Centenarians – people who live to 100 – were once a rare breed but became increasingly common in the mid-late 20th century thanks to improvements in diet, healthcare and lifestyle.
However, a recent analysis by the Office for National Statistics (ONS) suggests that the number of centenarians in England and Wales may have peaked.
In 2023, there was a 0.5 per cent decrease in centenarians compared to 2022, with the total falling from 14,920 to 14,850. This drop is thought to be tied to the decline of the post-World War I baby boom generation, which had contributed significantly to the rise in centenarians.
So, how did so many people make it to this ripe old age? And can we learn from them to improve our own chances of living to 100, perhaps even reversing this recent decline?
It might seem logical to ask the oldest living people for their secret to longevity, but Dr Bradley Elliott, Senior Lecturer in Physiology at the University of Westminster, explains that this approach alone is not reliable due to a phenomenon known as survivorship bias.
Survivorship bias occurs when conclusions are drawn from a group that has survived, while ignoring those who didn’t make it, giving skewed or incomplete insights.
“A good example is successful business people. They might attribute their achievements to specific actions, using their success as proof,” Elliot says.
“However, those who followed the same path but did not succeed are overlooked. If we looked at their experiences too, we could learn from their mistakes and increase our chances of success.”
Take Jeanne Calment, for example, who holds the Guinness World Record for the longest human lifespan at 122 years and 164 days. She often attributed her remarkable longevity to a relaxed and carefree lifestyle.
She married a rich husband so never had to work, loved cycling and indulged in some habits that seem counterintuitive to a long life such as drinking wine and smoking cigarettes, even at a very old age.
But does that mean we should all become a gold-digger, quit our jobs and kick back and relax with a glass of red and a cigarette? We might like to believe so. But that would be ignoring all of the other people who did the same thing but didn't get anywhere near their 100th birthday.
“Everyone has that one relative who smoked like a chimney their whole life and still lived to 90. But some people just get phenomenally lucky,” says Elliot.
“Studying the oldest individuals can provide insights, but a more reliable approach would be to study people in their 60s over decades to identify factors that contribute to longevity.
“Health recommendations, such as the NHS guidelines for 150 minutes of exercise a week, are based on decades of research, combining human observational studies, animal research, and various other sources of evidence.
"It's a process of gathering the best possible information from multiple angles to make informed health decisions.”
Does the answer to eternal youth lie within the world’s ‘Blue Zones’?
This survivorship bias is an important consideration in the context of ‘Blue Zones’ – regions where an unusually high number of people reportedly live past 100. First identified by Dan Buettner in the early 2000s, these areas include Okinawa (Japan), Sardinia (Italy), Nicoya (Costa Rica), Ikaria (Greece), and Loma Linda (California, USA).
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Buettner and his team spent years studying these regions and outlined nine lifestyle habits, called the ‘Power 9’, that they claimed were the golden ticket to living longer. These habits include exercising by moving naturally, having a purpose, ‘downshifting’ routines to reduce stress, stopping eating when 80 per cent full, eating largely plant-based diets, drinking one or two glasses of wine per day, a sense of religious faith or belonging, putting families first and living in positive social networks.
The Blue Zones concept has since sparked numerous studies, cookbooks, and a popular Netflix documentary in 2023, bringing the idea into the mainstream.
“While Blue Zone findings provide useful lifestyle advice, such as staying physically active, being socially engaged, and not overeating, the recommendation of daily drinking is a perfect example of survivorship bias and how it can result in misleading advice,” says Elliot.
“In 2023, The World Health Organization published a statement that there is no safe level of alcohol consumption.”
Adding another string to the bow, Blue Zones have recently been subject to a whirlwind of controversy following new research by Dr Saul Newman of the Oxford Institute of Population Ageing.
According to Newman, many of the claims about exceptional longevity in these regions are based on flawed data, administrative errors, and, in some cases, outright porkies in order to commit pension fraud. For his work debunking these ‘Blue Zones’, Newman was awarded the Ig Nobel Prize this year – a satirical award that celebrates unusual or trivial scientific discoveries that “make people laugh, then think.”
Newman’s research reveals widespread misreporting of ages in Blue Zone regions. For example, in Sardinia, despite its reputation as a haven for centenarians, European Union statistics place the island between 36th and 44th in terms of longevity in Europe.
