Dr. Cornier is currently Professor of Medicine and Director of the Division of Endocrinology, Diabetes and Metabolic Diseases at the Medical University of South Carolina. Prior to that he received his undergraduate education at Vanderbilt University in Nashville, Tennessee where he received a bachelor of science in Biomedical Engineering in 1987. Dr. Cornier then attended the Medical College of Georgia in Augusta, Georgia, receiving his medical degree in 1992. He went on to do his internal medicine residency at Georgetown University Medical Center in Washington, DC from 1992 to 1995. He followed this with a fellowship in Endocrinology, Metabolism and Diabetes at the University of Colorado health Sciences Center in Denver, Colorado, which he completed in 1999. He was then on faculty at the University of Colorado with the Division of Endocrinology, Metabolism and Diabetes until 2021.

At the University of Colorado, Dr. Cornier was the Associated Division Head for Endocrinology as well as the Associate Director and Medical Director of the University of Colorado Anschutz Health and Wellness Center. He was the Director of the Clinical Intervention and Translation Core of the Colorado Nutrition Obesity Research Center and an Associate Director of the University of Colorado Obesity Medicine Fellowship Program. Dr Cornier was the Director of the Advanced Lipid Disorders Clinic and Lipoprotein Apheresis Program at University of Colorado Hospital and where he also ran a diabetes clinic. Dr. Cornier was also on staff at Denver Health Medical Center in Denver, Colorado from 1999 to 2016 as a general clinical endocrinologist and at Aspen Valley Hospital in Aspen, Colorado from 2017 to 2021.

Dr. Cornier is an active clinical and translational investigator with a primary research interest in understanding the complex regulation of food intake and body weight and in studying optimal interventions for weight management and metabolic health. He has also been involved in clinical trials for investigational treatments for lipid disorders and obesity. Dr. Cornier has been an active volunteer in important health-related associations, such as the Endocrine Society, American Diabetes Association, American Heart Association, National Lipid Association, and The Obesity Society.