For thousands of years the question of extending life or living forever has occupied minds.  But now it’s taken on a new life, from peptides, to IV drips and experimental treatments targeting the heart or kidneys, there’s a buzz around longevity.  Today, Dr Norman Swan on his Four Corners investigation into the big business and the science behind the quest to live healthier for longer. Featured:  Dr Norman Swan, co-host of the Health Report and What’s that Rash on ABC Radio National