This September, the Annals of Improbable Research awarded Dr. Saul Justin Newman the IgNobel Prize for demography for his work casting doubt on claims that ‘Blue Zones’ keep the secret to longevity. Rather than diet, sense of purpose or a culture of respect for elders, Newman says that poor record keeping and pension fraud may be behind the excessive number of centenarians in these feted regions1. Do these areas truly hold the key to extreme longevity or just some dodgy paperwork?
What is a Blue Zone?
Blue Zones are districts around the world where more people than usual live past 100 years. Researchers coined the term ‘Blue Zone’ when they used a blue pen to mark regions with a high number of centenarians (people older than 100 years) 2. Sardinia (Italy), Ikaria (Greece), Okinawa (Japan), Nicoya (Costa Rica), and Loma Linda (USA) make up the five official Blue Zones. These regions have long attracted attention from scientists, journalist and social media influencers, who believe their residents’ diets, low-stress lifestyles, and strong social connections are – among other factors – key to longevity.
At first glance, Blue Zones offer an appealing story. If we could all mimic the lifestyle of centenarians, we could all grow older, stay healthier, be more satisfied, be happier and live better lives. It’s an attractive thought that a few simple dietary changes could result in a future as an agile, happy 108-year-old. Adherents of the Blue Zone diet claim that the Mediterranean diet, rich in healthy oils, fish and vegetables is the secret to extreme age. Likewise, the diet in Okinawa, which is rich in sweet potatoes, fruits and oily fish seems to be linked to long and healthy life.
When you spend a few more minutes reading about it, however, you might start to wonder if we are getting the full story. Those with a suspicious mind might ask whether the concept of Blue Zones is built on unreliable data.
Suspect supernumerary supercentenarians
The first question we might ask, is do places in the Blue Zone really have more supercentenarians (people older than 110 years)?
Let’s begin by looking at where people live to extreme old age. Simple logic would suggest that the most populous countries would be a good place to start hunting for very elderly people, just by dint of size. China and India, the two most populous countries each list two supercentenarians 3. Two. This is not an error.
Japan, on the other hand, lists 765 supercentenarians since 1850, and Italy has recorded 245 since 1860 3. The US has had 1928, France 514, the UK 269 and Canada 194 verified supercentenarians3. These remarkably great ages are more likely be carried by a generally higher life expectancy in developed countries due the access to healthcare, the move to service economy and better nutrition. NB The UK is a outlier as a country that doesn’t have a ‘Blue Zone’.
In Japan and Italy, we would expect people to live longer than in China and India due to radically different routes to economic development and the lingering effects of colonialism and civil war. China and India, however, are also countries of over a billion people each, with pockets of vast wealth and vast inequality, so where are the missing centenarians among the super rich? Italy has 100 times as many recorded super elders while also experiencing periods of war and turmoil in the early 20th century.
Are Blue Zones the secret?
The answer, proponents would have you believe, is Blue Zones. The famed geographical subzones where people live a simple life with a diet of polyunsaturated oils, fish and vegetables.
In Blue Zones, they claim, there are even more elderly people than you would expect from looking at the whole of these relatively rich countries. For example, Okinawa boasts more supercentenarians than in any other region in Japan 4.
The story of Blue Zones rests on the argument that people in these regions live consistently longer than anywhere else. But are they really supercentenarians, or even centenarians at all?
Old age investigators
It is surprisingly hard to confirm definitively a person’s age. Authorities declared the oldest living man found so far, 116 years old when he died in 2013. Japanese researchers claim they found enough evidence to corroborate his story that he was born in 1897, despite the verification process highlighting two birth dates and three marriage dates 5.
The case of the oldest woman, Jeanne Calment, who died in 1997 at the age of 122, has provoked considerable controversy. Russian Gerontologist, Nikolay Zak, accused the supercentenarian’s daughter Yvonne of assuming Calmet’s identity after her supposed 1934 death. Zak’s allegations, however, have yet to be substantiated; rather an extensive validation process seems to have verified Calmet’s claim 6.
It is impossible to prove the age of every supercentenarian. It’s very likely that some, if not many, errors have crept into the paperwork or ’misrememberings’ have been recorded as fact.
Shaky foundations
This is where Dr. Saul Justin Newman comes in. A highly accomplished, interdisciplinary researcher, his expertise spans diverse fields, including demography, machine learning and biology. With an interest in extreme age demographics, stories of the Blue Zone enthralled Newman. What was going on in these super superannuated regions? Did the Blue Zone hold up to scrutiny?
Newman applied his meticulous demographic training to the problem. He carefully sifted through international and national databases listing age records and socioeconomic indicators, for example, income, education or employment rate.
Perhaps unsurprisingly, he found some suspicious patterns. For example, if birth registration is missing, funnily enough, more people live to become supercentenarians. In the US, the introduction of birth certificates led to a significant drop in recorded supercentenarians. A coincidence?
Italian jobs
In Italy’s Blue Zone, many of these apparently extremely elderly folk live in economically disadvantaged regions with high unemployment and low life expectancy for the general population. Blue Zones Sardinia and Ikaria, are the monetarily poorest and least educated, with the highest crime rates in Italy and Greece, respectively. Does this mean a ‘simple’ life is the secret to a long life? Is material deprivation the way to accumulate the years?
