According to Columbus gynecologist Dr. Otto Umana, researchers from the American Cancer Society have found that walking at least 7 hours each week is associated with an almost 15% lower risk of women developing breast cancer after menopause.
This finding is consistent with other studies that indicate that regular exercise can help women decrease their risk of breast cancer. New information in the study found that moderate exercise helped the women whether they were overweight or not, and helped them even if they gained weight while the study was ongoing.
Researchers reviewed breast cancer status and exercise levels in over 70,000 postmenopausal women taking part in the study that was initiated by the American Cancer Society in 1992. During the study, almost 4,800 of the women were diagnosed with breast cancer.
Among the women studied who reported walking as their only activity, those who walked a minimum of 7 hours per week had a 14% lower risk of breast cancer compared to those who walked less than 3 hours per week. The women walked at about 3 miles per hour, which is considered to be moderate. The most active women who walked and did more vigorous exercise enjoyed a 25% lower risk of breast cancer as compared to the least active group.
Your Columbus gynecologist Dr. Umana feels that the results visibly support a connection between physical activity and postmenopausal breast cancer, with more vigorous activity having a stronger effect. Without any other recreational physical activities, walking on average of at least one hour per day was correlated with a modestly lower risk of breast cancer, while more strenuous and longer activities lowered the risk even more.
Women in the study benefited from physical activity whether they were at a healthy weight, overweight, or obese, and even if they gained weight while the study was being conducted.
Exercise reduced the risk of estrogen receptor positive and estrogen receptor negative cancers. In estrogen receptor-positive breast cancer, estrogen promotes the growth of the cancer, and hormone therapy for breast cancer works by blocking the effects of estrogen or by lowering estrogen levels. Estrogen receptor-negative breast cancer is often harder to treat because it typically doesn’t respond to hormone therapy.
How exercising decreases breast cancer risk is still not fully understood, but researchers think that physical activity regulates hormones – including estrogen and insulin – that can fuel breast cancer growth.
If you have any questions regarding the effects of moderate activity on breast cancer risk, call your Columbus gynecologist Dr. Otto Umana’s office today!