Hair, like a tree consists of a trunk (stem) and root. The hair shaft is its visible part that extends above the skin surface. The root of the hair is under the skin, in particular the deepening of - hair follicle. The lower extended part of the root of the hair is called hair follicle (hair follicle). Due to it is growth of hair.
For the color of the hair cells respond melanocytes located in the hair follicle. They synthesize hair colour: brown-black eumelanin and yellow pheomelanin. Their combination determines the color of the hair. And the melanocytes are formed from stem cells.
With age hair follicles wear out. It shows, first, that the reduced number of melanocytes in the hair follicles. The researchers found that the older the person, the less he has in the hair follicle stem cells. In older people, aged 70-90 years, no longer exists. The second factor causing graying - reducing activity of the remaining melanocytes. With age gradually reduced and then completely stops the activity of the enzyme tyrosinase, which is responsible for melanin production. Believe that the important role played by the hydrogen peroxide - the same with which lighten the hair to be blonde! The older we get, the more peroxide accumulates in the melanocytes. The hydrogen peroxide disrupts the synthesis of the enzyme tyrosinase. In addition, the hair appears there is a large amount of air bubbles. Thus, discolored hair from the inside out and turn gray, and then completely white. In the hair appear first single gray hair, and then they are becoming more - person greyish.
The start time of this process, genes, and to postpone its not any diet or lifestyle. If the bloom had already started, stop it, too, is impossible.
But there are cases when people turn gray for a very short period of time, after some strong emotions or stress. The mechanism of this phenomenon is not yet understood.
DID YOU KNOW THAT...
- ...men gray much earlier than women. This genetic predisposition, and fight with it until it is impossible.
- ...only men are gray due to stress.
- ...men beard and moustache turning gray before the hair on the head and torso. Women first white strands appear, usually at the temples, and then on the crown and nape.
- ...premature graying can be caused by metabolic disorders, liver, hormonal system, or diseases in which ceases to produce the pigment melanin. Such early gray hair can be prevented with a balanced diet, avoid stress, regular checkups at the doctor and timely treatment.