Gluten is a protein found in some grains that acts as a binder and adds elasticity to foods. Learn about the health benefits of gluten , the conditions that make it harmful, and how to follow a gluten -free diet. Gluten is a protein in wh eat and a few other grains. It’s not bad for most people, but some have health conditions that make it hard for them to digest gluten. GLUTEN definition : 1. a protein that is contained in wheat and some other grains: 2. a protein that is contained in…. Learn more. Gluten is a protein in certain grains, like wheat. Some people with medical conditions like celiac disease, IBS, or a wheat allergy may need to avoid it. Learn more.