Keratin is a tough protein that is found in nature. The human hair is made up of 97% keratin and 3% water. Have you ever heard of keratin shampoos and conditioners, which are believed to help damaged and dry hair? Keratin is very durable, that's why it works so well to give back the strength and vitality that gets taken away by other products and styling tools.

Note from biology: A hair follicle anchors each hair into the skin. The hair bulb forms the base of the hair follicle. In the hair bulb, living cells divide and grow to build the hair shaft. Blood vessels nourish the cells in the hair bulb, and deliver hormones that modify hair growth and structure at different times of life.

More Info: wikipedia.en.com