Olive Oil One Factor in Extraordinary Longevity of Some Sardinian Residents

The daily con­sump­tion of olive oil might have played a role in the extra­or­di­nary longevity of a small homo­ge­neous pop­u­la­tion on the Italian island of Sardinia, new research shows.

In one of the Longevity Blue Zones, areas where an unusual num­ber of peo­ple live excep­tion­ally long lives, spe­cific eat­ing habits cou­pled with exten­sive daily phys­i­cal activ­i­ties have out­run genet­ics as a longevity fac­tor.

“For a long time, researchers have been focus­ing on the genetic char­ac­ter­is­tics of this small pop­u­la­tion that lives in the moun­tain­ous area of cen­tral Sardinia, since demo­graph­ics showed us how their longevity and well-being data dif­fered from those observed in the other areas of the island, and Italy as well,” said Giovanni Pes, a pro­fes­sor of med­ical sci­ences at the University of Sassari, in Sardinia, and pri­mary author of the newly pub­lished study.

Initially, researchers focused on the his­tory of the island and its cen­turies-long iso­la­tion from the con­ti­nent, which has resulted in a homoge­nous and unique genetic her­itage. Still, those stud­ies did not help unravel the mys­tery.

“Our research, as well as many oth­ers, car­ried out here and else­where, hint at the fact that there is no direct cor­re­la­tion between genetic char­ac­ter­is­tics of the observed pop­u­la­tion and their longevity,” Pes told Olive Oil Times. ​“If we look at the most recent stud­ies about genet­ics and longevity, we under­stand how the genetic fac­tor does not exceed five or six per­cent in deter­min­ing the longevity of a pop­u­la­tion.”

Lifestyle, nutri­tion, phys­i­cal activ­ity and social bond­ing must have played a more sig­nif­i­cant role in deter­min­ing the Longevity Blue Zone char­ac­ter­is­tics than genet­ics, Pes argued.

Researchers inves­ti­gated those traits in a sam­ple of 150 of the island’s old­est res­i­dents, whose age ranged between 90 and 101 years.

“Participants were inter­viewed using val­i­dated ques­tion­naires to assess the con­sump­tion fre­quency of com­mon food items, and the cor­re­la­tion with self-rated health, comor­bid­ity, affec­tive and cog­ni­tive level, phys­i­cal mobil­ity, dis­abil­ity and anthro­po­met­ric para­me­ters,” Pes said.

The research inves­ti­gated how eat­ing habits changed over time in the inter­viewed sam­ple.

“We are talk­ing about a pop­u­la­tion who used to eat very sim­ply, gen­er­ally poor peo­ple who had access to what their land could offer, such as dairy prod­ucts derived from sheep and goats, with very lit­tle agri­cul­ture activ­i­ties tak­ing place on those steep hills,” Pes said. ​“They used to eat huge quan­ti­ties of bread baked out of cere­als imported from the plains, as well as legumes and pota­toes that were cul­ti­vated in small gar­dens.”

That pop­u­la­tion in the mid-20^th cen­tury ate mainly sat­u­rated ani­mal fats, such as lard, thus achiev­ing unusual longevity.

“We know that sat­u­rated fats are asso­ci­ated with a higher risk of car­dio­vas­cu­lar dis­ease,” Pes said. ​“At the time though that pop­u­la­tion was overly active every day.”

“In pre­vi­ous stud­ies, we have deter­mined a cor­re­la­tion between the ground incli­na­tion of the hills and the many miles they used to walk every day with their longevity,” he added. ​“Their energy con­sump­tion was sig­nif­i­cantly higher than that of the inhab­i­tants of the plains, and it has played a rel­e­vant role in let­ting them pre­serve their car­dio­vas­cu­lar fit­ness in older age.”

Researchers also believe that tra­di­tional fam­ily bonds have also played a role in the health of these excep­tion­ally old res­i­dents of the Longevity Blue Zone.

“Those are fam­i­lies who are used to liv­ing close together, one gen­er­a­tion after the other,” Pes said. ​“The old­est rel­a­tives live with the younger gen­er­a­tions. Emotional exchanges and dia­logue con­tribute to their men­tal health. The elders are very well respected by all here, unlike else­where.”

The intro­duc­tion of a more var­ied diet and the replace­ment of lard with olive oil brought fur­ther improve­ments, the researchers added.

“Our research focused on their food choices at younger ages, inves­ti­gat­ing their dietary his­tory,” Pes said. ​“While all lim­its on research based on the mem­ory of the inter­viewed sam­ple must be con­sid­ered, we believe that dur­ing their nutri­tion tran­si­tion, their eat­ing habits have improved because they ate sim­i­larly to the Mediterranean diet.”

Over the last few decades, olive oil pro­duc­tion has been expand­ing in Ogliastra, which sits at the heart of the Longevity Blue Zone. High-qual­ity extra vir­gin olive oil is now pro­duced and con­sumed by the local res­i­dents.

“Nutrition tran­si­tion is often con­sid­ered a neg­a­tive process involv­ing the switch from a healthy tra­di­tional diet rich in nutri­ents to a diet char­ac­ter­ized by exces­sive con­sump­tion of pro­teins, sat­u­rated fats and sim­ple sug­ars,” the researchers wrote in the study.

“However, in the Sardinian Longevity Blue Zone, the process also brought pos­i­tive ele­ments,” they added. ​“The tra­di­tional diet, con­tain­ing an unbal­anced intake of meat and dairy prod­ucts, was pro­gres­sively replaced by a diet more rep­re­sen­ta­tive of the typ­i­cal Mediterranean model, where the con­sump­tion of fish, leafy greens and fruit was higher.”

The research showed how the change in the diet habits across the nutri­tion tran­si­tion resulted in dif­fer­ent health and func­tional sta­tus out­comes.

“As expected, the analy­sis showed a ben­e­fi­cial health effect of the increased olive oil intake on self-per­ceived health, phys­i­cal per­for­mance and sense organs func­tion­al­ity,” the sci­en­tists wrote. ​“In addi­tion, a pos­i­tive asso­ci­a­tion was detected between an increased sheep, goat and chicken meat intake and func­tion­al­ity in activ­i­ties of daily liv­ing, sug­gest­ing that a sur­plus of ani­mal pro­teins may have indi­rectly improved motor per­for­mance by pre­serv­ing mus­cle mass.”

“Although meat con­sump­tion has been linked to increased all-cause mor­tal­ity, this is restricted to red and processed meat, while the con­sump­tion of poul­try meat, as in the case of Longevity Blue Zone, can pro­vide sev­eral health ben­e­fits,” they added. ​“The con­sump­tion of dairy prod­ucts, sim­i­lar before and after the nutri­tional tran­si­tion, did not affect health indi­ca­tors.”

To cor­rectly place all of the pieces of a very com­plex puz­zle, researchers are now work­ing with their col­leagues, who are study­ing the old­est res­i­dents of three other known blue zones: the Greek island of Ikaria, the Japanese island of Okinawa and Nicoya in Costa Rica.

“While feed­ing habits may rel­e­vantly dif­fer, we are now inves­ti­gat­ing the com­mons fac­tors,” Pes con­cluded.

• Nutrients