Gluten is a complex protein found in wheat, barley, and rye grains. A gluten free diet excludes exposure to any of the foods that have this protein in its ingredients. It is easy to understand that regular wheat bread or pizza dough has gluten in it. However, it is less easy to realize that wheat flour is often used in many processed foods and in recipes for many foods that are prepared in a restaurant. Moreover, for it to be considered completely gluten free, processed foods should be prepared in a kitchen or factory that has no cross contamination with grains containing gluten.The Federal Drug Administration has published new guidelines that define gluten free food as having less than 20 parts per million of gluten. Regulations regarding food labeling criteria require food to meet this standard to be labeled "gluten free." It is important to read the labels for all foods products. Aside from a gluten free designation, there may be food allergy statements that discuss the factory or kitchen where the product was manufactured.Many restaurants have gluten free menus or can accommodate the gluten free dietary needs of their customers, but it is important for the person to ask the server, manager, or cook directly about whether it contains gluten.