According to a report in a Johns Hopkins Medical Institutions publication, diets containing soyfoods have contributed to the longevity of people of Okinawa, the southernmost island of Japan, who have lived to be 100 years of age or older, reports Foods for the Future. The report is published in the September issue of the Johns Hopkins Medical Letter, "Health After 50," and presents a study of 600 Okinawan centenarians. The study found that the centenarians shared certain lifestyle factors, one of which was a low-calorie diet that included an abundance of soyfoods, vegetables and fish. According to the report, other common factors among the group of healthy elderly were regular physical activity, moderate alcohol intake, and "strong belief systems and social networks." According to the publication, Okinawans have 80 per cent fewer heart attacks than Americans, and 75 per cent fewer cancers, including breast cancer and cancer of the ovaries in women and prostate cancer in men. Previous health studies have attributed the role of soy, which is consumed in much greater amounts in Asian diets than in American diets, to better health among Asian residents, particularly in avoiding cancers and cardiovascular diseases. Okinawa has the highest proportion of centenarians in the world, with more than 33 are aged 100 years or older.