What the world's longest-living people eat (and avoid)

Have you heard of “Blue Zones”? They are regions of the world — five of them, to be exact — where people live abnormally long. First identified by Dan Buettner through his work with National Geographic, they include Okinawa, Japan; Sardinia, Italy; Loma Linda, California; Nicoya Peninsula, Costa Rica; and Ikaria, Greece.

Buettner delved into the secrets of these populations in his first book, The Blue Zones, fleshing out their hidden keys to surviving and thriving. Now, his second book, The Blue Zones Solution, looks specifically at how the world’s healthiest eat.

Take specifically the people of Ikaria, Greece — Buettner’s personal favorite population. “When it comes to diet, they have three key things,” he tells Yahoo Health. “Ninety percent of their kilojoules come from plants, 65 per cent of their diet is complex carbs, and the third thing — and this is a supplement everyone should run out and buy — is beans. A cup of beans a day for longevity.”

Buettner says beans — a staple in all the Zone populations’ diets — may add three to four years to a person’s life. “They push out the unhealthy proteins, they’re great and affordable, and they set up the gut flora for healthy digestion,” he says.

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In addition to beans, a diet that wards off death seems to have other elements: meat just about five times a month, very little cow dairy, a handful of nuts a day (to add two or three years to your life), and absolutely no soft drinks.

Of course, eating is not just about the food. “Most of the lessons to longevity involve the crucial importance of having the right social network,” Buettner says. “It’s three to four other people who are eating well, so you’re not going over to their house all the time”and wrecking your diet.

Buettner’s discovery of the Blue Zones wasn’t easy. It all began when he landed his first assignment at National Geographic: “I had an editor at National Geographic, who said expeditions always needed to add to the body of knowledge,” he says. “One of the mysteries in the year 2000 was why the Okinawa people had the longest, healthiest lives in the world.”

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There was more to discover about long life, outside the people of Okinawa. In November 2005, he penned the magazine’s cover story, “Secrets to Longevity,” based on his research into Blue Zones. But it wasn’t easy to discover these regions.

“We had to reverse-engineer,” Buettner says. “Only 20 per cent of how long we live is in our genes; 80 per cent is the environment. What’s happening here?”

So Buettner’s team dug into the statistics. “We used longevity as a proxy,” he explains. “We looked at how many were born in a given spot in time, and how many in that spot had died. Then once you find those with the longest lifespans, what’s going on in these populations? What are they eating, how do they exercise, is there religion involved, are they hard-working?” The list goes on.

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In addition to food, Buettner found another big secret to living long: Having a sense of purpose: “It’s not something we generally talk about, because no one makes money off it, but a vocabulary for purpose is essential,” he says. “Studies show people who articulate purpose live eight to 10 years longer, and have half the rates of dementia.”

Why should you listen to lessons pouring out of the Blue Zones? They’re time-tested, says Buettner. “You can’t just look at a family, or one person,” he says — you have to look at what a population has been doing for decades.