The original Sardinian Blue Zone identified in 2000 was based on the spatial distribution of one thousand centenarians born between 1880 and 1900, according to their place of birth. It included 14 villages in Ogliastra and Barbagia, all located around La Marmora, the highest mountain in Sardinia. Since 2000, several thousand of new centenarians have lived in Sardinia and over 600 are alive today. Thus, it was important to re-examine the spatial distribution of longevity in Sardinia to confirm the existence of this Longevity Blue Zone and its evolution. This review of the Sardinian Blue Zone was carried out by M. Poulain with the support of ISTAT Roma and in collaboration with international experts from Belgium, France and Estonia as well as G. Caselli from La Sapienza University. 3000 centenarians born in Sardinia between 1907 and 1910 were distributed according their municipality of birth and these figures were divided by the corresponding number of new born of these municipalities. The probability of reaching 100 years of age was then mapped using a spatial smoothing method. The maps proposed here compare the new Blue Zone with the original one. Clearly, the Blue Zone has expanded out of Ogliastra to cover all the villages located to the West and South of La Marmora but expanding largely towards Cagliari. In addition, areas of high longevity are observed in the North of the island, in the Gallura, and in the South, around Teulada. Overall in Sardinia, the probability of becoming a centenarian has increased from 2 per thousand at the beginning of the century to 8 per thousand twenty years later. However, a person born in a village in the redefined Blue Zone has twice the chance to reach 100 compared with people born in the rest of Sardinia. In conclusion of this recent investigation, the mountainous area of Sardinia retains its Blue Zone status.
Longevity Blue Zones 