Women who get regular physical activity may have a lower risk of breast cancer [141-143]. Although not all studies have shown this benefit, when the evidence is looked at as a whole, regular exercise appears to lower breast cancer risk by about 20 percent [144]. This is seen most clearly in postmenopausal women [145].
Physical activity can also help with weight control. For postmenopausal women, being lean lowers the risk of breast cancer [113-115]. And, physical activity may lower estrogen levels in women, which can also protect against breast cancer [43,146]. Low to moderate levels of physical activity may also boost the body’s immune system so that it can help kill or slow the growth rate of cancer cells [147].
Learn more about body weight and breast cancer risk.
Learn more about estrogen levels and breast cancer risk.
Physical activity can delay the first period until an older age and reduce the frequency of regular menstrual cycles. Each of these can help decrease the total amount of estrogen a woman is exposed to over her lifetime [42].
Physical activity and breast cancer survival after treatment
Whether or not regular physical activity after diagnosis may also protect against breast cancer recurrence is under study. Early studies suggest that regular exercise after diagnosis increases overall survival among breast cancer survivors [148,149]. And, it has other health benefits. Regular exercise can increase positive mood and improve physical condition and movement, which can in turn, enhance quality of life [150,151].
Updated 11/09/09
