Are there parts of the world where people seem to live longer than others? If so, what are the reasons, and what can we learn from the people who live in these areas?

This article explores the idea of Blue Zones and answers questions about why the people who live in them have a reputation of living longer than people in other parts of the world:

  • What are ‘Blue Zones’?’
  • Where are the Blue Zones?
  • Why do people tend to live longer in the Blue Zones? 
  • What is the best researched Blue Zone?
  • Blue Zones in Europe: Sardinia and Ikaria
  • A Blue Zone in Central America: Costa Rica
  • An urban Blue Zone: Noma Linda, California
  • A man-made Blue Zone: Singapore
  • Blue Zone project communities
  • Are Blue Zones a myth?
  • If I adopt a healthier lifestyle will I live to be 100?
  • Conclusions

 

What are ‘Blue Zones’?

Blue Zones are ‘limited regions where the population shares a common lifestyle and environment and whose exceptional longevity has been accurately verified’. The term was initially coined by author Dan Buettner, a National Geographic Fellow, who has written many books on the subject. 

Where are the Blue Zones?

In the main five Blue Zone regions of the world – as identified by Buettner and his co-workers – it isn’t unusual for people to live active lives until they are nearly 100 years old or older.

Why do people tend to live longer in the Blue Zones? 

Are the people who live in these zones lucky, genetically blessed individuals who just happen to live in unusually healthy environments? Do they have better lifestyles? Do they eat better food than most of us? Do they have better social networks and social support systems?

 

There is no simple, single answer to any of the common questions about the Blue Zones!  

 

These regions tend to be geographically or historically isolated regions, where a traditional way of life has been maintained. For example:

  • Physical activity is continued to the age of 80 and beyond.
  • Food is locally grown and sourced.
  • There is strong family and community support, including for older people.

Where people have been able to enjoy the benefits of a traditional lifestyle, augmented by the improvements made, for instance, by modern medicine, this is likely to have been a potent combination.

What is the best researched Blue Zone?

The Japanese island of Okinawa is one of the best researched examples of a Blue Zone.

The traditional diet here is full of fruits and vegetables – especially leafy greens and sweet potatoes (rich in antioxidants). The diet is also low in meats, salt and sugar, refined grains, full-fat dairy products and saturated fats. This kind of diet is low in calories, high in nutrients, meaning that the risk from cardio-vascular diseases, some cancers and age-associated conditions is low.

This traditional diet and the Confucian principle of Hara Hachi Bu (‘Eat until you feel 80% full’) have been widely suggested to be linked to the longevity and the low risk of age-associated diseases within the population. Interestingly, there is a European equivalent to Hara Hachi Bu, a German saying which translates as, ’When it tastes best, one should stop eating’.

People in Okinawa are traditionally regularly active and have strong social networks; both of these factors are likely to help increase their longevity.

Interestingly, when some Okinawans emigrated to countries like the US, and as younger Okinawans adopted a more Westernised lifestyle (for example, a lifestyle with more fast food and less exercise) their health and longevity deteriorated. 

Blue Zones in Europe: Sardinia and Ikaria

Sardinia is an interesting example, particularly when it comes to men. It has one of the highest proportions of male centenarians in the world: the proportion of male newborns who go on to live to be 100 is around 15 per 10,000 births.

Again, this is thought to be driven by an active lifestyle and a low-calorie, high-nutrient diet (as with the Okinawan Diet), although here the closer comparison is with the Mediterranean diet.

Ikaria is a Greek Island where the Mediterranean diet is also thought to play an important role in the longevity of the population. The same positive factors keep emerging: good social networks, daily physical activity, avoiding smoking and ‘a sense of purpose’. The ‘oldest of the old’ participants name these factors as being an important part of their daily lives. 

A Blue Zone in Central America: Costa Rica

Nicoya, a peninsula on the Pacific Ocean side of Costa Rica, has also been identified as a Blue Zone. Buettner states that it has the world’s lowest rate of middle-age mortality, with an eight-fold better chance of reaching 100 than Americans.

This low rate of mortality has been attributed in part to the region’s calcium-rich water, healthy eating, family-based living, outdoor activity and commitment to a relaxed, stress-free lifestyle.

An urban Blue Zone: Loma Linda, California

We can’t all go and live on islands – most of us live in cities, so are there any urban models we should consider?