When Newman dug deeper, he found that many of these so-called centenarians had actually passed away, but their deaths were not reported to authorities. A similar thing appeared to be happening in Nicoya and Ikaria. In 2015, an audit of Greece's pension system revealed that 72 per cent of the 9,000 individuals over 100 were either deceased or had not reached the reported ages. Instead, relatives were just pocketing the money. Thank you very much, grandma. Rest in peace.
“Extreme old age records are a statistical basket-case and virtually none of our old-age data makes sense. There is no physical and reliable way to validate this data,” says Newman.
“Over and over again, ‘validated’ centenarians have turned out to be fakes. For a century, Pierre Joubert was believed to be the first validated 110-year-old, before he was discovered to be his own son.”
There's controversy around Jeanne Calment as well, who some researchers believe was actually her daughter, Yvonne, posing as Jeanne to avoid inheritance taxes. The French government has stood by its validation of her records, but the dispute over Jeanne's age remains unresolved in the scientific community.
“She burned her personal effects the moment she became famous, after all. But everyone chooses to ignore that little wrinkle,” says Newman.
Okinawa was also found to be guilty of unreliable age records. In 2010, a review by the Japanese government revealed that 82 per cent of Okinawans reportedly over 100 years old had already passed away, yet their deaths remained unrecorded.
Newman also found that Okinawan lifestyles don’t align with the ‘Power 9’ Blue Zone principles. For example, Okinawans' Blue Zone diet supposedly consists of large quantities of vegetables, particularly sweet potatoes.
“According to the Japanese government, which runs one of the largest nutritional surveys in the world, dating back to 1975 and covering 96 per cent of their citizens, Okinawa actually ranks dead last for vegetable and sweet potato consumption in the country,” says Newman.
“They also have had the worst body mass index (BMI) in Japan every single year since records began. Everything about these data is strikingly at odds with independent measurements.”
Casting further doubt, Newman claims that areas with the highest number of centenarians are also associated with poverty, missing birth certificates, high crime rates, and poor health. This is surprising, as you’d expect people who live longer to be healthier and wealthier.
“Centenarians smoke, drink, and generally do things that will put you in an early grave. It all points to pension fraud and poverty,” says Newman.
However, Professor Giovanni Mario Pes, of the University of Sassari and one of the leading figures in Blue Zone research, has some criticism of Newman's findings.
“We object to Saul Newman’s academically misleading and deeply flawed preprint papers, which have not been peer-reviewed by any scientist. The ages of individuals in the officially recognised Blue Zones have been thoroughly validated, and their exceptional longevity is well-documented," he says.
“His assertion that Blue Zones correspond to regions with high illiteracy, poverty, and crime is misleading. While some Blue Zones experienced delays in economic and social development, these factors have no influence on the calculation of longevity rates.
“Newman's unreviewed papers are both ethically and academically irresponsible and insult both the scientific community and the Blue Zone communities themselves, who take pride in their elders and culture of longevity.”
So what actually is the secret to living longer?
Throughout history, people have tried to defy the inevitable ageing process. From bizarre ancient methods like drinking liquid gold in Egypt and Medieval Europe to modern practices such as performing blood transfusions from younger people and cosmetic injections to plump and smooth our appearance. But at the end of the day, the key to a long life still comes down to living a healthy lifestyle.
It might seem logical to follow the lifestyles of those who live past 100 to increase our own longevity, but this approach is unlikely to work and could be misleading. While most of the Blue Zone advice is sound and healthy to follow, as previously stated, the suggestion of daily drinking could be harmful.
“Drinking two glasses of wine every day, as recommended by the Blue Zones, is a recipe for developing alcoholism and far exceeds the NHS guidelines for heavy drinking. If a doctor recommended this to their patient, they would likely be disbarred immediately,” says Newman.
To give yourself the best shot at a longer life, both Newman and Elliot advise not to take health advice from centenarians. They suggest sticking to the tried and tested advice we've known for years: maintain a balanced, nutritious diet, exercise regularly, get enough sleep, manage stress, build strong social connections, have good mental health, avoid smoking, and limit alcohol consumption. These lifestyle habits have been proven to support good health and lower the risk of disease.
While it would be nice if there were some magical rules to live by that allowed us to keep indulging in naughty habits like drinking and smoking, the reality is if you don’t prioritise your health, you could end up popping your clogs early.
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