Secrets of the Blue Zones

While visiting Patrone, Dan and Dr. Oz enjoyed a meal prepared by his 65-year-old daughter. Families stay together in Nicoya, which is another important key to living a long life.

For lunch, she made corn tortillas from scratch. First, she soaks the corn in ash and lime to break it down. Then, she smashes it in a metate—a Central American stone mortar. Then, she cooks the corn patties without oil. "It's a lot of hard work, and there's no electricity, so she can't do it any other way," Dr. Oz says. "And it's a good workout."

This daily process of cooking tortillas is like an automatic workout. "You know, most Americans don't really exercise. A very small proportion," Dan says. "But in Nicoya, they'll be making lunch and it's like doing 25 reps with the free weights."