December 09, 2018
Birthday cake

Blue Zones: Hot Spots of Longevity

by Jeanine Barone

Some parts of the world, from a city in California to a far-flung isolated island in Japan, are populated by the world’s longest-lived people. It’s not so un­­common in those places to find centenarians and even some supercentenarians (110 years of age and older). These areas became known as Blue Zones, a term that came out of work initially done in the early 2000s by Michel Poulain, a Belgian demographer, and Gianni Pes, an Italian doctor, who identified a population in Sardinia’s Nuoro province that had the most male centenarians in the West. The investigators used a blue pen to draw concentric circles around the village clusters on a map.

Shortly after, Dan Buettner, an explorer and National Geographic Fellow, along with a team of epidemiologists, doctors, nutritionists, anthropologists, and demographers, set out to find other “longevity hot spots.” Buettner’s National Geographic cover story, “The Secrets of Living Longer,” ap­­peared in 2005; he subsequently wrote The Blue Zones: Lessons for Living Longer From the People Who’ve Lived the Longest and related books. Blue Zones is now a trademarked name.

Is it simply how these populations live or is it their genetic makeup that accounts for their longer-than-average life expectancies? Perhaps it’s a combination of the two.

Spanning the continents

Researchers have identified five areas that have a high proportion of people who live long lives with relatively few years of disability: the Ogliastra and Barbagia regions of Sardinia; Okinawa, Japan; the Greek island Ikaria; the Nicoya Peninsula in Costa Rica; and Loma Linda, California.

Sardinia has been called the “place where people live the longest in the world,” with one village (about 900 inhabitants) in the Italian island’s mountainous interior having had 20 centenarians during the past two decades. And unlike most other parts of the world, in regions of Sardinia, men and women live equally long lives.

Okinawa, part of an archipelago off the southwest coast of mainland Japan, has been dubbed “the land of the immortals.” On this island, 35 to 50 of every 100,000 inhabitants are centenarians. (That compares to an estimated 10 to 20 in 100,000 people worldwide.)

Ikaria, in the Aegean Sea, has been known as “the island where people forget to die.” A 2011 study found that 13 percent of 1,420 residents were over 80 in 2009—compared with fewer than 5 percent in Greece overall.

On the Nicoya Peninsula, situated on the Pacific coast of Costa Rica, a 60-year-old man has a four-fold better chance of making it to 90 than a 60-year-old American man. And in Loma Linda, the only Blue Zone in the U.S., people live up to 10 years longer than the average American. This city in the San Bernardino Valley in Southern California has the nation’s highest concentration of Seventh-Day Adventists, who are known for their healthy habits.

What they have in common

People living in Blue Zones share many traits: They eat plant-based diets that are rich in leafy green vegetables, fruits, whole grains, and legumes (though there are notable variations; see box). They tend to avoid added sugar and processed foods, and they don’t routinely overeat. They drink alcohol in moderate amounts, if at all. They are naturally active, often gardening or walking several miles a day.

But it goes beyond diet and exercise: Blue Zone inhabitants also tend to have a sense of community and purpose (both on an individual and collective level), maintain low stress levels, put an emphasis on family interactions, maintain lifelong friends, and participate in religious or spiritual activities. Interestingly, there’s a wide variation in smoking habits and obesity in Blue Zones.

Blue Zones: Who Eats What?

The diets and lifestyles of the long-lived people in "Blue Zones" (which include such places as Okinawa, Sardinia, and Ikaria) have many things in common. But the specifics depend on the location.

Nature or nurture?

A long healthy life is believed to result from the melding of environmental, lifestyle, and genetic factors, with genes ac­­counting for about 30 percent of the variance in human life expectancy overall, say researchers involved in the Okinawa Centenarian Study.

But according to the New England Centenarian Study, lifestyle factors appear to play an outsized role in survival until people reach their late 80s, while genetics may be a more significant factor in those who live into their 90s and be­­yond. Re­­searchers have, in fact, identified “longevity genes” and have found that centenarians and supercentenarians in particular have genetic profiles (“signatures”) in common that may be protective against a variety of chronic disorders such as cancer, cardiovascular disease, and dementia.

To put it another way, for the general population, lifestyle is thought to play a larger role in longevity than genetic factors, which means that living healthfully can add years to your life—up to a point. For people with certain genetic profiles, however, lifestyle may not matter as much, as was suggested by a study in the Journal of the American Geriatrics Society in 2011. It compared the lifestyle habits of 477 community-dwelling Ashkenazi Jews ages 95 years and older (based on present-day interviews) to those of more than 3,000 people born around the same time (based on data collected in a national study conducted years earlier) and found that the two groups differed in longevity but not in lifelong body weight, calorie intake, physical activity, alcohol use, or smoking.

The authors concluded that their study “suggests that people with exceptional longevity reach older ages despite lifestyle choices similar to those of the general population, supporting the notion that genetic factors related to exceptional longevity may also protect against the detrimental effects of poor lifestyle choices.”

Shades of blue elsewhere

Keep in mind that many other diets from around the world are also associated with good health and decreased mortality rates. They all tend to be plant-based—though some are quite different from Blue Zone diets. For instance, the traditional Mediterranean diet includes moderate amounts of olive oil, fish, and wine, none of which predominate in Blue Zones.

Other healthful lifestyle programs—for instance, the “Ornish Spectrum,” developed in the U.S. a few decades ago as a treatment for heart disease—also em­­phasize social support (connecting with others keeps us well) and stress management (such as yoga and meditation).

And, of course, as health experts around the world continually underscore, exercise (such as brisk walking most days of the week) is fundamental to good health.

Unfortunately, in recent decades, longevity has been declining (and rates of obesity and chronic diseases rising) in some Blue Zones, as inhabitants give up more traditional lifestyles. Notably, in Okinawa, increasing Westernization on the island, including an increased appetite for fast food, is taking its toll.