How to Prevent Breast Cancer: 20 Risk Factors

What causes breast cancer? Anyone who has been diagnosed with the disease, or watched a friend or family member have to deal with it, wants to know. Research has taught us that many widely understood risk factors play a role, including our genetic makeup and whether or not we've had kids or breast-fed. But these risk factors don't explain it all. A substantial body of scientific evidence indicates that exposures to common chemicals and radiation, alone and in combination, may contribute to the unacceptably high incidence of breast cancer.

Not only are exposures to particular chemicals and mixtures important, but the timing of these exposures may be critical. Breast tissue is developing from prenatal stages through the time that a woman gives birth and breastfeeds, and breast structures that have not gone through the full sequence of development are particularly sensitive to the detrimental effects of environmental toxins. The cancer usually doesn’t show up until adulthood, but the stage may well have been set in the womb, or early in childhood.

What can we do? This feature will help you identify some known and suspected breast cancer risk factors. Some of these tips apply mostly to middle aged or older adults – both women and men – who are at the age when diagnosis is most common. Other tips will help parents protect their children, even in the womb.

Janet Gray is the director of the Environmental Risks and Breast Cancer project at Vassar College, in Poughkeepsie, N.Y. and a board member of the Breast Cancer Fund. The Environmental Risks and Breast Cancer project is designed to communicate known and suspected environmental triggers for breast cancer to the general public.