Two million . residents die each year; it is estimated that half of these deaths are "premature" and attributable to lifestyle and environmental factors (UC Berkley Wellness Letter 1997). Advances in biomedical sciences, mass immunization, and sanitation have resulted in a decrease in the incidence of infectious diseases (Matarazzo 1984), so that the health status of the population in economically developed countries now has less to do with acute illness than with lifestyle issues such as excessive drinking, unhealthy diet, or the use of tobacco products (Walsh et ). Influencing lifestyle can do more to increase the health of the population and lower the cost of health care than can.
