weight and diet, exercise regularly, keep alcohol consumption at low to moderate levels, and get screening tests for cancer that have proven effectiveness. Doing so could shift the balance away from the current devotion of attention and resources to the treatment of advanced disease to more effective prevention (Woolf, 1999).
In this chapter, the National Cancer Policy Board summarizes the evidence presented in the report to address four questions:
What lifestyle and health care behaviors contribute to the burden of cancer?
What share of new cases of cancer and cancer deaths could be prevented with changes in lifestyle and health care behavior?
What interventions work to bring about health-enhancing behavioral change?
What steps can be taken to overcome barriers to using effective interventions and to improve what we know about cancer prevention and early detection?
The Board recognized that a number of personal and health care behaviors are known to contribute to the burden of cancer but limited its review to tobacco use, obesity, physical activity, diet, alcohol use, and the use of screening tests. Examples of behaviors known to contribute to cancer risk but not considered in this report, include exposure to sun and exposure to cancer-causing viruses through sexual activity (e.g., human papillomavirus) and blood contact such as through intravenous drug use (e.g., hepatitis B virus).
Tobacco is responsible for approximately 30 percent of cancer deaths in the United States, an estimated 170,000 deaths in 2002 (ACS, 2002a). A causal link between smoking and lung and laryngeal cancer was first made public in the 1964 Surgeon General’s report, Smoking and Health (U.S. Department of Health Education and Welfare, 1964). Since then convincing evidence has accumulated to support smoking as a cause of several cancers including cancers of the oral cavity, esophagus, bladder, kidney, pancreas, cervix, colon, and stomach, and leukemia.
Smoking increases the risk of lung cancer 10- to 20-fold and the risk of other cancers up to 5-fold, depending on an individual’s smoking habits and history. Although the lung cancer risk in former smokers never quite returns to that for individuals who have never smoked, it is drastically