Christie is the associate dean at the University of North Florida's Brooks College of Health and a professor in the department of nutrition and dietetics, where she has worked since 2001. She was named the University's Distinguished Professor in 2017. From 1988 to 1996, by appointment of the governor of Florida, Christie chaired the state's Dietetics and Nutrition Practice Council of the Agency for Health Care Administration, supervising activities of the council regarding licensure of dietitians and nutritionists.
She has published dozens of research papers and book chapters on the prevention and treatment of excess weight and obesity; nutrition in chronic disease prevention; and interprofessional collaboration in education and health care.
Christie is the editor of the Florida Academy of Nutrition and Dietetics' Manual of Medical Nutrition Therapy. In her lengthy service to the Academy, Christie chaired the Member Sponsor Review Committee, Professional Development Committee and Nominating Committee; served on the Licensure, Scope of Practice and Competition Work Group and Publications Committee; served several terms in the House of Delegates; chaired the Nutrition Counseling Task Force and the Ethics Committee; and is a past president of the Florida Academy of Nutrition and Dietetics. Christie received the Academy's 2010 Excellence in Practice in Dietetic Education Award and the 2007 Outstanding Dietetic Educator Award.
Christie is a graduate of Florida State University, where she also earned a master's degree and doctorate.