1 United States Air Force School of Aerospace Medicine, Aerospace Education and Training Division, Wright-Patterson AFB, Dayton, OH, 45433, USA.
2 Department of Health Behavior, University of Alabama at Birmingham, Birmingham, AL, 35294, USA.
3 Departments of Internal Medicine- Gastroenterology and Pediatric Endocrinology, Massachusetts General Hospital Weight Center, Harvard Medical School, Boston, MA, 02114, USA. fstanford@mgh.harvard.edu.