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The Ecology of Breast Cancer

The promise of prevention and the hope for healing

By The Science and Environmental Health Network

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The Ecology of Breast Cancer: the promise of prevention and the hope for healing makes the case that breast cancer is a disease arising from diverse societal conditions. Although well-recognized risk factors and a person’s life style are important, they simply do not explain why many people develop breast cancer. Nor do they fully explain breast cancer patterns in populations.

The author, Ted Schettler MD, MPH, is Science Director of the Science and Environmental Health Network. He also serves as Science Director of the Collaborative on Health and the Environment. Schettler reviews and analyzes an extensive literature addressing known, probable, and plausible risk factors for developing breast cancer as well as its recurrence and progression after diagnosis and treatment. He concludes that interactions among features woven into the fabric of our lives and communities collectively create conditions that make breast cancer more or less likely. Thinking about this as an ecological challenge, he argues, helps us identify multi-level interventions that will reduce breast cancer risk and improve outcomes after diagnosis.

“In many ways, breast cancer is a design problem”, Schettler concludes. “It is not only a disease of abnormal cells but also of communities that we create and live in. Breast cancer is profoundly a public health concern, requiring a public health response.”

Preventing breast cancer and reducing recurrences requires measures that confront the systemic roots of the disease. The agriculture and food system, many aspects of the built environment, and pervasive hazardous chemicals all play a role. These cannot be addressed by individuals alone. Community planners, health care professionals, public health officials, businesses, schools, governments, and farmers also have opportunities to help reduce the burden of this disease.

The book briefly discusses well-recognized risk factors for breast cancer, including family history, personal history of breast cancer, genetic susceptibility, early puberty, late menopause, late age of first child or having no children, dense breast tissue, chest irradiation, current use of oral contraceptives, combination hormone therapy, cigarette smoking, and alcohol consumption. It goes on to explore what we know about other variables and emphasizes the importance of taking a life course approach, beginning with fetal development. Extensive evidence shows that breast biology and later risk of breast cancer in adults are influenced by conditions experienced during fetal development, infancy, childhood, and adolescence. Among the conclusions:

  • Healthy pregnancies are essential. That means healthy nutrition, appropriate exercise, optimal maternal vitamin status including vitamin D, and avoiding exposures to chemicals and other environmental agents that may alter fetal development, increasing the risk of cancer and other diseases in childhood and years later.
  • Infants should be exclusively breast fed if possible for at least six months and given a vitamin D supplement as recommended by the American Academy of Pediatrics. Vitamin D supplementation may be necessary throughout life to achieve optimal but not excessive serum levels.
  • Healthy food is essential throughout life. Growing evidence shows that unhealthy childhood and adolescent diets are strongly linked to adverse health outcomes in adulthood, including breast cancer. Ready access to sources of healthy, affordable food is a high priority. It influences what people actually eat.
  • Throughout infancy, childhood, adolescence, and adulthood efforts should be undertaken to reduce or eliminate exposures to environmental chemicals and contaminants that can alter breast development or otherwise damage breast tissue. Consumer product reformulation, eliminating chemicals plausibly linked to breast cancer, will reduce exposures. Exposure to mammary gland carcinogens in the workplace can be reduced by using safer substitutes and improved worker protection.
  • Regular exercise lowers breast cancer risk and is essential for the health of children, adolescents, and adults. But physical activity levels are not just a matter of personal choice. Land use and transportation planning, availability of parks and recreation facilities, and school policies strongly influence peoples’ physical activity levels.
  • Avoid unnecessary exposure to both ionizing (e.g., X-rays, CT scans) and non-ionizing radiation, as from cell phones carried close to the body.
  • Stress reduction as part of a comprehensive integrated approach to breast cancer care and treatment improves quality of life for most people and reduces the risk of recurrence in some.