High-protein, low-carbohydrate diets are the hottest thing at the moment, and has been like that for a long while. As a matter of fact, high protein diets were recommended since a century ago, and especially peecked in 1950 and 1970s.
Of course, protein is an important component of every cell in the body. Hair and nails are mostly made of protein. Your body uses protein to build and repair tissues. You also use protein to make enzymes, hormones, and other bodychemicals. Protein is an important building block of bones, muscles, cartilage, skin, and blood.