One five-year window puts Bolotana women's odds of reaching 100 near four times Italy's

The ages hold up. Researchers worked through civil records and church archives of births, baptisms and deaths ^[17]. "The municipal and baptismal records date back centuries and allowed us to independently verify ages. Every single person that has made it past 100, we can validate. There is no ambiguity," said S. Jay Olshansky, a co-author and professor emeritus of epidemiology at the University of Illinois Chicago ^[7][20].

The same archive search produces a figure that does not depend on a five-year window. Discover reports 38 centenarians among 3,060 people born in the village between 1900 and 1925 ^[17]. That is about 1.24% of births ^[24]. The share pools men and women and counts every birth, including people who died young. The 13.83% figure is a probability for a woman already aged 70, built from 2021-2025 data ^[1], so the two numbers measure different things. Neither outlet gives an Italian cohort figure to set beside the village's.

The survival rate is less secure. The 13.83% estimate is about 3.9 times the Italian figure ^[23], and about 9.5 times the 1.46% the same analysis gave for 2015-2019 ^[22]. That earlier figure is below the national numbers quoted for Italy, 3.54% ^[2], and for the US, 3.6% ^[3]. Life expectancy at 70 moved much less, holding at 18.3 years in the earlier window and still above the Italian average ^[5].

Bolotana lies about 110 km west of the original Sardinian Blue Zone, identified roughly 20 years ago, according to ScienceAlert ^[12]. The mountain communities already on the blue zone list were known for an exceptionally high number of long-lived men ^[21]. "Females almost always live longer than males anywhere in the world, but in Sardinia that wasn't the case. It's one of the things that made it so unusual," Olshansky said ^[19]. "We think this is the longest-lived female population in the world, or close to it," he said ^[8]. In Bolotana, women's estimated odds of reaching 100 are about 2.8 times the men's ^[25].

The paper lists candidate causes. "Several mechanisms could plausibly contribute to the pronounced female survival advantage," the researchers wrote, "including genetic background, dietary patterns, physical activity, family support, social cohesion, continuity of residence, and access to care" ^[11]. Olshansky describes a steep, hilly town where most food is grown locally and social isolation is rare ^[14]. "You've got this close-knit community where people take care of each other," he said ^[14]. The thing this doesn't tell you is why those conditions would favour the village's women so much more than its men ^[15]. The analysis was demographic, and the authors put cause outside its scope ^[10].

I think Bolotana is worth using as a comparison population, because its ages can be checked ^[7]. I would treat 13.83% as one five-year reading until another window, or a cohort life table, comes out close to it ^[1][5].