Olive Oil: Four decades ago, researchers from the Seven Countries Study concluded that the monounsaturated fats in olive oil were largely responsible for the low rates of heart disease and cancer on the Greek island of Crete . Now we know that olive oil also contains polyphenols, powerful antioxidants that may help prevent age-related diseases. Yogurt: In the 1970s, Soviet Georgia was rumored to have more centenarians per capita than any other country. Reports at the time claimed that the secret of their long lives was yogurt, a food ubiquitous in their diets. While the age-defying powers of yogurt never have been proved directly, yogurt is rich in calcium, which helps stave off osteoporosis and contains "good bacteria" that help maintain gut health and diminish the incidence of age-related intestinal illness. Chocolate: The Kuna people of the San Blas islands, off the coast of Panama , have a rate of heart disease that is nine times less than that of mainland Panamanians. The reason? The Kuna drink plenty of a beverage made with generous proportions of cocoa, which is unusually rich in flavanols that help preserve the healthy function of blood vessels. Maintaining youthful blood vessels lowers risk of high blood pressure, type 2 diabetes, kidney disease and dementia.