I'll bet you think the healthy Scandinavian countries are the balance of the top ten. Sorry, numbers 5, 9, and 10 are Japan, Australia, and Italy. These three are all serious nations, although only Japan has a partial reputation for healthy living.
What is there about tiny places that enables people to live longer? We don't know for certain, maybe they lie about their longevity? As King Mongkut said in The King and I, "It is a puzzlement."
A possible scenario: perhaps many tiny places don't have room or funds for retirement homes or fancy hospitals so these exist "across the border." Their elderly citizens may go across the border and die in the adjacent country, reducing the "at-home" death rate. I could believe that to be true of all the little places listed above except Singapore and to a lesser degree Hong Kong.
