Just like carbohydrates are classified as simple or complex, proteins also come in two varieties: complete and incomplete. Remember how proteins are made up of amino acids? Well, of those amino acids, nine are referred to as essential amino acids. Essential amino acids cannot be produced by the human body and must be obtained through food or supplements.
Protein is what allows you to rebuild your body and recover from the daily wear and tear you place on it. Often people associate high protein intake with gaining muscle, but that’s just one role protein plays in the body. Every day, your body is regenerating hair, skin, fingernails, and yes, muscle tissue. It uses amino acids to do this, so if you aren’t consuming enough from your diet, your body will start to rip apart and break down your muscle tissue to get those amino acids.