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How Does Hair Grow?

Have you ever wondered, how does hair grow?  Hair is essentially a protein that is made up of a follicle, root and bulb. The follicle, which is located deep in the skin, is attached to a tiny sebaceous gland and muscle fiber. Hair grows when the follicle collects and bundles old cells. The sebaceous gland and muscle fiber push the bundles up through the skin in a root sheath. This sheath has two layers, an internal and external layer. The external layer contains RNA that gives the hair its color and texture. The internal layer contains the hair fiber.

The hair fiber is actually a cuticle, constructed in exactly the same way as fingernail and toenail cuticles. When considering, how does hair grow, it has its own growth cycle with three phases Anagen, Catagen and Telogen.  Anagen is the phase in which the growth takes place. Cells in the root divide rapidly. They are bundled and added to the hair shaft. The length of this phase varies, based on location and individual genetics. Hair grows approximately half an inch, every 28 days. At the end of the phase, the follicle moves into the Catagen phase.

The Catagen stage in the process of how does hair grow, is a short transitional phase. Hair growth stops and club hair is formed. It is anchored to the skin by its root, and the flow of nutrients stops.  This is the beginning of the Telogen, or resting phase of hair growth. The hair follicle dies and is keratinized. This means the hair becomes a tough, fibrous protein. It is the same material as fingernails and toenails. When a new follicle forms beneath the skin, it may push an existing hair out of the scalp. This Exogen stage is also known as shedding.

Whether it is the hair on your head or arms or eyebrows, when answering the question, how does hair grow, the process and phases are all the same. The RNA at each location dictates whether it is fine or course in texture and what the color and length will be. The hair growth cycles vary by location, from person to person. For hair that grows on the scalp, the Anagen phase averages two to three years, but in some may last up to seven years. When considering eyebrows and other body hair, the Anagen phase is only four to seven months.

How Does Hair Grow