Margaret Rayman is Professor of Nutritional Medicine at the University of Surrey, UK, and Visiting Professor and Honorary Director of the Clinical Research Center at the First Affiliated Hospital, Xi’an Jiaotong University School of Medicine, Xi’an, China. In 1998, she set up the highly respected MSc Programme in Nutritional Medicine at the University of Surrey. Her research, which includes a number of randomised controlled trials, centres on the importance of trace elements to human health with particular emphasis on selenium and iodine in populations with marginal selenium or iodine status. A Thomson-Reuters Highly Cited Researcher, she has published widely on the effects of selenium on human health including a number of highly cited reviews in The Lancet. As part of her extensive work on iodine, her group found a significant association between mild-to-moderate iodine deficiency in UK pregnant women of the ALSPAC cohort and poorer IQ and reading ability in their offspring at ages 8 and 9 (Lancet 2013). She is currently a partner in the Horizon 2020 EUthyroid project (http://euthyroid.eu/) that aims to harmonise and improve iodine intake in Europe, and is part of a work package to examine the effect of iodine on child neurodevelopment in cohort studies from three European countries (UK, Netherlands and Spain).