The results are in!  Moderate physical activity, such as walking, can substantially reduce a woman’s risk of developing breast cancer.  Recent results of a large long-term study by the American Cancer Society support a strong correlation between physical activity and postmenopausal breast cancer risk.  Scientists have been collecting evidence for some time that exercise reduces the risk of many types of cancer; the question is, how much exercise is enough?

Over a 17 year study of 73,615 women, researchers found that just an hour a day of moderate physical activity – such as walking – reduced risk of breast cancer in postmenopausal women by 14%.  That’s not all: more vigorous activity was linked with a 25% lower risk of breast cancer compared with those who exercised 3 or fewer hours per week.

Current health guidelines for adults recommend at least 150 minutes, or 2 ½ hours per week, of moderate intensity exercise.  Less that half of U.S. women currently achieve these minimum activity levels.  Yet surveys indicate that more than 60% of women report walking daily.  By increasing this leisure-time activity to an hour a day, post-menopausal women can measurably reduce their breast cancer risk compared with those who exercise 3 or fewer hours per week.

Post-menopausal women are the age group most likely to develop breast cancer.   Approximately one out of every eight women in the U.S. will develop malignant breast cancer in her lifetime, and the risk increases with age.  Although a person can be diagnosed with breast cancer at any age, 2 out of 3 invasive breast cancers are found in women aged 55 and older.

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For more information about breast cancer signs, symptoms and treatment options, visit the National Breast Cancer Awareness Month website, the American Cancer Society, Mayo Clinic, and Susan G. Komen For the Cure.