Interesting. A little unrelated, but I've also noticed that many Arab countries have very low death rates (that is, natural death, not death by terrorism and such). The UAE has the lowest, and many of the lowest are all Middle Eastern countries. (
Source). I know dry desert air is good for curing tuberculosis, and I imagine that since viruses need wet and warm places to survive and that UV light destroys their genetic material, a desert would do them in.
(Notice that Iran and Iraq, which are not predominantly desert and have mountainous regions where it gets quite cold, are higher up on the list).
The reason is two fold: 1. Most Muslim nations have a large % of their populations in the 25 and under age-group: some are nearly 50% of their population.
2. The UAE, like the other gulf states have massive amounts of migrant populations (they outnumber the locals by 3 to 1 or more)
and that would explain the low natural death rate per 1000 inhabitants