Housework may be a hated chore but it can reduce the risk of a certain form of uterine cancer, U.S. and Chinese researchers reported on Monday.
And a second study showed that patients with breast cancer who exercised regularly were more likely to survive.
The reports, presented at the annual meeting of the American Association for Cancer Research in Orlando, Florida, strengthen other findings that show exercise lowers the risk of several forms of cancer, as well as heart disease and diabetes.
“Exercise in adulthood was associated with nearly a 20 percent reduction in endometrial cancer risk,” a team led by Charles Matthews of the Vanderbilt University Medical Center in Nashville, Tennessee, told the meeting.
“Our results support the idea that the risk of cancer can be reduced by maintaining an active lifestyle,” Matthews added in a statement.
Matthews and colleagues at the Shanghai Cancer Institute in China found that walking and household chores reduced the risk of endometrial cancer by as much as 40 percent.
They studied 974 women in Shanghai aged 30 to 69 and compared them to women of a similar age. The women were asked about current exercise as well as how much they exercised as teen-agers.
Women who walked more than 60 minutes a day and who did four or more hours of housework a day had a 30 percent lower risk of endometrial cancer -- a cancer of the lining of the uterus.
“In recent years, we have accumulated strong evidence that an active lifestyle can reduce the risk of colon and breast cancer. Now we are finding that physical activity may also reduce risk of endometrial cancer,” Matthews said.
Offsetting too much body fat
Having too much body fat can increase the risk of endometrial cancer but Matthews said exercise may counter some of this risk.
Matthews’ team did a second study in Shanghai on breast cancer but found the effects were less clear.
They surveyed 1,459 breast cancer patients and 1,556 women without breast cancer.
The heavier women were always at higher risk. As with endometrial cancer, exercise seemed to offset some of the increased risk caused by being fat.
“At this juncture, obesity prevention offers one of the few viable options for breast cancer prevention,” the researchers said.
A second team, at Brigham and Women’s Hospital and Harvard University, showed that exercise increased the survival of women with breast cancer.
“We already knew that exercise improves the quality of life after a breast cancer diagnosis,” Dr. Michelle Holmes, who led the study, said in a statement.
They studied 2,296 breast cancer patients taking part in a large health study of nurses, following them from 1986 until they died or until June 2002.
The more the women exercised, the better their chances of beating the breast cancer.
Women who walked an hour a week or did the equivalent were 19 percent less likely to die and women who managed three hours a week were 54 percent less likely to die of breast cancer.
But the benefits dropped off -- more exercise than that did not result in better survival.
“We were able to show that even a moderate amount of physical activity improved the odds of surviving breast cancer,” Holmes said.
“It is especially heartening for women recovering from breast cancer to know that the benefit is as readily accessible as walking for 30 minutes on most days of the week.”