Children's Hospital at Vanderbilt. Simmons received her undergraduate degree from the University of Tennessee at Knoxville. She received her medical degree from the University of Tennessee at Memphis. She completed her pediatric residency and a fellowship in pediatric endocrinology and diabetes at the University of Colorado Health Sciences Center in Denver. Her research interests include studying the biochemical markers of hypothalamic obesity in newly diagnosed neuron-oncology patients and the prevalence of decreased bone mineral density and poor growth in patients with type 1 diabetes mellitus and celiac autoantibodies.