[swalling]

The other factor in Costa Rica is political stability and low military spending. After their civil war in 1949, they constitutionally abolished the military (Article 12) which not only prevents military juntas from emerging but also enables spending on healthcare in a low GDP country.

All that said, Blue Zones are fake, driven by cohort effects and poor record keeping. https://www.demographic-research.org/articles/volume/49/27/