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Why people in ‘Blue Zones’ live longer

In certain part of the world, there are areas called “Blue Zones”, where people have low rates of disease and live longer than anywhere else, their common lifestyles indicating how they achieve this longevity and why they’re able to avoid the chronic diseases increasingly prevalent in old age.

"Blue Zone”, the non-scientific term given to geographic regions homing some of the world’s oldest people, was first used by author Dan Buettner, who was studying areas of the world in which people live exceptionally long lives. When Buettner and his colleagues were searching for these areas, they drew blue circles around them on a map.

In his book, The Blue Zones, Buettner described five known such zones:
Icaria (Greece), an island where people eat a Mediterranean diet rich in olive oil, red wine and homegrown vegetables.
Ogliastra, Sardinia (Italy): Home to some of the oldest men in the world, who live in mountainous regions where they typically work on farms and drink lots of red wine.
Okinawa (Japan): Home to the world’s oldest women, who eat a lot of soy-based foods and practice tai chi, a meditative form of exercise.
Nicoya Peninsula (Costa Rica): The Nicoyan diet is based around beans and corn tortillas. These people regularly perform physical jobs into old age and have a sense of life purpose known as “plan de vida”.
• The Seventh-day Adventists in Loma Linda, California (USA): A religious group of people: strict vegetarians living in tight-knit communities.

Studies have found these areas contain extremely high rates of nonagenarians and centenarians, or people living over 90 and 100, respectively.

Interestingly, genetics probably only account for 20%–30% of longevity. Therefore, environmental influences, including diet and lifestyle, play a huge role in determining your lifespan.

Diet and lifestyle factors common to people in Blue Zones

One thing common to Blue Zones is that those living there primarily eat a 95% plant-based diet. Although most groups are not strict vegetarians, they only usually eat meat around five times per month.

Numerous studies, including one in of half a million people, have shown avoiding meat can significantly reduce the risk of death from heart disease, cancer and other causes.

Instead, diets in the Blue Zones are typically rich in the following:

• Vegetables: Eating more than five servings of fruits and vegetables a day can reduce your risk of heart disease, cancer and death.
• Legumes: beans, peas, lentils and chickpeas, all rich in fibre and protein, associated with lower mortality.
• Whole grains: Also rich in fibre: help reduce blood pressure and associated with reduced colorectal cancer and death from heart disease.
• Nuts: protein and polyunsaturated and monounsaturated fats, and with a healthy diet, linked to reduced mortality: may even help reverse metabolic syndrome.

Other dietary factors defining the Blue Zones

For example, fish is often eaten in Icaria and Sardinia. It is a good source of omega-3 fats, important for heart and brain health, and linked to slower brain decline in old age and reduced heart disease.

They fast, and follow the 80% rule

Other habits common to the Blue Zones are a reduced calorie intake and fasting. Long-term calorie restriction may help longevity. A large, 25-year study in monkeys found that eating 30% fewer calories than normal led to a significantly longer life.

Studies in the Okinawans suggest that before the 1960s, they were in a calorie deficit – eating fewer calories than they required – which may be contributing to their longevity.

Furthermore, Okinawans tend to follow the 80% rule, (“hara hachi bu”), meaning they stop eating when they feel 80% full, rather than 100% full. This prevents them from eating too many calories, which can lead to weight gain and chronic disease. Studies have also shown that eating slowly can reduce hunger and increase feelings of fullness, compared to eating rapidly, possibly because the hormones that make you feel full only reach their maximum blood levels 20 minutes after you eat. Therefore, by eating slowly and only until you feel 80% full, you may eat fewer calories and feel full longer.

Fasting

Apart from consistently reducing overall calorie intake, periodic fasting could be beneficial for health. Icarians are typically Greek Orthodox Christians, with many periods of fasting for religious holidays throughout the year.

One study showed that during these holidays, fasting led to lower blood cholesterol and lower body mass index (BMI).

Other fasting has also reduced weight, blood pressure, cholesterol and other risk factors for chronic disease in humans. These include intermittent fasting, or fasting for certain hours of the day or certain days of the week, and fasting mimicking – fasting for a few consecutive days per month.

