Undernutrition is a widespread problem that needs to be addressed with sustainable solutions. Daily diets require small amounts of the micronutrients iodine and iron to boost mental and physical development. Recognizing salt as a staple in diets, Venkatesh Mannar, overcame the technical and chemical challenges and pioneered a viable solution: double fortified salt (DFS). Protecting people from iodine deficiency disorders and anaemia, the use of DFS has been implemented as a public health prevention strategy worldwide. In this audio interview, Stanford Center for Social Innovation correspondent Sheela Sethuraman talks with Mannar, 2010 Tech Award winner in Health, as he discusses the large-scale social impact double fortified salt has brought to improving health and nutrition.