Emily and Amy speak to Alistair Black (Leeds Beckett University, UK) about his research into carbohydrate metabolism during exercise, and Barbara Cannon (Stockholm University, Sweden) about brown adipose tissue. They also discuss: Could Violet Beauregarde really have turned into a blueberry in Willy Wonka and the chocolate factory? Does eating breakfast kick-start your metabolism? And how can our body tell if a crisp is stale?