breast cancer is still being investigated, studies have shown that any amount of exercise is better than none.
Also, more vigorous activity is more effective than less vigorous activity. “Regular exercise” is defined as about four to five hours per week at a moderate intensity level. Examples of moderate intensity activities include brisk walking, dancing, practicing yoga, golfing, gardening, and leisurely bike riding. Jogging, basketball, tennis, soccer, and swimming are considered more vigorous exercise routines. Interestingly, if women stopped exercising, the risk-reducing benefits have been shown to quickly disappear.
Finding time to exercise on a daily basis can be difficult. One technique you can try is to break up exercise into 20- or 30-minute sessions that add up to about four hours per week.
Walking is a great way to start, even if it is only a short session on your lunch break. Also, exercising with a friend will help you be accountable to keep up this healthy habit and will allow you to socialize at the same time.
If there is a topic you would like to hear more about pertaining to women’s health or more specifically breast health, you can message me on Facebook @drstarrmautner.
1. Thune I, Brenn T, Lund E, Gaard M, Physical activity and the risk of breast cancer. N Engl J Med. 336:1269-1275, 1997.
2. Lahart IM, Metsios GS, Nevill AM, Carmichael AR. Physical activity, risk of death and recurrence in breast cancer survivors: A systematic review and meta-analysis of epidemiological studies. Acta Oncol. 54(5):635-54, 2015.
3. Schmitz KH, Williams NI, Kontos D, et al. Dose-response effects of aerobic exercise on estrogen among women at high risk for breast cancer: a randomized controlled trial. Breast Cancer Res Treat. 154(2):309-18, 2015.