5. Be a "teatotaler." Antioxidant-rich green tea offers a potential triple threat against breast cancer, says Dr. Horner: It may decrease the production of estrogen, may help prevent the hormone from settling in the breast, and may shut off the blood supply to tumors. Some studies show that women who drink the most green tea have the lowest likelihood of getting the disease. If the preventive prescription of 6 to 10 cups daily sounds daunting, you can take a green tea extract supplement (available online or at health food stores). If you're brewing green tea, opt for an organic version to avoid pesticides.
6. Think twice about HRT. "It appears that taking combination hormone replacement therapy—estrogen and progesterone—for five years or longer is associated with a small but real increased risk of developing breast cancer," says Dr. Weiss. Women who have had a hysterectomy have the option of taking estrogen alone. That's a benefit, since a recent study found that while estrogen on its own does up women's risk, it takes 20 years to do so. Talk to your doctor to determine the best regimen for you; there are a variety of alternative ways to control menopausal symptoms, and other drugs that yield the bone-preserving benefits of estrogen.
7. Restrain yourself at happy hour. Research has identified a connection between alcohol consumption and breast cancer, probably because alcohol increases hormone levels. If you drink more than a modest amount (it's best to have five or fewer cocktails weekly) and also have low levels of folate, you may be particularly at risk, says Mary B. Daly, M.D., director of the family risk assessment program at Fox Chase Cancer Center in Philadelphia. Research shows that folate—a B vitamin found in beans, oranges, leafy vegetables, and enriched breads and cereals—helps to regulate normal DNA function. Damaged DNA is implicated in the start of cancer.