Buettner traveled the world and identified four places, which he calls blue zones, where people seem to have a three times better chance to reach 100 than people elsewhere The Italian island of Sardinia has the highest number of male centenarians in the world while another island, Okinawa, Japan, has the longest disability-free life expectancy. In Loma Linda, California, a small community has a life expectancy that's nine to 11 years greater than that of otber people in the US. And middle-age mortality is lowest on Costa Rica's Nicoya Peninsula.