This paper examines the effect of life expectancy on economic growth, using the international epidemiological transition as an empirical strategy. The transition, which began in the 1940s, led to significant improvements in life expectancy, particularly in poorer countries, due to global health interventions, better public health measures, and new medical treatments. The authors construct an instrument for changes in life expectancy based on pre-intervention disease mortality rates and global intervention dates. They find that predicted mortality has a large and robust effect on changes in life expectancy starting in 1940, but no effect before. Instrumented changes in life expectancy have a large effect on population, with a 1% increase in life expectancy leading to a 1.5% increase in population. However, life expectancy has a much smaller effect on total GDP, both initially and over a 40-year horizon. The results suggest that the large exogenous increase in life expectancy did not lead to a significant increase in per capita economic growth. These findings confirm that global efforts to combat poor health conditions in less developed countries can be highly effective, but also cast doubt on claims that unfavorable health conditions are the root cause of poverty in some nations. The paper also discusses the role of changes in capital-labor ratios and the importance of investment rates in determining the effects of life expectancy on economic growth. The authors find that improved health has been a great benefit to less-developed nations during the postwar era, but that global efforts to improve health conditions may not necessarily lead to significant long-term increases in income per capita. The paper also notes that the effects of health improvements may differ depending on the type of disease and the specific context in which they occur. The authors conclude that while health improvements can have positive effects on individual productivity and economic outcomes, they may not necessarily lead to significant increases in overall economic growth.This paper examines the effect of life expectancy on economic growth, using the international epidemiological transition as an empirical strategy. The transition, which began in the 1940s, led to significant improvements in life expectancy, particularly in poorer countries, due to global health interventions, better public health measures, and new medical treatments. The authors construct an instrument for changes in life expectancy based on pre-intervention disease mortality rates and global intervention dates. They find that predicted mortality has a large and robust effect on changes in life expectancy starting in 1940, but no effect before. Instrumented changes in life expectancy have a large effect on population, with a 1% increase in life expectancy leading to a 1.5% increase in population. However, life expectancy has a much smaller effect on total GDP, both initially and over a 40-year horizon. The results suggest that the large exogenous increase in life expectancy did not lead to a significant increase in per capita economic growth. These findings confirm that global efforts to combat poor health conditions in less developed countries can be highly effective, but also cast doubt on claims that unfavorable health conditions are the root cause of poverty in some nations. The paper also discusses the role of changes in capital-labor ratios and the importance of investment rates in determining the effects of life expectancy on economic growth. The authors find that improved health has been a great benefit to less-developed nations during the postwar era, but that global efforts to improve health conditions may not necessarily lead to significant long-term increases in income per capita. The paper also notes that the effects of health improvements may differ depending on the type of disease and the specific context in which they occur. The authors conclude that while health improvements can have positive effects on individual productivity and economic outcomes, they may not necessarily lead to significant increases in overall economic growth.