If you live on the island of Ikaria, a Greek island in the Mediterranean, your chances of living into your 90s is more than 10 times higher than in the U.S. The islanders’ longevity secret? What they drink first thing in the morning.

Researchers investigating the Ikarians, the longest-lived people in the world, believe that their habit of drinking boiled Greek coffee first thing in the morning boosts their heart health and is a key element in their life expectancy.

The researchers looked at the types of coffee consumed by the people in their study and found that about nine out of 10 of them drank boiled, Greek coffee every day. The folks who had this type of beverage enjoyed better blood vessel function than those who consumed other kinds of coffee. Even in those with high blood pressure, boiled Greek coffee consumption was associated with improved endothelial function, without worrying impacts on blood pressure.

“Boiled Greek type of coffee, which is rich in polyphenols and antioxidants and contains only a moderate amount of caffeine, seems to gather benefits compared to other coffee beverages,” says researcher Gerasimos Siasos.