Alcohol in moderation

Blue Zone people have a moderate alcohol consumption. There is mixed evidence about whether moderate alcohol consumption reduces the risk of death. Many studies have shown that drinking one to two alcoholic drinks daily can reduce mortality, particularly from heart disease. However, another suggested there is no real effect once you take into consideration other lifestyle factors.

The beneficial effect of moderate alcohol consumption may depend on the type of alcohol. Red wine may be the best, as it contains a number of antioxidants from grapes. Consuming one to two glasses of red wine daily is particularly common in the Icarian and Sardinian Blue Zones.

In fact, Sardinian Cannonau wine, made from Grenache grapes, has extremely high levels of antioxidants, compared to other wines. Antioxidants help prevent damage to DNA that contributes to ageing, and thus, could be important for longevity.

Some studies have shown drinking moderate amounts of red wine is associated with a slightly longer life. However, as with the other studies on alcohol consumption, it’s unclear whether this effect is because wine drinkers also tend to have healthier lifestyles.

Other studies have shown that people who drank a 150ml glass of wine every day for six months to two years had significantly lower blood pressure, lower blood sugar, more “good” cholesterol and improved sleep quality.

It is important to note that these benefits are only seen for moderate alcohol consumption. Each of these studies also showed that higher levels of consumption actually increase the risk of death.

Exercise built into daily life

Exercise is an extremely important factor in ageing: in Blue Zones, people don’t exercise at gyms. Instead, it is built into their daily lives through gardening, walking, cooking and other daily chores.

A study of men in the Sardinian Blue Zone found their longevity was associated with raising farm animals, living on steeper slopes in the mountains and walking longer distances to work.

The benefits of these habitual activities have been shown previously in a study of more than 13 000 men. The amount of distance they walked or storeys of stairs they climbed daily predicted how long they would live.

Other studies have shown the benefits of exercise in reducing the risk of cancer, heart disease and overall death.

Recommendations from the Physical Activity Guidelines for Americans suggest a minimum of 75 vigorous-intensity or 150 moderate-intensity minutes of aerobic activity per week.

A large study of more than 600 000 people found that those doing the recommended amount of exercise had a 20% lower risk of death than those doing no physical activity. Doing even more exercise can reduce the risk of death by up to 39%. Another large study found that vigorous activity led to a lower risk of death than moderate activity.

They get enough sleep

Apart from exercise, adequate rest and a good night’s sleep are also important for a long, healthy life. People in Blue Zones get sufficient sleep and also often take daytime naps.

Studies have found that not getting enough sleep, or getting too much sleep, can increase the risk of death, including from heart disease or stroke. A large analysis of 35 studies found that seven hours was the optimal sleep duration. Sleeping a lot less or a lot more than that was associated with an increased risk of death.

In the Blue Zones, people tend not to go to sleep, wake up or go to work at set hours. They just sleep as much as their body tells them to. In certain Blue Zones, such as Icaria and Sardinia, daytime napping is also common.

Various studies have shown that daytime naps, known in Mediterranean countries as “siestas”, have no negative effect on the risk of heart disease and death and may even reduce these risks.

However, the length of the nap appears to be important. Naps of 30 minutes or less may be beneficial, but anything longer than 30 minutes is associated with an increased risk of heart disease and death.

The Blue Zone regions are home to some of the oldest and healthiest people in the world. Although their lifestyles differ slightly, they mostly eat a plant-based diet, exercise regularly, drink moderate amounts of alcohol, get enough sleep and have good spiritual, family and social networks.

Each of these factors has been associated with a longer life. By incorporating them into your lifestyle, it may be possible for you to add a few years to your life.

 

Healthline article – Why People in "Blue Zones" Live Longer Than the Rest of the World (Open access)

 

See more from MedicalBrief archives:

 

The Longevity Diet: How nutrition affects ageing and healthy lifespan – US analysis

 

Plant protein diets linked to lower risk of death – International evidence review

 

Mediterranean diet promotes healthy cellular ageing in women

 

Calorie restrictive diet may protect against age-related disease

 

Good lifestyle choices improve healthy longevity by 7 years

 

5-day fasting diet lowers risks for major diseases

 

 

 

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