The ten places called blue zones, and which have good records
Suppose you are asked to name the places where people live the longest. A list of five comes to mind for many people. A 2025 review looked at what the research says.
A research team including Cristina Candal-Pedreira read the scientific literature on blue zones. They included 65 records. Those records pointed to ten regions that someone had called a blue zone.
They sorted the ten into three groups: well characterized, under investigation, and excluded. They based the groups on what each region's data showed.
The ten regions and how the 2025 review classified them
| Region | Group | What the review reports |
|---|---|---|
| Ogliastra, Sardinia, Italy | Well characterized | Higher longevity than the national average |
| Okinawa, Japan | Well characterized | Higher longevity than the national average |
| Nicoya, Costa Rica | Well characterized | Higher longevity than the national average |
| Ikaria, Greece | Under investigation | High life expectancy |
| Cilento, Italy | Under investigation | High life expectancy |
| A municipality in the Netherlands | Under investigation | Higher share of exceptionally long-lived people than other municipalities |
| Martinique and Guadeloupe | Under investigation | About 21 to 24 supercentenarian deaths per million people, against 3 in metropolitan France |
| Rugao, China | Under investigation | Fewer centenarians |
| Menorca, Spain | Excluded | Data inconclusive |
| Loma Linda, California | Excluded | No studies in Loma Linda itself |
A supercentenarian is a person who reaches 110. The Dutch municipality is not named in the review.
Only four of the ten are studied heavily. They are Ogliastra, Okinawa, Nicoya and Ikaria.
A second 2025 review came from a team led by the demographer who co-wrote the original Sardinian study. It lists Okinawa, Sardinia, Nicoya and Ikaria as validated, with Martinique emerging as a fifth. It sets the bar at a longevity level at least 50% above the national average.
The two reviews agree on three places. They differ on Ikaria. The first group calls it under investigation, and the second calls it validated.
Loma Linda is a case of its own. It is defined by a religious community, the Seventh-day Adventists, and not by a map. The data we found are for Adventists across California, and the 2025 review found no studies in Loma Linda.
To see whether the country around each place explains part of the pattern, we checked life expectancy at 60 for people of both sexes in 2019, using World Health Organization tables.
Years a 60-year-old could expect to live, 2019 (World Health Organization)
| Country | More years at 60 | Rank among 196 countries |
|---|---|---|
| Japan (Okinawa) | 26.7 | 1 |
| Italy (Ogliastra, Cilento) | 25.1 | 10 |
| Costa Rica (Nicoya) | 24.5 | 21 |
| Greece (Ikaria) | 23.7 | 33 |
| United States | 23.2 | 40 |
Ranks are our count from the World Health Organization table.
Japan stands first of 196 countries. Costa Rica stands 21st, ahead of the United States. Greece is 33rd. All four heavily studied places sit in countries in the top 33.
One study of Nicoya has this title: "The vanishing advantage of longevity in Nicoya, Costa Rica: A cohort shift." Blue zone researchers also say the edge these places once had may be fading.
The label "blue zone" covers places with very different amounts of evidence. Three have good records. Others are still being studied.
Which of the ten places have you heard of, and which were new to you? Tell us in the comments. Someone may want to know where to start reading.
Sources we read
Candal-Pedreira and others, Blue Zones, an Analysis of Existing Evidence through a Scoping Review, Aging and Disease, 2025 (PubMed record). https://pubmed.ncbi.nlm.nih.gov/40479568/
Same review, full text on PubMed Central. https://pmc.ncbi.nlm.nih.gov/articles/PMC13061570/
Same review, supplementary file with notes on each region. https://www.aginganddisease.org/fileup/2152-5250/SUPPL/supplFile_art_20250604083144.pdf
Empire on Demand, Blue Zones: The Evidence, the Critiques and the Lessons (summary of the 2025 review and of Poulain and others, American Journal of Lifestyle Medicine, 2025). https://empireondemand.com/learn/aging-science/blue-zones
The vanishing advantage of longevity in Nicoya, Costa Rica: A cohort shift (title of the study). https://www.researchgate.net/publication/374807486_The_vanishing_advantage_of_longevity_in_Nicoya_Costa_Rica_A_cohort_shift
World Health Organization, Global Health Observatory, life tables for 2019 (life expectancy at 60, both sexes). https://www.who.int/data/gho/data/indicators/indicator-details/GHO/life-expectancy-at-age-60-(years)
Joint statement by blue zone researchers, October 2024. https://www.bluezones.com/wp-content/uploads/2024/10/Demographers-Statement-10.2024.pdf
Tell us in the comments