Protein is considered the "building block of life," it's needed for just about every bodily function. It's needed for building and repairing muscles, as well as general function of all the tissues in our body. Proteins consist of 20 different amino acids, some of which are not produced in the body and must be consumed through food. And, if you're vegan, it can be harder to eat enough protein, so it's possible you're skimping on daily requirements. However, don't discount plant-protein, as there are some clear benefits . "