The study behind the claim

A study by professors at the University of Sassari and the University of Alabama at Birmingham, published in Frontiers in Aging last week, calculated that 13.8% of women in Bolotana who reach the age of 70 will live to 100 - a figure that places the village second in the world for female longevity after Hong Kong.

The finding could put the village, population 2,266, in the running to become the world's sixth blue zone, an area with an unusually high concentration of centenarians. Sardinia was home to the first such zone, identified more than 25 years ago.

The groundwork was laid by Tore Pedde, president of the cultural association Orminas, who uncovered Bolotana as a longevity hotspot by painstakingly searching its demographic archives, even tracking down centenarians born in the village who had long since moved overseas.

The archives told a striking story:

• Records of people born in Bolotana between 1900 and 1925 showed 38 lived beyond 100, a longevity rate 57% higher than the Italian national average.
• Until the early 1900s men outnumbered women among the village's elderly, but from the early 20th century women began to outnumber men, and female centenarians now far exceed males, according to Pedde.

The centenarians of Bolotana

At the head of the list are two sisters. Giovanna Marras is 101 and her sister Mariangela is 99, and both live in Bolotana. Giovanna is the third eldest of six female centenarians in the village, after Tonia Giglio and Maddalena Falchi, both 102.

More are on the way: two more Bolotana women are expected to turn 100 by the end of this year, and two more in 2027, including Mariangela. The village's last male centenarian, Giovanni Madau, died in July, a few months short of his 102nd birthday.

The sisters ran a tailoring business together. Giovanna had excelled at school before moving to Cagliari, the capital of the Italian island, at 18 to train as a seamstress, and the pair later travelled the world. Neither married. Giovanna recalled refusing a marriage proposal, telling her parents to send the suitor away. "I told them to tell him to go away – I mean, a woman should at least know her future husband."

Mariangela had her own reasons for staying single. "I didn't want to get married … I walk my own path, I don't need support," she said.

Not far behind them is Filomena Scarpa, a former language teacher who turned 100 in January. She began learning German in her 90s and was a voracious reader before a problem with her left eye slowed her down. "It saddens me not to be able to read with the same level of consistency," she said.

What could explain it

Giovanni Mario Pes, who led the study and co-created the blue zone concept, said the discovery marks a first for longevity research. "For the first time we've identified an area where women live to a great age," he said, noting that the original Sardinian blue zone was predominantly male.

The scientists behind the study are tracing family trees in search of genetic clues to Bolotana's female longevity, while also exploring diet, physical activity and social connections. That women tend to live longer than men for biological reasons is already established.

The village itself may help. Bolotana sits in Sardinia's Marghine mountains, about 70 miles (110km) from the island's original blue zone of villages. Pes said it is relatively close to cities including Sassari and Alghero on the west coast, but its streets are steep, providing residents with unavoidable exercise, the environment is unspoiled and most people eat garden-grown fruit and vegetables.

The centenarians' daily habits fit that picture. The Marras sisters still cook for themselves, eating a varied but clean diet without forsaking meat, cheese or wine, and Mariangela does the shopping - a walk down a hilly street and back. Scarpa goes to a personal trainer twice a week. "Because I can't sit around all day," she said.

Pes has also noticed something social. He noted a strong sense of sisterhood among Bolotana's female residents. "This felt quite unusual and is something I'd like to explore scientifically," he said.

How the village cares for its elderly

The mayor of Bolotana, Francesco Manconi, believes sociality is key, citing an abundance of natural affection towards the elderly from family, neighbours and friends. The village also places great importance on ensuring elderly residents can stay in their own homes, he added.

Betti Uda, who runs a tourism business in the village, said the elderly women are determined and live purposefully. "If they want to do something, they will – nothing holds them back," she said.

The bonds run deep. Scarpa, who has two sons, is a childhood friend of Maddalena Falchi, who now lives with her daughter about an hour away in Oristana; the pair speak often. Falchi is notorious in Bolotana for heavy smoking, and Scarpa said she told her to quit - to which Falchi replied: "It hasn't got me so far, so I shall carry on."