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Hair Regeneration, How is hair replaced?
How is hair replaced? Hair grows, falls out, and is replaced by new hairs. It might surprise you to learn that you normally lose about 80 hairs a day. The vital growing spot is attached to the hair, somewhere within the follicle near the papilla.
How is hair replaced? As hairs grow old, the hair bulb breaks away from the papilla. When the old hair is a short distance from the papilla, a column of cells is sent down toward it by the hair. This column of cells, the vital strand of the aging hair, is the spark that begins the generation of a new hair in the same follicle.
The new hair bulb, in its growth from the vital strand within the follicle, reaches down to the papilla of the preceding hair. The new hair shaft later grows upward to the skin’s surface. It displaces the old hair within the follicle. The old hair becomes loosened from the walls high up in the follicle and is either brushed or combed out without effort. A new hair will appear if the vital strand of cells was deposited by the former hair. However, when a hair leaves its follicle without depositing the vital strand, a new hair cannot develop. As a result, hairs may get thinner or gradually develop a condition of baldness Alopecia is the technical term for loss of hair. The three most common forms of hair loss are alopecia areata, pattern baldness, and telogen effluvin. Alopecia areata is a condition in which hair falls out in patches. The patches can vary from the size of a pea to several inches in diameter. There may be a few patches or the entire scalp may be affected. Other hairy regions of the body may also be affected. There is usually no pain, itching, or inflammation. The hair usually grows back over a period of months, but the condition can recur. Pattern baldness occurs most frequently in male, though females are not excluded. The hair recedes from the hairline toward the back of the head and also becomes very thin and recedes in the crown area. Telogen effluvin is a very common type of hair loss. This type of hair loss is connected with the way hair grows. At any moment, only about 80 percent of the hairs on your head are growing; the other hairs are resting. Each hair grows for two to six years during what is called the anagen phase. During the telogen phase, which lasts about three months, the hair rests. After this period, the hair falls out. This process goes on all the time, and usually we are not aware of it. Certain conditions, such as childbirth, surgery, serious illness, and emotional stress, can cause a great amount of hairs to enter the resting stage at the same time. After a few months, all these hairs are shed at the same time, and there seems to be a great increase in hair loss. However, this type of hair loss is only temporary and most of the lost hairs will be replaced. |