Chronic diseases are becoming more and more common as a person gets older. A person's lifespan and susceptibility to diseases are determined by genetics, yet lifestyle also plays an important role.

There are a few places in the world, called blue zones, where people have low rates of chronic diseases and live longer than anywhere else.

What are Blue Zones?

Blue zone is a non-scientific term given to geographic regions where the oldest people in the world can be found. This term was first used by author Dan Buettner who studies areas of the world where people live exceptionally long lives. These places are called blue zones when Buettner and his fellow researchers searched for these areas, using blue ink to draw circles on a map.

In his book entitled "The Blue Zones", Buettner described five known blue zones in the world. One is Icaria island in Greece where people eat a Mediterranean diet rich in homegrown vegetables, red wine, and olive oil. In Italy, there is the Ogliastra region of Sardinia which is home to some of the oldest men on the planet. These men live in mountainous areas where they typically work on farms and drink lots of wine.

Meanwhile, Okinawa in Japan is home to the oldest women in the world. They are known for eating a lot of soy-based foods and practice a meditative form of exercise called tai chi. In Costa Rica, people living in Nicoya Peninsula are known for their diet based around beans and corn tortillas. The Nicoyan people regularly perform physical jobs into old age and have a sense of life purpose called "plan de vida". Lastly, the only blue zone in the US is Loma Linda in California where people are strictly vegetarian and live in tight-knit communities.

While these are the only areas discussed in Buettner's book, there could be unidentified places in the world that can also be considered as blue zones. Numerous studies have found that these areas contain extremely high rates of nonagenarians and centenarians, or those who live over 90 and 100, respectively.

READ ALSO: Loma Linda Blue Zone: Why Do Its People Live Longer Than the Rest of the World?


What is the Secret of the Blue Zones?

Experts have found that genetics only account for 20-30% of longevity. This means that environmental influences, like diet and lifestyle, play an important role in determining a person's lifespan.

One thing common to people living in blue zones is that they primarily eat a 95% plant-based diet. Although most groups are not strict vegetarians, they only prefer to eat meat around five times per month. Another dietary factor common to people in blue zones is moderate alcohol consumption. They drink one to two glasses of red wine per day, which could prevent heart disease and reduce the risk of death.

Aside from diet, exercise is another factor that contributes to longevity. In the blue zones, people do not exercise purposefully by going to the gym. Instead, it is built into their daily lives through their daily chores. In addition to exercise, getting enough rest and a good night's sleep also seem to be very important for living a long and healthy life. People in blue zones get adequate sleep and often take daytime naps.

Additionally, there are a number of other social and lifestyle factors which are common to the blue zones. These include religious beliefs, having a life purpose, living together, and having a social network.

RELATED ARTICLE: Humans Aren't Even Close to Reaching Maximum Longevity, Controversial Mathematical Research Says

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