A new study shows exercise may help decrease the risk of breast cancer in postmenopausal women.
Researchers from the Fred Hutchinson Cancer Research Center studied more than 74,000 women who were between ages 50 and 79 years old. The women were assessed according to their level of physical activity, which was based on how many hours per week they exercised. The level of activity the women had at ages 18, 35 and 50 years was also considered. Researchers documented cases of breast cancer in this group for nearly five years to determine if a lack of physical activity is linked to the disease.
Results of the study show women who engaged in regular strenuous physical activity at age 35 had a 14-percent reduced risk of breast cancer. Similar findings were also reported in women who engaged in strenuous physical activity at ages 18 and 50. High total current physical activity scores were also associated with a reduced risk of breast cancer. The effect of exercise was most evident in women with the lowest body weight.
Researchers say the results are encouraging, but older women should not feel they need to overexert themselves. Authors of the study write, "The finding that increased total recreational and walking physical activity reduces this risk is promising, although it may not be necessary for women to engage in strenuous activity in their older years to enjoy the protective effects of exercise."
Another positive finding from the study is that physical activity reduced the risk of breast cancer in women who were using hormone therapy. Previous studies have shown women who take hormone therapy are at a higher risk for breast cancer.