What is the secret to longevity?

Researchers think they may have found the answer to the age-old question in a handful of remote villages in southern Italy where several hundred citizens aged 90 or over live.

A new study, published in the journal International Psychogeriatrics, has identified common psychological traits among this group which could explain their extended lifespans.

The researchers found that the older participants - who were aged between 90 and 101 - had better mental well-being than their younger family members – aged between 51 and 75 - despite their poorer physical health.

Previous research examining people who live long lives has tended to focus on the impact of genetics. In contrast, the new study looks at the role of mental health and personality.

"The main themes that emerged from our study, and appear to be the unique features associated with better mental health of this rural population, were positivity, work ethic, stubbornness and a strong bond with family, religion and land," said Dilip V. Jeste from the University of California San Diego.

For the study, 29 participants from nine villages in the Cilento region of southern Italy were assessed for a range of physical and personality traits, and were also asked personal questions about their own lives relating to topics such as migrations, traumatic events and beliefs.

The children or other younger family members of this group were also assessed and were asked to describe their impressions of their older relatives' personalities.

"The group's love of their land is a common theme and gives them a purpose in life," said Anna Scelzo from the Sapienza University of Rome. "Most of them are still working in their homes and on the land. They think, 'This is my life and I'm not going to give it up.'"

The researchers also found that the participants had considerable self-confidence and decision-making skills, supporting the 'paradox of ageing' theory – the notion that well-being and wisdom increase with age, despite failing physical health.

One participant described to the researchers how he dealt with painful experiences in life.

"I lost my beloved wife only a month ago and I am very sad for this. But thanks to my sons, I am now recovering and feeling much better. I have fought all my life and I am always ready for changes. I think changes bring life and give chances to grow."

Another spoke about how optimism was a key component to how he approached every day.

"I am always thinking for the best. There is always a solution in life. This is what my father has taught me: to always face difficulties and hope for the best."

Yet another stressed the importance of keeping busy.

"I am always active. I do not know what stress is. Life is what it is and must be faced... always."

The authors noted that the participants tended to be domineering, stubborn and reported a need to be in control. This can be a desirable trait as it means they are "true to their convictions and care less about what others think", according to Scelzo.

"This tendency to control the environment suggests notable grit that is balanced by a need to adapt to changing circumstances."