Protein is used in all body processes and aids in the building and preservation of lean body tissue. (Anything in your body but fat).
Protein uses more energy to digest, so you burn more calories when you eat it.
The minimum amount of protein needed to survive is .36 gram per pound of lean body weight. There have been numerous studies showing that upwards or 2g per pound of body weight a day is not harmful.
For our purposes, higher protein intakes are helpful for building and maintaining muscle mass and keeping you satiated!