Dr. Stephen Wangen is a licensed and board certified physician specializing in digestive disorders and food allergies. He is the author of "The Irritable Bowel Syndrome Solution" and "Healthier Without Wheat: A New Understanding of Wheat Allergies, Celiac Disease, and Non-Celiac Gluten Intolerance," the latter published in 2009. He has first-hand experience with his area of expertise, having been diagnosed with IBS and later a gluten intolerance in 1996 as well as a dairy allergy.