Research points to increasing importance of protein among younger and older individuals. Research has also has shown that not all proteins are the same -essential amino acids (EAA), which are the building blocks of protein, cannot be synthesized in the body and must be supplied by the diet. In general, plant proteins do not contain all of the EAA in sufficient quantities when eaten alone. While protein is found in both plant and animal foods, animal-based proteins have been shown to be more bioavailable and more readily useable by the body. Read more at BeefBoard.org