If something is truly genetically linked then dieting for you might as well be lipstick on a pig if you don't have the right heritage. There are a couple other places in Asia with similar levels of longevity. Hong Kong, Singapore, and South Korea come to mind. Maybe look into what similarities they share with Japan. For Europe there are the usual Mediterranean countries, including Israel. (For European demographics, remember to adjust for large numbers because population size vary wildly.)