Sadly no. Newman’s research suggests that poor record keeping and even pension fraud in these regions could be skewing the numbers: in several documented cases, younger relatives take over the identity of deceased elders to continue claiming pension cheques.
Relative Gains
This phenomenon isn’t just found in the Mediterranean. In 2010, officials attempted to meet Japan’s oldest living man, Sogen Kato. Expecting tea and talk of the 19th century, instead they met a mummified corpse . He’d been dead for 30 years. His daughter had cashed pension cheques worth $106,000 since his demise. This incident kick-started a nationwide investigation, visiting elderly people who were regularly receiving government benefits. Authorities failed to find more than 230,000 pension cheque cashing centenarians 7.
Misbehaving junior relatives are not the only complicating factor in the story of Japan’s supercentenarians. In Okinawa, especially, documents are notoriously unreliable – the birth records of many people claiming to be over 100 years old were destroyed in World War II 4.
Bad diet and smoking ‘boost’ longevity
If we accept that the number of supercentenarians in the Blue Zones is only a little inflated, what is it about these areas that keeps people so healthy? Newman turned his expert eye to lifestyle statistics and found some interesting trends.
Blue Zone advocates contend that adopting the way of life of centenarians could improve your own lifespan. Diet is one critical factor, and the healthy Japanese diet is seen as a key element in Okinawa’s claim as a hub for longevity.
Confusingly, Okinawa has the lowest per capita intake of sweet potato, fruits, vegetables, seafood, taro, shellfish, root vegetables, pickled vegetables, and oily fish in all of Japan1. The Okinawan diet may work wonders, but it is not so common in Okinawa.
Equally surprising are Dr. Newman’s observations on smoking. In the Blue Zone Ikaria, 99% of men and 32% of women reported smoking at some point in their life 8. Although many ceased smoking later in life, it is startling that tobacco consumption seemingly had very little impact on longevity. Similarly, in Tokyo, the smoking rate in centenarians is much higher than in elderly between 80 and 100 years old 1.
Do the heavy smokers survive longer? From all we know about smoking, it is a potent way to shorten your life. It’s difficult to reconcile high smoking rates with longer life expectancy, unless they aren’t really as old as they say they are.
Does This Mean Blue Zones Are a Myth?
In his work, Newman does not debunk the concept of Blue Zones altogether. He does present observations that cast doubt on the idea. If unreliable data and maybe even fraud are inflating the number of extremely old people, it means that the Blue Zones need a more critical look.
The notion that there are ‘nine rules for a long life’, as the Netflix Documentary ‘Blue Zones’ suggests, is a compelling one. In reality, however, aging is a complex process, its code hard to crack 9. While the lifestyle changes proposed by Blue Zone enthusiasts seem reasonable to pave a long and healthy lifetime, they are not backed by science.
Does this mean we should disregard all their messages? When looking back on your life what matters most isn’t necessarily how long you lived, but how satisfied you were with the time you were given.
Although finding purpose, eating well and spending time with loved ones might not get you to 100, they can certainly enrich your years in this world. After all, what’s the point of living to 100 if you’re not enjoying it?
References
- Newman SJ. Supercentenarian and remarkable age records exhibit patterns indicative of clerical errors and pension fraud. Published online March 14, 2024:704080. doi:10.1101/704080
- Poulain M, Pes GM, Grasland C, et al. Identification of a geographic area characterized by extreme longevity in the Sardinia island: the AKEA study. Exp Gerontol. 2004;39(9):1423-1429. doi:10.1016/j.exger.2004.06.016
- Supercentenarians by country – Gerontology Research Group. Accessed October 17, 2024. https://www.grg-supercentenarians.org/supercentenarians-by-country/
- Poulain M, Herm A. Exceptional longevity in Okinawa: Demographic trends since 1975. J Intern Med. 2024;295(4):387-399. doi:10.1111/joim.13764
- Gondo Y, Hirose N, Yasumoto S, Arai Y, Saito Y. Age verification of the longest lived man in the world. Exp Gerontol. 2017;99:7-17. doi:10.1016/j.exger.2017.08.030
- Robine JM, Allard M, Herrmann FR, Jeune B. The Real Facts Supporting Jeanne Calment as the Oldest Ever Human. J Gerontol A Biol Sci Med Sci. 2019;74(Suppl_1):S13-S20. doi:10.1093/gerona/glz198
- The mystery of Japan’s missing centenarians. BBC News. https://www.bbc.com/news/world-asia-pacific-11299646. September 21, 2010. Accessed October 17, 2024.
- Panagiotakos DB, Chrysohoou C, Siasos G, et al. Sociodemographic and lifestyle statistics of oldest old people (>80 years) living in ikaria island: the ikaria study. Cardiol Res Pract. 2011;2011:679187. doi:10.4061/2011/679187
- Buettner D, Skemp S. Blue Zones: Lessons From the World’s Longest Lived. Am J Lifestyle Med. 2016;10(5):318-321. doi:10.1177/1559827616637066