At 102, Deborah Szekely is just as lively as people decades younger, and her social life is booming.
In fact, one of the most important things that Szekely credits for her long life is friendship.
She speaks at her spa and fitness resort, Rancho La Puerta, which she still helps run, every Wednesday, and mingles with guests several times a week. Szekely also encourages those who are looking to live a long life to "find friends who are active" and often gets her daily physical activity alongside her close friends.
"If you were to call them in the middle of night and say, 'Help!' [and] they'll be in their car in five minutes. Then there's the kind of friends that count," Szekely tells CNBC Make It.
"Friendship is understanding your friends, helping them. You know, recommending good books, movies, things we can do together."
And other centenarians agree. CNBC Make It spoke to several people aged 100 or older to learn what they credit for their longevity and friendship was a common theme.
Madeline Paldo, 100
Madeline Paldo, who was 100 when she spoke to CNBC Make It last September, goes to Dunkin' Donuts every Sunday with her son to meet up with friends. "I look forward to that every week," Paldo said.
A few of her friends that are around her age also visit her home often for lunch.
"They always call me, 'We're coming for lunch Wednesday at 12 o' clock,'" Paldo said. "We have fun. Without your friends, I mean, where are you, right?"
Jayne Burns, 100
"It's important to find people who are friendly and kind," at work, said Jayne Burns. She was 100 when we spoke with her in July of 2023.
At her job, Joann Fabric and Crafts store, Burns formed close friendships with a few of her co-workers, including a Gen Zer who showed her how to use TikTok during a coffee break.
Gladys McGarey, 102
While you're finding your purpose in life, you may stumble upon your community, said Gladys McGarey, who spoke to CNBC Make It in April of last year when she was 102.
"There are people who come and go in your lives, but you choose the ones who really help to support you," McGarey said.
Shirley Hodes, 106
"Close relationships are very important. They keep you going," Shirley Hodes told us back in March of 2023 at age 106.
"The people you're surrounded with, friends, relatives, family," Hodes added, have a major effect on you. "That's what you'll remember the most."
Research shows friendship is important for happiness and longevity
The Harvard Study of Adult Development has been running since 1938 with the goal of discovering what makes people happy in life.
After 86 years of tracking the health records of more than 700 participants, researchers were able to conclude that the happiest people who live the longest have positive relationships in their life.
But not only do happy, healthy people have those connections, they also tend to them through a process that the researchers call "social fitness."
"Social fitness requires taking stock of our relationships, and being honest with ourselves about where we're devoting our time and whether we are tending to the connections that help us thrive," Dr. Robert Waldinger and Marc Schulz, directors of the Harvard study, wrote in an article last year.
Treating the health of the relationships in your life like exercise by getting in reps through frequent interactions or strengthening them through deep conversation can lead to a longer, happier life, they found.
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