A simple smile, a friendly gesture or an offer of help and friendship, could help us all live longer, healthier lives. International Day of Happiness (March 20) is celebrated by the United Nations as a way to recognize the importance of happiness in the lives of people around the world. There is scientific data that suggests people who embrace the benefits of a positive attitude, are rewarded with a greater sense of well-being. Catherine Sanderson is a psychologist and professor in Life Sciences at Amherst College in Massachusetts. In her book, The Positive Shift: Mastering Mindset to Improve Happiness, Health, and Longevity, Dr. Sanderson explores the science behind our mindset, and how, she says, anyone can learn to adopt a more positive outlook. In this LLAMA podcast interview, with Peter Bowes, Dr. Sanderson explains how kindness, gratitude and genuine friendships can help promote better physical and mental health.