date relations between investments in health, economic growth, and household productivity (WHO, 1999). Estimates based on data from Mexico throw some light on the time frame in which health affects economic indicators. High life expectancy at birth for males and females has an economic impact 0-5 years later. The impact of male life expectancy on the economy appears to be greater than that of female life expectancy, possibly because of the higher level of economic activity among males. The data suggest that for each additional year of life expectancy there will be an additional 1 percent increase in gross domestic product 15 years later. Similar findings were found for schooling.
Studies of this kind are in their infancy compared to other studies described in this report. Much remains to be done to link macro-level associations to the community and individual-level dynamics as discussed in Chapter 2, Chapter 3, Chapter 5, and Chapter 6. Understanding the reciprocal relationships between population health and the macroeconomy and their linkages to micro-level behavioral dynamics and intermediate-level community and social structural influences is a high-priority research direction. Indeed, it is precisely results such as those for Mexico, described above, that have implications for national economic policies leading to sustained commitments to investments in health. Providing clear evidence about linkages to community and individual levels can substantially strengthen the arguments for national commitments.
Health and the economy have long been linked by the practice of having children to ensure being cared for in old age. This is still true in many countries, but with public-sector innovations such as Social Security and medical care, the direct need for children as insurance has declined. In its place are issues of individual behavior (whether people live alone or with their children, whether they work or retire) and social questions about whether society can afford to provide care to an aging population.
The backdrop for much of the concern about changes in health is the strain that increasing length of life places on public programs in industrialized countries. The Social Security system in the United States is forecast to become insolvent around 2030, and Medicare is expected to be insolvent long before then. This situation, repeated throughout the developed world and in many developing countries, is made worse as population growth rates fall. Health improvements have hidden costs if they lead to difficulty financing public-sector programs for the elderly. However, recent evidence of rectangularization of survival curves, not only for mortality but for the age-specific onset of disability and chronic diseases (Vita et al., 1998), suggests that prevention strategies may be having positive countervailing effects.
Health improvements can play a substantial role in solving public-sector problems. People who develop a serious illness late in their working