An example we can probably relate more easily to is Loma Linda in California. Loma Linda is a small city about an hour’s drive due east of Los Angeles. It has a population of around 24,000.

Loma Linda is not an island, it is not isolated, and in fact, it suffers from a degree of air pollution. However, people there live on average eight to ten years longer than the average American. So, what is their secret?

About half the residents in Loma Linda are Seventh Day Adventists – Protestant Christians who observe Saturday as their holy day and for whom diet and exercise are considered especially important. A combination of diet (mostly vegetarian, high in fats from nuts), exercise, no smoking, not drinking alcohol and the social support associated with church attendance seem to be important here.

A man-made Blue Zone: Singapore

Singapore has been recently identified by Buetter as the first man-made Blue Zone.

The average lifespan in Singapore has indeed risen as a result of policies including incentives to eat more healthily, an efficient public transport system, a park network to encourage people to walk more, and a world-class healthcare system. However, on the negative side, Singapore has a high cost of living, a very competitive education system and a stressful pace of life. It has been argued that the increase in lifespan may have more to do with medical advances than with a healthier lifestyle and the quality of life. In addition, as a result of a 10-year gap between lifespan (84 years) and healthspan (74 years), many people spend their last decade in poor health.

Blue Zone project communities

The nine principles learnt from the research into the Blue Zones – the Power of 9® – have been taken into communities across the United States to encourage a healthier lifestyle.

 The resulting policy and environmental changes have increased life expectancy, reduced obesity, and made the healthy choice the easy choice for millions of Americans.

Other completed projects include:

  • Albert Lea in Minnesota – the first of these Blue Zone project communities – was chosen because it represented a ‘typical’ American city.
  • the coastal Californian cities of Hermosa Beach, Manhattan Beach and Redondo Beach.
  • and in the state of Iowa, a town called Spencer was granted the first certification for the Blue Zones community.

 

In an age when poor health seems so intractable, [the Blue Zones project] has taken this community from a place of resignation to a place of hope.

Dr Vivek Murthy, former U.S. Surgeon General
(after his orientation to the Blue Zones projects)
 

 

Are Blue Zones myths?

Recently, however, the concept of Blue Zones has been called into question. A 2019 study in an unpublished preprint (not validated by peer review) reported that the communities within Blue Zones, contrary to expectations, had some of the lowest life expectancies in the world. Possible reasons suggested by the researchers for this discrepancy were misreported age data or even pension fraud (claiming other’s identities to receive a pension).

In response to these criticisms, Buettner stated how he and the team of researchers and scientists went to the Blue Zone regions to carry out a thorough validation of people’s ages using birth certificates, cross-referenced with church baptism records or other available local records. He also stressed that Blue Zones are places with the highest healthy life expectancy, where people reach their 90s with low rates of chronic disease.

It has also been suggested that the idea that a so called ‘Blue Zone diet’ is responsible for people living longer is based on speculation, not on solid science, and that other factors may be involved.

So, if I adopt a healthier lifestyle will I live to be 100?

Perhaps you will, but there are other factors the people living in these Blue Zones may also have in their favour – their genes. There have been suggestions of inherited ‘longevity genes’ and mental resilience in Sardinia and even theories of gene selection due to Darwinian ‘survival of the fittest’ in Ikaria – as up to 20% of the (‘less fit’) population is thought to have died due to starvation in World War II. However, common variations in three genes associated with long life spans are not found in all people with exceptional longevity, suggesting that multiple genes may be involved.

Many studies show that a healthy diet, regular exercise, not smoking, not drinking too much alcohol, participation in social and community activities and in groups with shared beliefs and values can all help our health and our longevity. These ‘longevity factors’ align closely with the Power of 9® principles above.

What can we conclude?

Research into the Blue Zones suggests that our lifestyle can influence our longevity, while variations in certain genes may also play a role.

We can increase our chances of a long and healthy life if we:

  • Don’t smoke and we don’t drink too much alcohol.
  • Eat a diet rich in fruit and vegetables and low in salt, sugar and fats.
  • Exercise daily and regularly – as part of our daily life.
  • Maintain a strong network of friends and family and participate in our community.
  • Live in areas where there is social equality and where people think about each other, not just about themselves. 

Reviewed by Barbara Baker, December 2023. Next review due in November 2027.

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