Breast Cancer: Let’s Look at the Facts

Published October 20, 1995

October is National Breast Cancer Awareness Month, a time to learn more about the disease that strikes more than 180,000 women each year. Greater public awareness is an essential part of efforts to reduce the incidence and morbidity of this disease.

Unfortunately, some environmental groups have begun using this month to generate attention to their theories that air pollution, pesticides, or other man-made substances in the environment might cause breast cancer. Such theories are controversial within the scientific community and turn attention away from things we know with much greater certainty.

Here, briefly, is what we know, and don’t know, about breast cancer:

  • A number of conditions are associated with increased risk of breast cancer, including genetics, high-fat diets, having a first pregnancy late in life, and early onset of menstrual development. Other factors — such as environmental sources — have not been clearly tied to an increased risk of breast cancer.

  • Scientists have a long way to go before they can tell exactly what causes breast cancer. A recent commission appointed by the director of the National Cancer Institute to study breast cancer found that most of the studies conducted to date were “severely flawed methodologically or based on small samples.”

  • More women die of heart disease than from breast cancer or any other cause. Among cancer deaths, lung cancer has been the leading cause since 1987. Lung cancer now kills more women than any other cancer, and the incidence of lung cancer in women is on the rise.

  • Compared to their counterparts in the 1970s or before, women today are more likely to discover that they have breast cancer. Researchers believe this is largely because detection methods have improved and because women today are looking for the early stages of breast cancer, when treatment can be most effective. Changes in diet and lifestyle and an aging population may also be contributing to the rising incidence of breast cancer.

  • Women diagnosed with breast cancer have a better chance now of surviving. Between 1989 and 1992, the death rate for breast cancer in American women declined 4.7 percent — the largest such short-term decline in the United States for the disease since 1950.

Diane Carol Bast is publications director of The Heartland Institute, a nonprofit and nonpartisan center for public policy research located in Palatine, Illinois.