Protein is an essential part of cells and tissue, with two main protein types: albumin and globulin. Albumin helps prevent fluid from leaking out of blood vessels, while globulins are important for your immune system. High protein levels can place a burden on your kidneys, liver, and bones, as well as potentially increase your risk of heart disease and cancer. A lack of protein can produce several symptoms, including illness, increased infections, and reduced muscle mass.