The Role of Food, Fitness, and Weight in Your Risk of Breast Cancer
Each year, we learn more about how a woman's lifestyle and health habits -- the kind of food she eats, how much she weighs, the amount she exercises -- can affect her risk of developing breast cancer. American Cancer Society experts Colleen Doyle, MS, RD, director of nutrition and physical activity, and Heather Spencer Feigelson, PhD, MPH, strategic director of genetic epidemiology, discuss the latest research.
Q: For women who want to lower their risk of breast cancer, is there any benefit to watching what you eat, controlling your body weight, and getting regular physical activity?
Feigelson: Absolutely. We know that being overweight can increase the risk of breast cancer after menopause. And that risk increases with weight gain. Women who gain more than 70 pounds as adults double their risk. Physical activity has been associated with a 10%-25% reduction in risk. Maintaining a healthy weight, being physically active, and reducing alcohol intake are the best ways for women to reduce their risk of breast cancer.
Of course, all women age 40 and older need to be getting yearly mammograms to uncover any sign of breast cancer as early as possible, when treatments are most successful.
Q: Are there specific foods, eating plans, or calorie levels that you recommend for women who want to lower their risk of breast cancer? What about a low-fat diet?
Doyle: There are no specific foods a woman should eat to reduce breast cancer risk. For women who are concerned about their risk of breast cancer, the best eating plan (and calorie level) is one that helps them achieve a healthy weight.
Q: What about alcohol consumption? How much is too much?
RESOURCES:
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Q: Most Americans are overweight. At what point does being overweight start to increase a woman's risk for breast cancer? Should women be concerned if they gain 15-25 pounds of "middle-aged spread" as they age?
Feigelson: Breast cancer risk begins to increase when adult weight gain (defined as weight gain since age 18) is more than 20 pounds. A recent American Cancer Society Study found that women who gained 21-30 pounds since age 18 were 40% more likely to develop breast cancer than women who had not gained more than 5 pounds, and women who gained 70 pounds doubled their risk.
Further, excess weight greatly increases the risk for metastatic tumors, which are more difficult to treat than tumors that have not spread. Women who gained more than 60 pounds since age 18 were 3 times more likely to have metastatic breast cancer than women who gained less than 20 pounds as an adult.
Q: Will losing weight reduce my risk of breast cancer?
Doyle: Recent studies do show that losing weight can help lower the risk of post-menopausal breast cancer. The key message for women is it's really never too late to start living healthier.
Q: What about physical activity? How much is needed to lower breast cancer risk? What kinds of activities count?
Doyle: Physical activity affects breast cancer in 2 distinct ways: directly, by influencing circulating hormones, and indirectly, by helping to control weight. The American Cancer Society recommends that women be moderately to vigorously active for 45-60 minutes on 5 or more days per week to lower breast cancer risk.
Activities considered moderate are those that make you breathe as hard as you would during a brisk walk. This includes things like walking, biking, and even housework and gardening. Vigorous activities generally engage large muscle groups and cause a noticeable increase in heart rate, breathing depth and frequency, and sweating.
Q: Can you describe a typical daily or weekly exercise schedule for a woman who wants to lower her risk for breast cancer?
Doyle: Each woman can determine how to fit 45-60 minutes of activity into her day, 5 days a week, by finding the things that she really enjoys doing and will keep doing. A few pointers that may help women design their own plan are:
- Strive to make it a priority. Schedule physical activity into your day/week just like other appointments you have.
- Exercise with others. Many women find it easier to stay motivated and committed if they are exercising with other people. If you are that type, find someone who shares your desire to get more activity.
- If lack of childcare is an issue, maybe you could find someone in your neighborhood who could "switch off" with you -- you watch her kids while she works out, and she watches yours when you work out.
