Lowering Risk for Breast Cancer

Breast cancer is the most common cancer among women, next to cancer of the skin. While it strikes older women most often, 10,000 women under 40 will also learn they have breast cancer this year. A woman's chance of having the disease over her entire lifetime is 1 in 7, and there are slightly more than 2 million in this country who've been treated for the disease. But there's some good news too. First, more of these women are outliving their diagnosis of breast cancer. And, though there's no foolproof way to prevent this cancer, we are learning more about how to reduce our risk for developing it

Breast cancer risk rises with age, and is higher among those who have a family history of the disease, had their first child later in life, started menstrual periods before age 12 or stopped having them after 50. Though it's good to be aware of these and other risk factors, many of them are beyond our control. But there are positive steps we can take.

Get Moving. Breast cancer risk is greater for mature women who are very overweight. Researchers aren't certain why that's so, but one theory focuses on estrogen production in overweight women. Even when a woman's ovaries stop making estrogen after menopause, fat cells keep producing it. Scientists believe that long term exposure of breast cells to this hormone contributes to risk. An active lifestyle helps prevent excess body fat, which, in turn, helps a woman produce less estrogen.

What about younger women? Well study results just in report that weight loss of about 10 lbs. reduces risk in overweight women between the ages of 18-30 who are genetically susceptible to breast cancer due to a mutation in the BRCA1, but not BRCA2 gene (1). Too much weight around the midsection can also lead to chronically elevated levels of the hormone insulin-another potential cancer-contributing culprit. So keeping weight down is the right strategy, and increasing physical activity along with cutting calories is the way to go about it.

The American Cancer Society suggests 30 minutes of moderate exercise such as walking, dancing or leisurely biking, at least 5 days a week. Recent research has shown that even simple activities like walking for half an hour daily can also improve a woman's chances of surviving breast cancer (2).

Limit Alcohol. Alcohol raises risk, and limiting alcoholic beverages may increase the liver's ability to regulate estrogen levels. But doesn't that regular glass of wine or spirits help protect against heart disease? Yes, but it's a matter of trade-offs. One healthy compromise may be to keep alcohol intake down to a glass several times a week. If you've had breast cancer, though, check with your doctor for guidance.

Eat well. Researchers are still trying to solve the diet and breast cancer puzzle. However, a diet that's generally low in fat and high in fruits, vegetables and whole grains may confer some protection. UCLA researchers recently reported that women eating this way and exercising may lower their risk of developing this cancer (3). Additionally, a low fat regimen combined with standard treatment reduced recurrence in older women diagnosed with breast cancer (4). Intensely colored fruits and veggies are full of fiber, vitamins and other compounds with cancer-fighting actions. Dark greens like spinach for instance, are rich in folic acid, which may lower risk, particularly in alcohol consumers. Vitamin C and beta-carotene, found in citrus and red or orange-colored produce may also be risk-reducing.

Finally, take advantage of the National Cancer Institute's website (www.nci.nih.gov) to learn how to do a monthly breast self-exam and see the latest mammogram guidelines. Early detection along with weight control, staying active, eating well and using alcohol sensibly is a good strategy for strengthening our defenses against breast cancer.

References

1. Kostsopoulos J, et al. Changes in body weight and the risk of breast cancer in BRCA1 and BRCA2 mutation carriers. Breast Cancer Res 7:R833-43, 2005.
   
2. Holmes MD, et al. Physical activity and survival after breast cancer diagnosis. JAMA 293:2479-86, 2005.
   
3. Bernard J, et al. Presented at the International Research Conference on Food, Nutrition and Cancer, Washington, DC, July 2005.
   
4. Chlebowski RT, et al. Dietary fat reduction in postmenopausal women with primary breast cancer: phase III Women's Intervention Nutrition Study (WINS). Proc Am Soc Clin Oncol. 23:3s. Abstract 10, 2005.