Do Blue Zones Really Exist? What the Evidence Says About Places of Long Life

Few ideas about long life have spread as widely as the Blue Zones: small places around the world where people supposedly live to 100 far more often than elsewhere. Books, documentaries, and diets have been built on the idea. But scientists have questioned the evidence behind it. This article explains both sides.

What are the Blue Zones?

Regions said to have many very long-lived people. Wikipedia explains that the idea began with the island of Sardinia in Italy and was extended in 2005 to Okinawa in Japan, Nicoya in Costa Rica, and Ikaria in Greece. A Gulf News report, based on AFP reporting, says journalist Dan Buettner wrote a National Geographic story that added Okinawa and Loma Linda, California. He then teamed up with demographers to create the Blue Zones lifestyle brand. Wikipedia notes that Blue Zones LLC, a commercial company, was formed in 2008, and was acquired by Adventist Health in 2020.

What is the criticism?

That the age records may be wrong. Saul Newman, a researcher at University College London, won the 2024 Ig Nobel Prize, an award for research that makes people laugh and then think, for his work on this. StepUp for Ageing Research reports on a study that had not yet been peer reviewed. He found that across countries only 18 percent of the oldest old have a birth certificate. He also found that the birthdates of supercentenarians were concentrated on days divisible by five, a pattern suggesting error or fraud. He described Sardinia, Ikaria, and Okinawa as regions with low incomes, low literacy, high crime, and short life expectancy relative to their national averages. He suggested that poverty brings age-reporting errors and pension fraud. AFP reports that Newman cited research showing that in Costa Rica 42 percent of centenarians had lied about their age in an earlier census.

What does the evidence on Okinawa show?

A mixed picture. Wikipedia notes that research on Okinawa found two generations with contrasting longevity: people born before World War II had many centenarians, but those born after 1945 showed no evidence of unusual longevity. It also reports that a 2024 review challenged the idea that Blue Zone communities have exceptional longevity, arguing there is no scientific evidence linking community lifestyle to it.

What do the Blue Zones researchers say?

That the ages were carefully checked. Buettner’s website says that the ages in each Blue Zone were rigorously validated with modern demographic methods, and that the criticism applies to places with poor records, not to the Blue Zones. It argues that poverty and low literacy do not affect how longevity is calculated. According to AFP, the demographers said they “meticulously validated” the ages by double-checking records dating back to the 1800s. They also accused Newman of referring to broader regions of Japan and Sardinia than the smaller blue zones.

What about Loma Linda?

Its place on the list has its own story. AFP reports that Buettner told The New York Times he included Loma Linda only because his editor told him he needed to find America’s blue zone. Wikipedia adds that a 2025 review said Loma Linda was included in the marketing after editors asked for a United States example.

So what should we believe?

That the question is open. The dispute is about the quality of data on extreme old age, not about whether healthy habits matter. Be careful about claims that rest on a single place or a commercial brand. For the science of how long humans can live, see Can Humans Live Forever?, and for the numbers, How the Life Expectancy of Americans Changed Over the Last Century.