Updated April 30, 2026 06:10PM
In a tiny island village in the Mediterranean, a senior man makes the 15-minute walk to the market to fill his bag with artichokes, olives, and tomatoes from the local, sprawling farms. Heavy produce slung over his shoulder, he navigates the cobblestone streets, hills, and steep stairs to his friend’s home to spend the afternoon chatting. On the way, he passes portraits of community elders on the building walls, which honor the exceptionally large population of folks in the area who’ve lived to 100 and beyond. This is life in Sardinia, Italy, which is one of the “Blue Zones,” or places around the world where people live exceptionally long, healthy lives.
While the concept of Blue Zones has existed since the early 2000s when National Geographic fellow and author Dan Buettner and a team of researchers discovered them, some of these regions may now be validated by a new, more scientifically rigorous definition. Drafted by a team of scientists with backgrounds in demography and aging, the new guidelines include measurements of how long people in an area are expected to live after 70 and the number of people who live to 100, relative to the three longest-living countries, which are currently Monaco, San Marino, and Hong Kong. The new criteria create a unified method for identifying these regions going forward, using simple metrics that are easier to verify.
These preliminary findings may help lend legitimacy to the overall Blue Zones concept. It’s faced criticisms over the last few years from naysayers like Saul Newman, Ph.D., a researcher at University College London, who argues that the Blue Zones’ locations in poor, isolated areas mean birth and death reports are subject to several methodological errors.
The Original Blue Zones
“These places all have huge reverence for older people,” Buettner tells Outside. “Unlike America, where your social equity peaks at about 30, here, the older you are, the more treasured you are.”
The new Blue Zones definition was released in a preprint academic article exploring how three of the original Blue Zones—Sardinia, Italy, Okinawa, Japan, and the Nicoya Peninsula, Costa Rica—are losing their longevity outlier status as the areas evolve. (The other two well-recognized Blue Zones of Ikaria, Greece and Loma Linda, California haven’t been researched in this context yet.)
The academic article hasn’t been published—it’s under review at a scientific journal and is likely to be printed in the late summer or early fall. But once it is, potential Blue Zones will have to clear the new bar to claim the official title.
“It’s always kind of been ‘Dan Buettner who came up with this idea and wrote about it for National Geographic.’ I don’t write in academic journals, and academic journals are the way that other scientists measure credibility,” Buettner tells Outside. “Now, because of this [new article], it’s going to be easier for other researchers to get grants to go to Blue Zones, because it’s not Dan Buettner [behind it], it’s this consortium of the best demographers on Earth.”
The notion of Blue Zones, named after the blue ink demographers once used to mark maps with high elderly populations, was first spotlighted in a feature by Buettner in National Geographic. The idea has led to his books like The Blue Zones: Secrets for Living Longer and his popular Netflix documentary Live to 100: Secrets of the Blue Zones.
When the Blue Zones were first being defined, Buettner and research teams at each location verified the age demographics of these regions in various ways. In Sardinia, they relied on the “extreme longevity index,” or the percentage of people born in the region who lived to 100, compared to the rest of Italy. In Okinawa, they looked at the number of centenarians per 100,000 people. In Nicoya, research teams identified how many 60-year-olds made it to 100, as well as the death ratio, or the death rate in Nicoya compared to Costa Rica as a whole.
“The bottom line was, when the original Blue Zones were validated [in the early 2000s by Buettner and his team], they used similar but different criteria,” S. Jay Olshansky, Ph.D., lead author of the article, emeritus professor of public health at the University of Illinois at Chicago, and former board member of the American Federation for Aging Research (AFAR), tells Outside. “[We wanted to] use a standardized set of criteria and re-evaluate all of them retrospectively.”
New Blue Zone Criteria
The first aspect of the new criteria is life expectancy after 70, or how many years people will likely live after they’ve become septuagenarians, which is estimated using historical death rates. The second aspect is simply how many people in a population reach 100. These regions’ numbers are then compared to the countries with the longest-living populations. If their metrics are higher than the stats from those countries, that makes them a true outlier.
The researchers for this new criteria decided to look at life expectancy after 70 because “people living in these Blue Zone areas aren’t really any different than anyone else in these populations before the age of 70,” Olshansky tells Outside. “But there’s something different about the people who have made it to 70 and older.”
