Investment in Health: Social and Economic Returns Scientific and Technical Publication No. 582. Washington, D.C.: Pan American Health Organization; 2001. 292 pp. Price: US$32.00/US$24.00. ISBN 92 75 11582 6. The relationship between health and the economy has been recognized for decades, and remains a key concern for health system designers. The chain of effects from health investments to economic growth, human productivity, and poverty reduction is becoming more solid. Health is a key factor for economic growth, more so than education. Good health increases income by boosting education, productivity, and individual participation, especially for women. However, good health can also increase fertility in lower and middle socio-economic strata, reducing income and schooling. The decision to work or stay at home due to motherhood is also important. Higher economic growth leads to higher population growth, a long-term effect that must be considered. When benefits do not reach the poor, income polarization occurs, neutralizing the benefits of increased health investment. Good information systems are essential for evaluating costs, benefits, and effects. New health technologies can generate long-term benefits with relatively low costs. It is necessary to analyze the effects of different types of subsidies on population health. From an economic perspective, the two fundamental components of human capital are health and education. Research from Colombia highlights the relationship between health status and personal income. Each additional day of illness reduces the income of a farmer by 32% and a woman by 13%. A centimeter additional height increases the income of an urban worker by 8% and a woman by 7%. Disability in rural areas is mainly due to the lack of social security services. In urban areas, higher social security levels are associated with more work-related disabilities. The type of housing and availability of public services have a clear influence on personal income and health status. A second protocol, generated in Mexico, examined the relationship between health, nutrition, and salaries, using the income of adult women and the age of menarche as indicators. Results show that the age of menarche has been decreasing in Mexico over the last 40-50 years, due to urbanization, increased education, and improved living conditions, including access to public services and better housing. In contrast, the availability of health services has a marginal impact on the age of menarche. A third protocol, conducted in Peru, analyzed the relationship between health and income by gender and region. Findings confirm that health is a component of human capital that influences salary levels and, therefore, an individual's ability to sustainably increase income over time. This has immediate consequences for purchasing power and family living standards. Section 3 of the work discusses the relationship between the level of investment in health services and the reduction of poverty levels. It describes 1Investment in Health: Social and Economic Returns Scientific and Technical Publication No. 582. Washington, D.C.: Pan American Health Organization; 2001. 292 pp. Price: US$32.00/US$24.00. ISBN 92 75 11582 6. The relationship between health and the economy has been recognized for decades, and remains a key concern for health system designers. The chain of effects from health investments to economic growth, human productivity, and poverty reduction is becoming more solid. Health is a key factor for economic growth, more so than education. Good health increases income by boosting education, productivity, and individual participation, especially for women. However, good health can also increase fertility in lower and middle socio-economic strata, reducing income and schooling. The decision to work or stay at home due to motherhood is also important. Higher economic growth leads to higher population growth, a long-term effect that must be considered. When benefits do not reach the poor, income polarization occurs, neutralizing the benefits of increased health investment. Good information systems are essential for evaluating costs, benefits, and effects. New health technologies can generate long-term benefits with relatively low costs. It is necessary to analyze the effects of different types of subsidies on population health. From an economic perspective, the two fundamental components of human capital are health and education. Research from Colombia highlights the relationship between health status and personal income. Each additional day of illness reduces the income of a farmer by 32% and a woman by 13%. A centimeter additional height increases the income of an urban worker by 8% and a woman by 7%. Disability in rural areas is mainly due to the lack of social security services. In urban areas, higher social security levels are associated with more work-related disabilities. The type of housing and availability of public services have a clear influence on personal income and health status. A second protocol, generated in Mexico, examined the relationship between health, nutrition, and salaries, using the income of adult women and the age of menarche as indicators. Results show that the age of menarche has been decreasing in Mexico over the last 40-50 years, due to urbanization, increased education, and improved living conditions, including access to public services and better housing. In contrast, the availability of health services has a marginal impact on the age of menarche. A third protocol, conducted in Peru, analyzed the relationship between health and income by gender and region. Findings confirm that health is a component of human capital that influences salary levels and, therefore, an individual's ability to sustainably increase income over time. This has immediate consequences for purchasing power and family living standards. Section 3 of the work discusses the relationship between the level of investment in health services and the reduction of poverty levels. It describes 1