Professor Peter Peeling is a sports physiologist at the Western Australian Institute of Sport and researcher at the University of Western Australia. Peter has devoted much of his research time to iron metabolism in athletes, which is one of the most common nutrient deficiencies particularly in female athletes. We talk to Pete about the role of iron, what happens when athletes are deficient in iron, how to diagnose and treat iron deficiency, and why some para athletes may be more at risk of iron deficiency.