The discovery of the hormone GLP-1 has markedly changed the treatment options for people with type 2 diabetes and obesity, with a treatment effect that includes both better regulation of blood glucose and significant weight loss, while reducing the risk of complications arising. Professor Jens Juul Holst, MD, DMSc, is one of the world’s most recognised researchers in diabetes. He pioneered the work that discovered the GLP-1 back in the 1980s and in this book, we trace the research-historical footsteps in the search for the hormone that today represents a paradigm shift in the treatment of diabetes and obesity. Jens Juul Holst is recently the recipient of the Banting Medal for Scientific Achievement (2021), the Canada Gairdner International Award (2021), the VinFuture Prize Laureates (2023), the Tang prize Laureates (2024) and the Princess of Asturias Award for Technical And Scientific Research (2024).