Meet Your Calcium Quota
In May 2007, a study of 10,000 premenopausal women found that those who consumed 1,370 milligrams of calcium or more a day had a 40 percent lower risk for breast cancer than those who ingested 620 milligrams or less. And those who consumed a daily dose of at least 550 IU of vitamin D (which helps the body absorb calcium) had a 35 percent lower risk than those who consumed 160 IU. The vitamin intakes in the study were higher than current USDA recommended daily amounts (1,000 milligrams and 400 IU, respectively), so which number is right? "We will need to do a clinical trial to determine the optimum amount for breast health," says study author Jennifer Lin, PhD, assistant professor of medicine at Harvard Medical School. For now, hit the USDA quota, adding supplements if you can’t get it all from food. Even if it turns out that calcium doesn’t affect your breast cancer risk, you’ll make your bones stronger.
Choose the Right Technology
Typically, the breast tissue of premenopausal women is denser than younger women’s, which can make it more difficult to get a clear mammography image. "Because of that, there may be a small advantage for women at this age to get a digital mammogram rather than the traditional type," Saslow says. If your ob-gyn says you would benefit from this technology, the next step is to find a nearby center with the right equipment. This may be easy in urban areas and near teaching hospitals but harder in small cities and rural areas. One way to find locations is to check the equipment manufacturers’ Web sites: GE Healthcare (gehealthcare.com), Hologic (hologic.com), Siemens AG Medical Solutions (medical.siemens.com) and Fujifilm Medical Systems (fujimed.com). "If you don’t have access to a digital machine or if your insurance won’t cover it, you should still get an annual screening with a traditional machine," Saslow says. Pairing an ultrasound exam with a conventional mammogram is another option. Having both tests increased the number of tumor findings in women with dense breasts, according to a May 2008 study in the Journal of the American Medical Association. The downside: It also substantially upped the number of false positives (findings of something suspicious that later turned out to be normal).
Keep Hormones in Check
The more estrogen and progesterone your body is exposed to over your lifetime, the greater your risk for breast cancer. Hormone therapy and excess weight may increase your risk; breastfeeding, on the other hand, reduces it. But even if you take hormones and didn’t breastfeed (or never had children), there is still much that you can do to mitigate your risk. "Keep your weight steady, and get regular physical activity," advises Giske Ursin, MD, PhD, associate professor of preventive medicine at the University of Southern California. "Both have been shown to reduce hormone levels."