Why do some people live longer than others?
This question has captivated millions of people and inspired them to travel to the so-called “Blue Zones”, where the secrets of longevity are supposedly hidden. But what if this idea rests on shaky ground? New research suggests that it is.
- What are Blue Zones and how did the concept come about?
- What evidence supports or refutes their claims?
- What are the real factors for longevity?
What are Blue Zones?
Blue Zones are regions of the world where people are reported to live significantly longer and healthier lives. The concept was developed by Dan Buettner in his 2009 book “The Blue Zones: Lessons for Living Longer from the People Who’ve Lived the Longest. Examples include Okinawa (Japan), Sardinia (Italy), Ikaria (Greece), Loma Linda (California) and the Nicoya Peninsula (Costa Rica).
The most important characteristics attributed to life in a Blue Zone include
- Diet: Plant-based foods, moderate wine consumption and limited meat consumption.
- Activity: Natural movements such as gardening instead of sport.
- Community: Strong social ties and attractive life goals.
The simplicity is tempting: if you adopt a certain lifestyle, you will live longer. Although these factors appear to favour longevity, a closer look reveals inconsistencies. So do the claims stand up to scrutiny?
The shaky foundations of Blue Zone research
Claims about Blue Zones are largely based on anecdotal evidence and flawed data. Researchers such as Saul Newman and Tom Whitwell have pointed out problems that call their validity into question.
Incorrectly reported age data and data fraud
Many age data in the Blue Zones originate from unreliable or destroyed archives. For example:
- Only 18% of people over 110 worldwide have birth certificates.
- In Okinawa, 90% of the paper records were lost during the Second World War and were replaced after the war by American authorities upon verbal request.
When birth certificates were introduced in the USA, the number of registered centenarians fell by 69-82.
Economic factors
Overlooked regions labelled as Blue Zones, such as Sardinia and Ikaria, often have:
- Low income and low level of education.
- Higher crime rates.
- Shorter average life expectancy compared to the national average.
This stark contrast raises the question: are these regions really healthier, or do their inhabitants survive despite poverty?
Analysing the factors for longevity beyond the myths
- Prosperity as a real driving force
Studies repeatedly show that wealthier countries have a higher life expectancy. Prosperity enables access to better healthcare, nutrition and living conditions.- Average life expectancy in rich countries: 80+ years.
- Average in poorer countries: 60+ years.
- Social systems and access to healthcare
Universal healthcare and robust social safety nets play an important role in longevity. For example:- Japan’s healthcare system contributes to its high average life expectancy, regardless of the Blue Zones.
- Lifestyle in the Blue Zones
Beyond the economic factors, other characteristics of the Blue Zones contradict the idealised ideas about the effects of the lifestyle there:- Okinawa has the highest obesity rate in Japan and a low level of natural activities such as gardening.
- Life expectancy in Sardinia is below the Italian average.
Myths versus reality – conclusion
What can we take away from this? Lifestyle choices are important, but they are part of a bigger picture that is influenced by wealth, healthcare and data accuracy.
The appeal of the Blue Zone concept lies in its simplicity. But reality is more complex. Longevity results from a mix of personal habits, social relationships and systemic factors. Whilst adopting positive lifestyle traits is beneficial, it is important to look at aspirations critically.
So far, only one thing has been proven: statistically, wealthy people live longer. But even the correlation between social inequality and life expectancy is complex and influenced by various factors.
Health and physical activity
Wealthy people have better access to medical care and resources for a healthy lifestyle.
Subjective well-being
Research shows that subjective well-being, including life satisfaction, absence of negative emotions, optimism and positive emotions, contributes to better health and longevity. Wealthy people generally have more opportunities to engage in activities that promote happiness and well-being, potentially leading to a longer life.
Happiness in old age
A study conducted in Singapore found that happiness in older people is associated with a lower probability of all-cause mortality. Happy older people had a 19% lower risk of all-cause mortality than unhappy older people. Wealth provides resources for a comfortable retirement, which may contribute to a happy life in old age.
Biological factors
Research on the mTOR (mammalian target of rapamycin) signalling network, which plays a crucial role in regulating ageing and lifespan, suggests that metabolic factors influenced by diet and lifestyle can affect longevity. Better access to nutrition and healthcare for wealthy people may therefore enable them to optimise these biological signalling pathways.
To summarise, while wealth in itself does not guarantee a longer life, it does provide access to resources and opportunities that contribute to longevity. In addition, factors such as genetics, lifestyle and general well-being play an important role in determining life expectancy, regardless of wealth status. In contrast, Blue Zones per se probably have no significant impact at all.