Protein is an essential nutrient your body needs to take in every day to work properly. Protein is found throughout your body and is important because it provides energy and helps rebuild, maintain and repair body tissues, such as muscle and nervous tissue. Your body also uses protein to make new cells and to create specialized proteins, such as hemoglobin that helps carry oxygen to your body and support a healthy immune system.
Protein is made up of building blocks, called amino acids. There are 21 amino acids. The body makes 12 of them; they are called nonessential amino acids. The other nine amino acids must be consumed through food since your body cannot make on its own; these are called essential amino acids.1