What Are 'Blue Zones' And Why Do People Who Eat There Live Longer?

For centuries, humans have searched for the mythical fountain of youth. It resulted in Spaniard Ponce de Leon sailing to the New World in search of it, while other stories in history spoke about a river that reversed the side effects of aging, per National Geographic. While no one has ever found this fountain that restores youth and vitality, there are places where people live longer, and it's not a myth but a scientific fact.

Found throughout the world, "blue zones" are where there is a high concentration of people living for 100 years or longer, per CNN. In each of these zones, there is a common environment and lifestyle that has been credited for the residents' longevity. Blue zones, according to NPR, are located in Europe (Italy and Greece), Latin America (Nicoya Peninsula, Costa Rica), Asia (Japan), and the United States (Loma Linda, California). What the blue zone residents have in common are that the people live active lives and are surrounded by social circles that encourage healthy habits. Additionally, family is considered central to life. 

How and what they eat also goes a long way to the blue zone residents living for ten decades, according to findings from author Dan Buettner, as reported by NPR. In addition to only eating until about 80% full, blue zone residents also consumed their smallest meal later in the day. But it's hard to imagine what a resident of Okinawa, Japan, eats is similar to the food dined on in Costa Rica.

The residents who live in the blue zones may be spread out around the world, but despite that, their diets have similarities. Per NPR, meat isn't often consumed in the blue zones. Instead, the residents primarily eat plants and lots of beans. When meat is consumed, it is about 3 to 4 ounces in size and is only eaten about a handful of times each month. Complex carbohydrates also play a key role in blue zones, such as peas, vegetables, and whole grains, according to CNN. 

The nutritional benefits of eating complex carbs are numerous, including that they are digested more slowly than processed foods, resulting in blood sugar levels staying more level (via Women's Health). Cow's milk is also not often consumed in the blue zones, and fish is eaten only about three times per week and in small amounts, per NPR. The key to a longer life may also be in what they are not eating: Highly processed, greasy, and sugary foods. As a result, people living in the blue zones also rarely have heart disease, obesity, cancer, and diabetes.

Each of the blue zones has a few key foods as part of their diets. In Ikaria, Greece, residents eat lots of potatoes, honey, legumes, wild greens, and drink goat's milk, explains NPR. Despite the United States being famous for its fast food, people in Loma Linda, Calif., tend to take a hard pass and dine on grains, fruits, nuts, and vegetables.