43 percent of people worldwide now live into their seventies, up from 33 percent twenty years ago. But just because we're living longer doesn't mean we're living better.

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PROBLEM: The world has changed in unfathomable ways since 1990, and one of the most salient ways of visualizing exactly how this is so is by looking at how -- and when -- we're dying now, compared to how we were dying then. Twenty years ago, the last time we took a step back to account for global patterns of this sort, the primary causes of death throughout the world were infectious disease and the consequences of childhood malnutrition. Many of the problems identified then have been addressed and, in some cases, solved by now. A critical look at the new challenges facing humanity, as a whole, can help us to refocus our health efforts for the 21st century.

METHODOLOGY: As befits a study of the entire world, this was a massive undertaking, with a lot of people analyzing a lot of data. The entire thing results from a collaboration of almost 500 researchers from 50 countries, led by the University of Washington.

RESULTS: Most children now make it to adulthood. Malnutrition has been cut by over 60 percent -- in a complete reversal from 1990, and with the exception of sub-Saharan Africa, kids generally have too much to eat. Poor diet and physical inactivity now contributes to 10 percent of the global disease burden.