What is protien feed used for in hair care?

Protein helps breakage and damaged hair because hair splits when there isn't enough protein to keep it together. Lots of salon products have protein shampoos and conditioners specially formulated for damaged hair. Redken has a really good line called Extreme. Extreme CAT is a protein spray and Extreme Deep Fuel are protein packets. If your hair is really bad then I would say do it once a week. Look for products specially formulated for damaged hair, more than likely it'll have protein in it, check out the ingredients. Lanza makes a shampoo called "Protein Plus" and Pureology has a line called Reconstruct Repair (thats the one I found really helped me). Either way, it's not going to hurt your hair so might as well give it a try.