folate and colorectal cancer), but further research is needed to confirm these specific associations.
A downward shift in the population distribution of alcohol intake could lead to decreases in the incidence of cancer and injuries, but it could also lead to higher rates of cardiovascular disease because consumption of moderate amounts of alcohol confers some protection against cardiovascular disease. Public education campaigns must focus on reductions in hazardous drinking and encouraging those who choose to drink to do so moderately.
A core consensus has emerged about the appropriateness of some methods of cancer screening. There is essentially universal agreement across organizations that all adults age 50 and older should be screened for colorectal cancer, that all women should receive mammograms every 1 to 2 years beginning at least by age 50, and that cervical cancer screening should occur regularly in all sexually active women with a cervix. Appropriate use of screening could reduce the rate of mortality from colorectal cancer by 30 to 80 percent (among adults age 50 and older), reduce the rate of mortality from breast cancer by 25 to 30 percent (among women age 50 and older), and reduce the rate of mortality from cervical cancer by 20 to 60 percent (among women age 18 and older).
Projections of the precise number of cancer cases and cancer deaths that could be averted with changes in individuals’ health behaviors are difficult to make, but recent estimates suggest that if current trends toward a decline in the prevalence of cancer risk factors continue over the next decade, by the year 2015 one could expect a 13 percent decline in cancer incidence rates and a 21 percent decline in cancer mortality rates below those in 1990. With redoubled efforts to reduce the prevalence of known cancer risk factors further, by the year 2015, cancer incidence rates could be reduced by 19 percent and cancer mortality rates could be reduced by 29 percent. Such redoubled efforts would equate to the prevention of approximately 100,000 cancer cases and 60,000 cancer deaths each year by the year 2015 (Byers et al., 1999).
More than half of the estimated future gains are attributable to projected reductions in tobacco use. Although it is difficult to predict the future