How can we live longer, healthier lives? It’s a question that for centuries has enticed explorers to travel the globe and many others to suffer through everything from chemical peels to bizarre diets.  Is the secret in a good attitude? A lasting marriage? Strenuous exercise? Can we control it at all?  Leslie Martin, along with Howard Friedman, is the author of a new book called “The Longevity Project: Surprising Discoveries for health and Long Life from the Landmark Eight-Decade Study.”  Leslie Martin talks about the book, and dispels some long-held myths about longevity.