A strand of hair is a very complex part of the human body, something that may come as a surprise to some of you. Hair begins appearing on the human body while it is still in the womb. A 22 week old fetus already has about 5 million hair follicles. What is interesting about this fact is that that is the amount of follicles you will have for the rest of your life, no more and no less.

Hair Anatomy

Hair consists of a follicle, which is embedded in the skin, and the shaft of hair which appears on our body. A follicle consists of various layers, each with its own specific function. The papilla can be found in the base of each follicle. The bulb is the bottom part of the hair strand and receives blood from its surrounding cells via the capillaries which are connected to the papilla.

Surrounding the follicle are two sheaths, inner and outer, which are designed to both protect the hair shaft from damage, and to help it grow out in the proper direction. Inner sheaths run next to the hair shaft, ending in the oil gland (sebaceous). Outer sheaths run into the glands aswell, but the end in the erector pili muscle. The erector pili muscle is the muscle that causes the hair to stand on end when the muscle contracts.Each hair shaft has three layers that is made up of keratin which is dead protein cells. The innermost layer of the hair shaft is known as the medulla, though not all hair shafts will have a medulla present. The second layer, known as the cortex, provides the bulk of the hair shaft. The hair color is mostly determined by the pigmentation contained in this layer. The outermost layer is called the cuticle.A series of overlapping cells forms the cuticle. The cuticle also gives luster and sheen to the hair.

How Hair Grows

Scalp hair grows at an average rate of only 0.3mm to 0.4mm per day, adding to a mere six inches per year.

The three stages of hair growth.

Catagen Phase

This transitional phase runs about two to three weeks. Approximately 3% of our hair would be in this phase at any given time. There is no hair growth during this period while the out portion of the hair root sheath shrinks and attaches itself to the root.

Telogen Phase

Approximately 15% of your hair experience this phase, also known as the resting phase. The resting phase lasts for around 100 days for the hair on your scalp and a lot longer for other hair on your body.

Anagen Phase

The anagen phase is a period of activity in which the hair cells are dividing and new hair starts growing. This phase usually lasts for anything between two and six years. Shorter growth periods are indicative of people who have trouble growing their hair long.

Hair Growth Disorders

Humans generally suffer from one of the two main hair growth disorders. Females are mostly affected by a condition called Hirsutism. It is defined as a condition where excessive thick and dark hair growth is experienced in areas typically reserved for males. The areas may include the face, chest, areolae or the area around the nipple. Hypertrichosis is the other common condition, causing excessive hair growth in areas of the body where visible hair is not normally present. Both of these conditions are treatable.

To learn more about hair regrowth visit www.HairRestorationNow.org

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