Among the treats in the menu at a "longevity restaurant" (an eatery claiming to serve food that will make patrons live longer) in Ogimi Village, Okinawa, are silver sprat fish, chopped vegetables and crispy rice flour, and purple Okinawan potatoes. (Supporting image from the project Hungry Planet: What the World Eats.) Hara hachi bu: "eat only until 80 percent full," say older Okinawans. The island has been the focus in recent years of researchers trying to discover why a disproportionately large number of Okinawans are living to age 100 or more.