Healthier and Wealthier
The Volokh Conspiracy on the correlations between health and wealth in a region, a connection with compelling evidence both before and after the Industrial Revolution: "for most of history, gains in human life expectancy were made at the beginning, not the end of life. It is true that older people have always been part of society, but they were less numerous and more weathered than today's seniors. ... But that is not the end of the story. Rather, it is the beginning of a new chapter where humanity takes on ill health and death at later ages. Indeed, those efforts have already had an impact on the growth of life expectancy. ... For many years, it's been clear that there is a positive correlation between health and wealth, but it was most commonly thought that wealth creates health. While it is certainly true that the rich can afford to take better care of themselves, it is now known that health also begets wealth. Put another way, poor health causes a decline in productivity for the simple reason that it's very difficult to work effectively when you're in ill health, thereby increasing the chances of falling into poverty. ... based on the available research, if there are 'two countries that are identical in all respects, except that one has a 5 year advantage in life expectancy,' then the 'real income per capita in the healthier country will grow 0.3-0.5% per year faster than in its less healthy counterpart.' While these percentages might look small, they are actually quite significant, especially when one considers that between the years of 1965 to 1990, countries experienced an average per capita income growth of 2% per year. When countries only have an average growth of 2%, an advantage of 0.5% is quite the boost. Now, those numbers are based only on a 5 year longevity advantage. What if a country had a 10, 20, or 30 year advantage? The growth may not continue on a linear basis, but if the general rule holds - a jump in life expectancy causes an increase in economic growth per capita - then having a longer-lived population would facilitate enormous differences in economic prosperity."