Having friends is crucial for a fulfilling life: "Where would you be without them?"

Despite being 102 years old, Deborah Szekely remains as energetic as people much younger, and her social life is thriving.

Friendship, according to Szekely, is one of the most important factors contributing to her longevity.

She hosts workshops at her spa and fitness resort, Rancho La Puerta, every Wednesday and interacts with guests regularly. Szekely promotes living a long life by advising people to "find active friends" and often exercises with her close companions.

Szekely tells CNBC Make It that if you called them in the middle of the night and said "Help!", they would be in their car in five minutes, making them the kind of friends that count.

"Understanding and helping your friends is what friendship entails. It involves recommending good books, movies, and activities to do together."

Several centenarians were interviewed by CNBC Make It to determine the factors contributing to their longevity, and friendship emerged as a recurring theme.

Madeline Paldo, 100

Every Sunday, Madeline Paldo, who was 100 when she spoke to CNBC Make It last September, meets up with friends at Dunkin' Donuts with her son. "I look forward to that every week," Paldo said.

Frequently, her friends who are close in age visit her home for lunch.

"Paldo said, "They always call me, 'We're coming for lunch Wednesday at 12 o' clock,' and we have fun. But without your friends, where are you?""

Jayne Burns, 100

Jayne Burns, who was 100 when we spoke with her in July of 2023, emphasized the importance of finding friendly and kind people at work.

During her time at Joann Fabric and Crafts, Burns developed close bonds with some of her colleagues, including a Gen Z employee who taught her how to use TikTok during a coffee break.

Gladys McGarey, 102

Gladys McGarey, who spoke to CNBC Make It in April of last year at the age of 102, said that while finding one's purpose in life, one may accidentally discover their community.

McGarey stated, "People enter and exit your life, but it's up to you to select those who truly assist you."

Shirley Hodes, 106

According to Shirley Hodes, who spoke to us in March 2023 at the age of 106, close relationships are extremely valuable as they provide emotional support and help maintain motivation.

"The individuals around you, including friends, family, and relatives, have a significant impact on you, and it is these memories that will stay with you the most, as Hodes stated."

Research shows friendship is important for happiness and longevity

Since 1938, the Harvard Study of Adult Development has aimed to uncover the factors that contribute to happiness in life.

Positive relationships are linked to a longer lifespan and overall happiness, according to a study that tracked the health records of over 700 individuals for 86 years.

Social fitness is a process that happy, healthy people tend to through which they maintain their connections.

In an article from last year, Dr. Robert Waldinger and Marc Schulz, the directors of the Harvard study, stated that social fitness involves assessing our relationships and being truthful with ourselves about how we spend our time, in order to determine if we are nurturing the connections that support our well-being.

Frequent interactions and deep conversations can help maintain healthy relationships and lead to a longer, happier life, according to research.

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