Protein treatment is the process of smoothing and often strengthening hair. it called also a Brazilian protein treatment or a Brazilian blowout. It involves applying products to hair, blow drying it and sealing it with a flat iron. Keratin is a natural type of protein in your skin, hair and nails

During a keratin treatment, keratin is artificially added to the hair to make it look smooth, shiny and frizz free. Such treatments fill in the porous spots in your hair which materialized due to loss of keratin. These overly-porous hair cause frizz, tangles and breakage. A keratin treatment is basically rebuilding the hair by putting back the lost protein into your strands.

Protect hair from damage: Protein ingredients like hydrolyzed wheat protein or silk amino acids attach directly to the hair follicle and harden the cuticle layer. This places a barrier around the follicle, which protects it from further damage, says Ogboru.
Strengthen hair: Protein is the building block of the hair, Ogboru explains, so replacing protein that has been lost or damaged at the follicle rows away from the root helps to strengthen the entire length of the hair.
Improve elasticity: Hair lacking in protein will often stretch more than usual before breaking. A protein treatment will help to restore hair’s elasticity so that it stretches normally and then bounces back.
Help to eliminate breakage and split ends: In improving the strength and elasticity of hair, protein treatments help eliminate breakage and split ends. Ogboru adds that this can give the appearance of hair growth, as protein treatments prevent weak, brittle hair and stronger hair breaks less.
Enhances the overall appearance of hair: “Proteins will certainly impact the density, elasticity, and strength of hair. In addition, they will help to eliminate breakage and split ends and help hair reach its potential diameter, overall resulting in the appearance of more, better or healthy hair,” Shamban explains.