Lead Sponsor: QOL Medical, LLC

Collaborators: Children's Hospital Los Angeles, Children's Hospital of Philadelphia, Massachusetts General Hospital, Columbia University, Duke University, Johns Hopkins University, University of Mississippi Medical Center, Children's Hospital Colorado, Children's Mercy Hospital Kansas City, Arnold Palmer Hospital for Children, Children's Hospital and Health System Foundation, Wisconsin, Ann & Robert H Lurie Children's Hospital of Chicago, Baylor College of Medicine, Nationwide Children's Hospital, Primary Children's Hospital, State University of New York - Downstate Medical Center, Riley Children's Hospital, Children's Hospital and Research Center at Oakland, Children's Center for Digestive Healthcare, LLC

Lead Sponsor: Massachusetts General Hospital

Collaborators: Nutricia North America

Intervention / Treatment: OTHER: product containing gluten and casein (milk protein) with GFCF diet, OTHER: GFCF product with GFCF diet