the nook at jensan

Image credit: michaeljung / 123RF Stock Photo

Each time you shampoo your hair, you loose a small percentage of it's natural protein.  The protein in your hair helps it to maintain moisture while working to prevent breakage—keeping it strong and healthy.  To help replenish the loss caused by shampooing, a protein-based deep conditioner should be part of your regular hair maintenance. According to an article by Tonya McKay on popular natural hair blog Curly Nikki,

Proteins have been used in cosmetics applications probably since the development of vanity in the human race. The beneficial properties of these natural substances were readily recognized and utilized, as illustrated in the tales of Cleopatra and her infamous milk baths.

Proteins adsorb readily onto the surface of skin and hair, forming moisture-retentive films. The films act to smooth and flatten the hair cuticle, which makes the hair shiny and more-easily detangled. These films can also provide some protection from the environment and pollutants. Proteins are generally hygroscopic, meaning they attract water molecules from the air, so they also act as humectants. Proteins added to bleaching or perming solutions have been found to significantly reduce damage to the cuticle, and their addition to dyeing solutions has been found to improve dye uptake into the hair while minimizing damage as well.

Most proteins used in personal care products have been hydrolyzed, a chemical method of breaking down the large structure of the protein into a smaller fragment of the primary structure (either a polypeptide or in some cases the amino acids themselves). These smaller polypeptides are more water soluble and thus more easily mixed into a formulation and also more readily absorb into the cortex of the hair.