Jeanne Calment, a French woman, achieved an incredible feat of living to age 122, thus earning the honor of being the world's oldest person on record.

But before her passing, Calment met and discussed her life with Jean-Marie Robine, an expert demographer who studies the links between health and longevity. 

As a disclaimer, Robine says: "We have to keep in mind that a big part of the longevity of Jeanne Calment is due to just chance because it's just so exceptional."

However, there are some aspects of her life that likely contributed to her ability to live so long, he says.

3 likely reasons the world's oldest person lived to 122

1. She was wealthy

Calment benefitted from "growing up in a bourgeois family in the south of France, so she was living in a nice neighborhood," says Robine. 

This allowed her to go to school until the age of 16, which was not very common for women during that time period, he adds. She also went on to receive private classes in cuisine, art and dance until she got married at 20 years old.

Another factor that likely helped her live longer, and stress less, was that "she never worked," says Robine.

"She always had someone at home to help her," and didn't have to cook for herself or even shop for her necessities.

2. She didn't smoke cigarettes until much later in life 

Until marriage, Calment was not allowed to smoke, says Robine. "We have to remember where we were, at the end of the nineteenth century in a little town in the South of France," he says. 

"Of course it was absolutely forbidden, and impossible, for a girl, and specifically in a bourgeois family, to do that."

Yet just after getting married, Calment's husband offered her a cigarette. And though she was extremely happy to do something that she wasn't allowed to do before, "when she was smoking for the first time, she did not find it nice, and she quit smoking."

Interestingly enough, Calment didn't smoke for most of her life, but picked up the habit at around age 112 while living in a nursing home.

3. She had a great social life

With so much free time, Calment had "absolutely nothing to do except to take care of [herself], to visit France and have social activities," says Robine.

She spent most of her time attending social events and meeting new people, especially because "people were organizing balls at home."

With her husband, she was also able to travel often and go to Paris to see the Eiffel Tower, which was under construction at the time. "She was discovering this fascinating world at the turn of the nineteenth and twentieth century."

"Even if she [died] at the age of 119, it would have been exceptional, and it would have been the same with 120," says Robine. "But she [lived] to 122 and a few more days."

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