Eat more beans
Soy foods have grabbed the headlines, but “phytoestrogens also abound in most other beans,” says botanist James Duke, Ph.D., author of The Green Pharmacy. Dr. Duke recommends enjoying a bean soup, or bean salad, or low-fat Mexican fare with pinto or black beans a few times a week. 
Cut down on — or cut out — alcohol
Many studies show that as alcohol consumption increases, so does the risk of breast cancer.  Most recently, in a report in the Journal of the American Medical Association, Harvard researchers analyzed six long-term studies of alcohol and breast cancer risk involving more than 322,000 women. As the women’s alcohol consumption increased, so did their breast cancer risk. One drink a day raised risk only slightly (9%), but two to five drinks a day raised it 41%.  Alcohol raises blood levels of estrogen. 
Watch your weight
Every pound you gain after age 18 increases your risk of breast cancer, according to a recent analysis by Harvard researchers of data from the Nurse’s Health Study, an ongoing study tracking the diet, lifestyle, and health of more than 95,000 female nurses. Compared with nurses who gained only five pounds since age 18, those who were 45 pounds heavier had twice the breast cancer risk. As body fat increases, so do blood levels of estrogen, the hormone that promotes breast tumor growth. 
Steer clear of xenoestrogens
Xeno” means “foreign,” that is, from outside the body. Women ingest xenoestrogens from primarily two sources: the residues in meats of estrogenic hormones given to food animals, and the residues of estrogenic pesticides on produce. The role of xenoestrogens in breast cancer risk remains controversial, but mounting evidence suggests that xenoestrogens may increase blood estrogen levels enough to up the risk of developing breast cancer. Most recently, Danish researchers tested pesticide levels in the blood of 240 women with breast cancer and 477 women who were cancer-free. As blood levels of the xenoestrogenic pesticide dieldrin increased, so did the women’s breast cancer risk.  Dieldrin is banned in the United States, but other xenoestrogenic pesticides used here have also been linked to an increased breast cancer risk. 
The best ways to avoid xenoestrogens are to limit the consumption of meat, poultry, and whole-milk dairy foods, or shop for organic, hormone-free meats and dairy, and organic produce. But don’t let fear of pesticide residues deter you from eating lots of fruits and vegetables, adds Dr. Block of U.C. Berkeley. The benefits of their antioxidants and fiber outweigh any risk from pesticide residues.
Get some sun
Rising rates of malignant melanoma skin cancer threaten to turn us into a nation of sun-phones. But a little sun can help prevent breast cancer. Studies by epidemiologists Cedric and Frank Garland of the University of California at San Diego show that compared with women who live in northern latitudes, those who live in sunnier southern climes have a lower risk of breast cancer. When sunlight strikes the skin, the Garlands explain, the body makes vitamin D. This vitamin helps breast tissue absorb calcium, which in turn, reduces breast-cancer risk. The Garland brothers advise getting about 20 minutes of sun a day (just don’t get sunburned). A good way to do this is to take a walk at lunch or in the late afternoon.  If you are concerned about not getting enough calcium or vitamin D from food or sunlight, you may want to try supplements. The Daily Value (DV) for vitamin D is 400 international units. The DV for calcium is 1,000 milligrams.
As if you need another reason not to smoke, a study by Christine Ambrosone at the University of Buffalo shows that smoking increases breast cancer risk, with the greatest increase in women who started smoking as teens and those who smoke more than a pack a day. 
Breastfeed your babies
For reasons that remain unclear, breastfeeding is associated with a modest reduction in developing breast cancer before menopause. The longer a woman breastfeeds, the greater the benefit. 
Think twice before taking hormone replacement therapy (HRT).
There are several good reasons to take HRT after menopause: lower risk of heart disease, osteoporosis, and Alzheimer’s disease. But HRT increases breast cancer risk. Talk with your doctor, and weigh your individual risks of all these conditions as you become menopausal. Most women are at higher risk for heart disease than they are for breast cancer. 
Finally, one more pointer to possibly trim your risk:
The medical literature hints that stress might increase breast cancer risk. Stress depresses immune function, so a biological case can be made for stress increasing risk of just about every disease.  But the research on the alleged stress-breast cancer link is very controversial, and the studies showing an association are currently scant and outweighed by studies to the contrary. Nonetheless, it’s a good idea to incorporate a stress management regimen into your life — meditation, yoga, tai chi, gardening, or other relaxing activities.
Bottom line advice: Don’t get stressed-out about your breast cancer risk. Do something about it.
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18 Author survey.
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22 Duke, J. The Green Pharmacy. Emmaus, PA: Rodale Press, 1997, p. 16.
23 “Alcohol Use Reportedly Increases Breast Cancer Risk,” Medical Tribune 5-22-97. “Even Modest Alcohol Intake Raises Risk of Breast Tumors,” Medical Tribune 7-13-95.
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