Gluten is a protein found in cereals such as wheat, rye and barley.
It is the gluten in flour that creates the dough structure when you bake bread. The dough can contain bubbles of carbon dioxide that are formed during fermentation, so the bread becomes airy. Gluten also gives pasta its elasticity and chewing consistency.
Oats is a good choice
If you are gluten intolerant, there are various gluten free alternatives. Wholegrain products like oats are a good choice, for example. You will then increase your fibre intake, which is good for your digestive system.