The industrialisation and commercialisation of food have transformed our diets, whereby most of our calories now come from an entirely novel set of substances. Ultra Processed Food (UPF) now makes up 60 per cent of the average diet in the UK and USA. It is highly processed, highly addictive, and largely unhealthy. Join award-winning broadcaster, practising NHS doctor and leading academic Chris van Tulleken as he explores the invention of UPF and its impact on our health and weight – from altering metabolism and appetite to an increased risk of cardiovascular disease and tooth decay.