Last month, Brown University economist David Weil posted some thoughts about health and economic growth that summarized some recent findings in the subfield. Because improved population health can also increase population size, it isn't immediately clear that policies targeting health are really such a two-for-one kind of special, hopefully improving well-being and macroeconomic performance simultaneously. An article last year in The Economist summarized some of this research.
But Weil also points out that economists have measured the economic valuation of longevity gains themselves, completely separate from the value in increased incomes, as being extremely large. Even if health improvements didn't accelerate growth, they surely would bring enormous benefits on their own.