Tim Korevaar studied medicine at Erasmus University in Rotterdam and became interested in endocrinology, the subject that deals with the different hormone systems. This interest expanded while conducting research on various endocrine organs at the University of Oxford. After graduating he started a PhD program, guided by Robin Peeters and Theo Visser from Erasmus MC, exploring the determinants and consequences of changes in thyroid function during pregnancy. At the same time he completed a Master of Clinical Epidemiology at the Netherlands Institute of Health Sciences. The effects of iodine status on thyroid function of the mother during pregnancy and the brain development of the child are an important part of his current research.