Why should proteins be present in human food?

Protein is a type of nutrient that is responsible for building muscle tissue. Accordingly, if a person does not receive them in sufficient quantities, he will begin to experience a deficiency of proteins necessary for the normal functioning of the body. It is important that proteins are easily digested, so it is preferable to get them from animal food (in particular, meat). Vegetable proteins such as soy and other legumes are much more difficult to digest.