Probably helpful to realize that the lifespan is determined more than just one metric, such as healthcare. Cultural differences between different regions likely plays a significant effect. For instance, my guess is diet leading to obesity helps to drag down life expectancy in the regions where the life expectancy is lower:
Not just cultural differences. Things like car accidents and murders also play a disproportionate role.
If nation A has 60 people living to 79, and nation B has 59 people living to 80 and 1 person being murdered at 20, A and B have the same mean life expectancy (of 79).
Though I suppose you could call things like murders and road safety "cultural".
http://www.cdc.gov/obesity/data/animated_map_slides/map26.jp...