(NaturalNews) Recent research published in the journal Breast Cancer Research has found that vigorous activities, which include chores such as digging in the garden and heavy housework, lower the risk of women getting breast cancer. This protective effect, however, only applied to women who were in the normal weight range.
About Breast Cancer
In 2004, over 185,000 women and more than 1,800 men in the United States alone were diagnosed with breast cancer, while almost 41,000 women and 362 men succumbed to the disease.
In that year, breast cancer was the number two cancer killer of American women, ranked only after non-melanoma skin cancer, while also being their number five killer overall. In addition, for Hispanic women, breast cancer was the number one cancer killer.
In Canada, the picture isn't much better either. Among Canadian women, breast cancer is the most common form of cancer. The Canadian Cancer Society has estimated that some 22,400 women will be diagnosed with it this year, while about 5,300 will succumb to the disease.
Details of Study
Exercise has already been heavily linked with the prevention of many chronic diseases. Also, previously, other studies had suggested that women who went through more physical activity had lower risks of getting breast cancer. But this time, the researchers dug deeper.
In this study, conducted by the National Cancer Institute of the US National Institutes of Health, more than 32,000 women from across the United States were tracked for a period of 11 years. The average age of the subjects was 61, and all of them were free from chronic diseases at the start of the study. The participants were made to fill out a detailed questionnaire regarding their physical activity.
The survey asked the participants to estimate the typical number of hours which they spent each day carrying out various physical activities. These included moderate activities such as bowling, gardening, hiking, jogging lightly, mowing the lawn, vacuuming the floor and walking.
They also included vigorous activities such as aerobics, chopping wood, competitive tennis, cycling on hills, digging in the garden, fast dancing, heavy housework, heavy yard work, jogging quickly, running, scrubbing the floors and washing the windows.
Findings of Study
Overall, the participants of the study spent an average of 5.9 hours each day taking part in non-vigorous activities, and an average of 1.2 hours doing vigorous activities. By the end of 11 years, 1,506 of the women had been diagnosed with breast cancer.
The study found that the women who were the most active had a 13% lower risk of getting post-menopausal breast cancer, when compared with their least active counterparts.
A significant finding is that this difference was a lot more pronounced in women in the normal weight range (body mass index below 25). For this group, the difference in risk between the most active and least active women was 30%.
On the other hand, for women who were overweight or obese, there was no difference in risk between the most active and least active women.
"The association with physical activity was essentially limited to the leaner women," said Dr Michael Leitzmann, leader of the study.
One limitation of the study was that it only measured the level of physical activity once, which would not have given a very accurate reflection of the women's level of physical activity over the whole period of the study. Even then, the study team still felt that physical activity in mid to late adulthood had an important influence on the risk of breast cancer.
And, from the findings of the study, we can probably draw two conclusions. Firstly, even for women who are in the normal weight range, a sedentary lifestyle is still a risk factor for breast cancer. Further, for overweight women, being physically more active did not seem to help.
The bottomline? If you are serious about averting breast cancer, you may want to watch your weight, and make sure you are getting enough vigorous exercise.