Buettner says it’s not just genetics that influence these populations’ lower chronic disease incidence. He‘s linked that to nine healthy living principles he observed across all the Blue Zones, which include behaviors like walking more, eating a plant-based diet, finding ways to de-stress, like through daily naps or spiritual practices, and focusing on family and purpose.
When researchers applied the new Blue Zones criteria to the original regions of Sardinia, Okinawa, and Nicoya, and compared their stats to those of the longest-living countries from the early 2000s when they were identified (Japan, Hong Kong, and France), they cleared the bar, reinforcing their status as longevity hotspots at the time they were first discovered.
This potential finding adds to the body of research aimed at refuting critiques of the Blue Zones concept. Those criticisms are largely led by Newman and his pre-print paper examining possible faulty and fraudulent demographic record-keeping in these areas. A 2025 article in the journal The Gerontologist (penned in part by one of the original Blue Zones researchers), also rebutted Newman’s claims, pointing to the rigorous verification of birth, baptismal, marriage, military, and death records in the Blue Zones. (The Gerontologist article does not include Loma Linda, the most hotly contested Blue Zone. Buettner said in an interview with the New York Times that he added it to his first National Geographic story on the Blue Zones at the request of his editor, who wanted a U.S. city included; it wasn’t verified by the demographers who worked on the other Blue Zones with Buettner.)
What Are the Blue Zones Now?
Even as three of the original Blue Zones appear to be supported by the new defining characteristics, it doesn’t mean these places will still qualify when the current demographics are examined and compared to the longest-living countries today. A study from the journal Demographic Research shows that in Costa Rica, people born after 1930 aren’t living disproportionately long lives anymore. A 2024 paper shows that Okinawa has also fallen off the longevity map. The Gerontologist article similarly stated that Okinawa no longer qualifies as a Blue Zone.
“[These places] are coming under siege because of mechanized conveniences,” Buettner tells Outside. “There are more cars and American food culture, with its chips and sodas and fast foods, and social media is coming there. [The forthcoming article] will reveal the effects of Americanization on these Blue Zones.”
Still, Buettner says, not all of the aspects of the Blue Zones are disappearing. “There’s a realization [in these places] that the old ways of doing things have produced this extraordinary health, so there’s a big movement from younger people to preserve the old ways of making wine, preserve the old gardening techniques, preserve the old music. In that sense, there’s an effort to preserve [these areas],” he says.
As a few of the original Blue Zones fade, other places that weren’t longevity hotspots are now becoming ones. Buettner declared Singapore the sixth Blue Zone in 2023, noting that life expectancy there has greatly improved since 1960, with the number of centenarians doubling from 2010 to 2020. He argues this is due to recent health-promoting policies in the country.
Martinique was also named a new Blue Zone by demographer Michel Poulain, Ph.D., emeritus professor at Université catholique de Louvain, one of the original Blue Zones researchers. The same researchers who worked on the preprint academic article on disappearing Blue Zones have also submitted another article for publication (to come out in late summer or early fall, too) that uses the newly defined criteria to analyze a yet-to-be-named Blue Zone.
Many towns throughout the world now claim Blue Zone status as part of the Blue Zones Project, an initiative led by Buettner to encourage cities to implement changes that reinforce healthy habits associated with the Blue Zones. These changes earn the city a designation of certified “Blue Zones Community,” though they don’t have to have exceptional elderly populations, which can create confusion about which places actually qualify as Blue Zones. Possibly only Sardinia still qualifies, and maybe Ikaria, Singapore, and Martinique, but they haven’t been validated with the new definition based on their current demography.
As more places embrace public health measures shown to boost wellness, it’s possible these “Blue Zone Communities” could also become legitimate Blue Zones in the future. Buettner says the habits people should adopt aren’t sexy, but simple. And they don’t focus on avoiding aging, but celebrating it.
Kristin Canning is a freelance journalist with over a decade of experience covering health and the outdoors. As someone who loves to run but has a love/hate relationship with fitness culture, she’s written about the personal-crisis-to-marathon pipeline, the extreme quest to break the Everest speed record, and the ethics of the return of The Biggest Loser.