(MODEL RELEASED IMAGE).The Matsuda family in the kitchen of their home in Yomitan Village, Okinawa, with a week's worth of food. Takeo Matsuda, 75, and his wife Keiko, 75, stand behind Takeo's mother, Kama, 100. The couple's three grown children live a few miles away. 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. (From the book Hungry Planet: What the World Eats)