France produced 2 of the world's oldest people: Here's what the French do differently to stay healthy

Most people are lucky to live to 100, but two women lived far beyond that, joining the ranks of the world's oldest people — and they're both from France.

Jeanne Calment is believed to be the world's oldest person on record, gracing the Earth for 122 years. And recently, a French nun named Sister André was the oldest person in the world until Jan. 17, when she passed at the age of 118.

It's hard to pinpoint what exactly helps people live beyond age 100, considering the varying behaviors of supercentenarians, says Jean-Marie Robine, an expert demographer who studies the relationship between health and longevity. 

But there are certain factors that may give France the upper-hand on longevity, says Robine, who is also a research director at the Institut National De La Sante et de La Recherche Medicale (INSERM) in France.

Here are some reasons why people from The Hexagon tend to have some bonus years.

1. Education is free

"The most educated people have a longer life expectancy," says Robine. "They value more longevity [and] more good health. They have better knowledge about what to do [and] what not to do if you want to stay healthy." 

People who have received more education also have a better understanding of which foods to eat for longevity and which exercises to include in their daily life to increase their healthspan, according to Robine.

2. Access to healthcare is free

The countries with the highest life expectancies, including France, Japan and Denmark, all provide free healthcare. 

"And this is an important difference," says Robine, when comparing life expectancies of different countries, "and here we lose countries like the U.K., the Netherlands and the United States."

3. Better dietary choices

Residents of the South of France, where Jeanne Calment and Sister André were both born, adhere to a Mediterranean diet, says Robine. A Mediterranean diet prioritizes fruits, vegetables, whole grains, seafood and healthy fats — while limiting, or cutting out, consumption of red meat, dairy and sweets.

When you compare the North of France to the South of France, there's a two-year difference in life expectancy, which can be partly attributed to diet. Weather is also an important factor, as the winters and summers in the South of France are less harsh than in the North, he adds.

In relation to diet in other countries, Robine says, "people are eating too [much] fat and salt."

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