The Blue Zones: areas of exceptional longevity around the world

The aim of this study was to compare the level of population longevity and
the characteristics of four geographic areas where unusually high proportions of
long-lived individuals have been observed. For these areas (Ogliastra in Sardinia,
Okinawa in Japan, the Nicoya peninsula in Costa Rica and the island of Ikaria
in Greece). The term of ‘blue zone’ (BZ) given to these areas is defined as a
limited region where the population shares a common lifestyle and environment
and whose exceptional longevity has been accurately verified. This paper discusses
the use of different indexes to measure the longevity of a population. As a
preliminary result of our investigations we confirm the exceptional level of
male longevity in the Sardinian BZ and both male and female longevity in
Okinawa. Considering possible explanations, we observed that BZ populations
are geographically and/or historically isolated (islands and mountainous regions).
These populations succeeded in maintaining a traditional lifestyle implying an
intense physical activity that extends beyond the age of 80, a reduced level of
stress and intensive family and community support for their oldest olds as well
as the consumption of locally produced food. This is likely to have facilitated the
accumulation of ideal conditions capable of limiting the factors that negatively
impact on health in most Western populations. These people experienced the
epidemiological transition—and its implications—in relative recent times, and their
remarkably good health status during ageing could be the result of a delicate balance
between the benefits of the traditional lifestyle and those of modernity (increased
wealth, better medical care). All these factors could have promoted an ideal milieu
for the emergence of long-lived phenotypes at the population level.