Gluten is a mixture of proteins found naturally in wheat, barley, and rye. When you mix flour with water and knead it into dough, gluten forms sticky, elastic strands that trap air bubbles and give bread its chewy texture. Without gluten, bread would crumble apart instead of holding together.

For most people, gluten is harmless and can be part of a nutritious diet. But some people have a condition called celiac disease, where eating gluten triggers their immune system to attack their own intestines, making them sick. Others have gluten sensitivity, which means gluten causes uncomfortable symptoms like stomachaches or fatigue. These people need to avoid foods containing gluten, reading labels carefully and choosing alternatives like rice, corn, or special gluten-free flour blends.

Bakers rely on gluten's properties: they knead bread dough to develop the gluten network that makes the bread rise tall and chewy. Pizza dough gets stretched thin because gluten makes it elastic rather than brittle.