Michael Mosley investigates how cooking from scratch can be a simple way to eat healthier and avoid ultra-processed foods, many of which are associated with an increased risk of diseases like cancer, type 2 diabetes and heart disease. It doesn’t need to be complicated - simple recipes using tinned and frozen foods can be a great way to get started. Michael speaks to Dr Emily Leeming, a nutrition scientist from King's College London, to find out why cooking your own meals can be so beneficial for your gut microbiome, your waistline and your mental health. Meanwhile, our volunteer Richard cooks up a storm! Series Producer: Nija Dalal-Small Editor: Zoë Heron Commissioning Editor: Rhian Roberts A BBC Studios production for BBC Sounds / BBC Radio 4