In this series of special editions of BBC Radio 4 podcast Just One Thing, Michael Mosley quizzes the world’s leading health experts on the best ways to live well. In this Stay Young Special, we hear from Professor Andrew Steptoe, Head of Behavioural Science and Health at University College London, who leads the English Longitudinal Study of Ageing (ELSA). We hear the top tips that Professor Steptoe swears by to keep youthful. How can having a sense of purpose keep you genetically young? Why can feeling younger make you physically youthful? And how can your social life keep you in your prime? And as this is a Just One Thing special, we'll end each interview by asking Professor Steptoe for the one single most effective health hack to help you stay young. Producer: Dom Byrne Production Manager: Maria Simons Exec Producer: Zoe Heron Specially composed music by Richard Atkinson (Mcasso) A BBC Studios production for BBC Sounds / BBC Radio 4.