Opinion: Are blue zones real? Answering that question is harder than ever

Men born in Costa Rica's Nicoya Peninsula in 1945 died younger than their peers elsewhere in the country. That is the finding that Luis Rosero-Bixby, the demographer who co-declared Nicoya a Blue Zone of exceptional longevity, reported in Demographic Research — and it is the finding that may be ending the Blue Zones story as the wellness industry understands it.

The numbers are stark. Males born in 1945 had 10% higher adult mortality rates than other Costa Ricans, while males born in 1905 had 33% lower rates. The exceptional longevity that defined Nicoya appears to be a cohort effect — people who survived to old age under particular historical conditions — not a persistent geographic advantage. "People born on the peninsula after 1930 are not experiencing the same longevity as those born prior," Rosero-Bixby writes. The zone that made Nicoya famous may have been a historical accident, a place where imperfect records combined with unusual conditions to create the appearance of something extraordinary.

A quarter-century after Blue Zones entered the popular imagination — built on pencil marks on a Sardinian map, expanded by a National Geographic cover story, and turned into a global wellness brand with nine books, a Netflix documentary, city certification programs, and corporate retreats — the scientists who created the concept are dismantling it themselves. Michel Poulain, the Belgian demographer who coined the term "Blue Zone" while mapping longevity in Sardinia, and Rosero-Bixby, who co-declared Nicoya, are now on opposite sides of a peer-review battle over whether the zones were ever real in the way the brand claims. Meanwhile, Saul Newman, a researcher at the Australian National University who won the 2024 Ig Nobel Prize for his debunking work, has published a preprint on bioRxiv arguing that clerical errors, natural disasters, and pension fraud better explain centenarian concentrations than any lifestyle or genetic factors. "The proportion of centenarians discovered in these discrete regions," Newman writes, is better explained by record-keeping artifacts than by unusual rates of exceptional longevity.

The American Federation for Aging Research (AFAR) entered with a formal definition in April 2026. Announced via EurekAlert, it requires three things for a region to qualify as a Blue Zone: evidence of exceptional longevity measured at ages above 70, demonstrated odds of reaching 100 that significantly exceed background rates, and administrative data accessible to outside researchers. Under this stricter standard, only Sardinia still qualifies — and possibly Ikaria, a Greek island with similarly rigorous records. Okinawa and Nicoya no longer meet the criteria. S. Jay Olshinsky, the AFAR committee chair, is also leading an unpublished paper with a direct title: "Are Blue Zones Disappearing?"

The Okinawa problem is distinct but related. A study in the Journal of Internal Medicine notes that the destruction of family registries during World War II may have introduced age inflation when records were reconstructed after the war. People claiming extreme old age in Okinawa may, in part, be victims of reconstructed paperwork rather than genuine longevity. The Okinawa that Dan Buettner described in his first National Geographic story was already a historical artifact by the time he described it.

Buettner disputes the AFAR committee's stricter standard, arguing that it applies criteria that exclude the very places where they were developed. He has also noted that longevity clusters remain observable in the original zones even if the precise mechanisms remain debated. His commercial interests are substantial: Blue Zones LLC, which he founded, was acquired by Adventist Health in 2020 and has since announced partnerships with the American College of Lifestyle Medicine. His nine books have sold over 1.2 million copies. Blue Zone certification programs — where cities pay consultants to redesign urban environments around the supposed habits of the world's longest-lived people — operate in hundreds of municipalities worldwide. According to Outside Online, Buettner said in an interview with the New York Times that Loma Linda — the California community of Seventh-day Adventists included in the original Blue Zones list — was added to his National Geographic story at the request of his editor who wanted a United States site included. Demographers, Buettner acknowledged, had not verified it.

The wellness industry built on these places has grown accordingly. Retreat programs promise participants the lifestyle secrets of the world's oldest communities at prices running to thousands of dollars per week. City governments that have adopted Blue Zone certification redesign parks, sidewalk patterns, and restaurant menus in pursuit of the allegedly exceptional longevity visible in the original zones. None of these programs can offer a simple answer to what their foundational science is now debating: whether those communities were ever genuinely exceptional, or whether they were snapshots of a data artifact that happened to occur in a specific place at a specific time.

Rosero-Bixy's own conclusion, buried in a demographic journal, is the most honest summary available. The longevity of the oldest Nicoyans appears real for the cohorts he studied. Whether it persists into the future — whether a place can genuinely be said to produce exceptional lifespans rather than simply having happened to record them — is a different question. His data no longer answers yes to it. The Blue Zones story, at this point, is not a story about whether wellness culture oversold a concept. It is a story about whether the underlying evidence ever warranted the claims in the first place — and about what happens to a global wellness industry when the scientists who built its foundations start publishing papers that say the zones are gone.