What is the relationship between physical activity and risk of endometrial cancer?
About 20 studies have examined the role of physical activity on endometrial cancer risk. The results suggest an inverse relationship between physical activity and endometrial cancer incidence. These studies suggest that women who are physically active have a 20 percent to 40 percent reduced risk of endometrial cancer (6), with the greatest reduction in risk among those with the highest levels of physical activity. Risk does not appear to vary by age (4). Changes in body mass and changes in the levels and metabolism of sex hormones, such as estrogen, are the major biological mechanisms thought to explain the association between physical activity and endometrial cancer. However, fewer than half of the studies in this area have also adjusted for the potential effect of postmenopausal hormone use, which may increase the risk of endometrial cancer. A few studies have examined whether the effect of physical activity varies according to the weight of the woman, but the results have been incon
