September 29, 2013 | by Hiu Chung So
As with most types of cancer, the risk of developing breast cancer is based on both genetic and environmental factors. The former is fixed, but people do have control over the latter. The key is to make lifestyle choices that can lower that risk.
Establishing precisely what those choices are — and their impact — is the goal of Leslie Bernstein, Ph.D., R.N., professor and director of City of Hope's Division of Cancer Etiology. Bernstein is also the principal investigator of the California Teachers Study, which has tracked more than 133,000 participants since 1995 to assess whether certain behaviors are linked to cancer and other diseases later in life.
In the video above, Bernstein talks about two actions women can take to minimize their cancer risk: Exercise regularly and limit alcohol intake.
"People always say, 'Is it the activity or the fact that it makes you thinner?' and we think it's the activity directly, so I always recommend that women exercise," Bernstein said.
The advice holds true regardless of women's weight. Her published studies linked exercise to lower odds of developing breast cancer in both normal weight and overweight women.
Bernstein added that, although research hasn't yet established what type or intensity of exercise yields the most benefit, the reduction in breast cancer risk was observed in women who exercised at least three to four hours per week.
Alcohol intake plays another significant, if minor, role in breast cancer risk.
"If you drank one alcoholic drink a day, your risk would only increase minutely, by 10 percent. And that's small," Bernstein said, suggesting that women who choose to drink alcohol should limit their consumption to no more than one alcoholic beverage a day.
Bernstein and her team are now looking into the role of regular aspirin intake on breast cancer risk, because aspirin acts against inflammation and aromatase — both of which are linked to breast cancer growth and development.
Further, the California Teachers Study is starting to collect blood and saliva samples from its participants, so researchers can better study the gene-environment interactions and other factors that lead to breast cancer.
There is no one lifestyle choice that can prevent breast cancer, but Bernstein strongly urges women to start or continue a regular exercise regimen. Not only does it lower cancer risk, it can also add years to your life.