What's the secret to longevity? A recent study suggests one answer might be a daily cup of very strong Greek coffee.
The study published in Vascular Medicine focused on elderly residents from the Greek island Ikaria between the ages of 66 to 91 and found that those who drank boiled Greek coffee at least once a day (rather than just the filtered coffee popular in America) tended to have improved endothelial function, meaning they had the better functioning cells that lined their blood vessels, which could mean better cardiovascular health.
Researchers have been interested in Ikaria since it is one of the "Blue Zones" where people live well past 90 at a significantly higher rate than the rest of the world and up to three times the rate of Americans.
But a strong cup of Greek coffee is just one small component of daily life on this island. A 2011 study published in Cardiology Research and Practice found the island population's longevity could also be related to consistent physical activity, a healthy diet and taking a daily midday nap, which can help diffuse stress.
Dan Buettner, author of "The Blue Zones," worked with longevity researchers to study the habits of elderly Ikaria residents and says that part of the Ikarian's secret to a long healthy life is as much about how they drink their coffee as the amount. Buettner says Ikaria residents usually enjoy their coffee in a social setting after a midday nap and rarely rush to finish their coffee.
"They also have social interaction their whole life. If you're alone it's a known killer," said Buettner. "So drink your coffee with a friend."
Dr. Christina Chrysohoou, one of the authors of the study in Vascular Medicine, said the researchers plan to continue their work by investigating how meteorological conditions, minerals in the water and radioactivity could be affecting the age and health of the residents.
The" Blue Zone" term came from census maps that Buettner and other researchers would mark with blue pen to find centenarians. As they found them, they began to realize they were congregating in clusters or "Blue Zones," each cluster in exceedingly different regions of the world. In addition to Ikaria they found clusters in Corsica, Costa Rica, southern California and Japan.
Buettner says there is no one single dietary element or exercise that is common in these locations that can provide the key to a long life. While Greek coffee is a favorite in Ikaria, it's not exactly prevalent in Okinawa, Japan, which is famous for having a large number of centenarians.
"The problem is we keep looking for is a silver bullet," said Buettner. "The answer is a silver buckshot."
In Okinawa there are approximately 50 centenarians for every 100,000 residents, while in America there are only 10 to 20 centenarians for every 100,000 people.
Researchers working on the Okinawa Centenarian Study have studied 900 centenarians for years to understand why Okinawa residents statistically have longer and healthier lives, even compared to other Japanese residents. Similar to Ikaria, there is no one reason. Okinawans tend to lead active lives with a diet high in vegetables and soy products. They also rarely overeat as they practice "hara hachi bu" or only eating until they are 80 percent full.