Australia faces an obesity crisis with four in five older adults overweight or obese, prompting debate over subsidising new weight loss drugs like Monjaro and Zepbound. Dr Giles Yeo, Professor of Genetics at University of Cambridge, discusses the effectiveness of these medications in treating obesity and reducing risks of type 2 diabetes, heart disease, and certain cancers. The drugs work for most patients but require long-term use, with weight returning when treatment stops, similar to blood pressure medication.