What does protein actually do for your muscles and body?

Protein is made up of amino acids, which are the building blocks your body uses to repair and build muscle tissue. When you exercise, you create small tears in muscle fibers, and protein provides the raw materials to rebuild those fibers stronger and larger. This process is called muscle protein synthesis. Beyond muscles, protein serves many other functions. It makes enzymes that drive chemical reactions, produces hormones like insulin, forms antibodies for your immune system, and helps transport molecules through your blood. Your body also uses protein to maintain skin, hair, nails, and organ tissue. Unlike carbohydrates and fat, your body has no dedicated storage system for protein, so consistent daily intake matters for keeping all these processes running properly.