1- REASONS

Hairs are long structures consisting of keratin. Keratin is a protein, resistant to breaking and abrasion. Nails also have keratin structure. As other proteins found in human body, keratin also is a big molecule, formed of small molecules called amino acids. Amino acids are arranged in an order like the beads of a prayer bead and forms big proteins. The diameter of a single hair, though varying from individual to individual, is between 0,05 and 0,09 millimeters. Epidermis is the outermost tissue of the skin. Each hair comes out of a notch found in the epidermis. Hair composes of two parts: hair root and hair body.

Hair Root

Hair comes out of a hair root. This is a small pit, embedded in the fat layer of the scalp, resembling a tea glass. The utmost part of the hair root found inside the skin is called hair bulb. Hair bulb is composed of live and continuously divided cells. These cells produce long hair fibers of cylindrical structure. In the hair bulb, pigment producing cells that give the color of the hair are also present. These pigments are called melanin and the cells producing them are called melanocytes. Male sexual hormone (androgens) receptors are also known to be on these cells. A structure called dermal papilla and bearing a vein bundle is present at the bottom of the hair bulb. This structure is very important for the growth and nurturing of hairs. Each hair is surrounded by a hair root and an outer hair sheath. Epidermis begins where outer hair sheath ends. Some kinds of glands are present around and adjacent to a hair root. The most importants of these are oil (sebaceous) glands that release oil (sebum) that lubricates the hair

Hair Body

The part of the hair that comes out of the skin is called hair body. Hair body consists of keratinized dead cells, some substances keeping these together and an amount of water. The reason for a person not to feel pain when having a hair cut is this structure. Hair body composes of three layers. The innermost tissue is called medulla and is only present in long and thick hairs. Cortex, composed of keratin fibers forms the middle layer of the hair. Cortex gives the hair its elasticity, solidity and color. The outmost layer is called cuticle. This colorless and thin layer is composed of dead cell residues hanging on to each other as 6-10 layers and serves as a protector for the hair cortex

Hair Types

Throughout life, a person develops various types of hair:

Lanugo
Forms beginning from the 3rd months of pregnancy and sheds a little time after the delivery.

• Child hairs
  After lanugo hairs shed, eyelashes and eyebrows are the only hairs that remain on the head.
• Intermediate hairs
  Hairs that can be seen around the sexual organs and in the arm pits of each sex, and beard, moustache and chest hairs that only grow in males during puberty.
• Terminal Hairs
  Thick, colored hairs that are found on the arms and the legs.

What is male hair loss pattern ?

Hair follicles are under the control of hormones. Androgens and thyroid hormone (tyroxin) are the most important hormones. Some parts of the hair follicles are sensitive to androgens (male sexual hormones), and the others are sensitive to tyroxin. The reason of hair loss of male pattern or Androgenetic type hair loss is the reason that dyhdro- testosterone’s, a male hormone, leading to weakness. Androgenetic type hair loss is permanent and though dominantly occurs in men, it can be seen in women as well. This hair loss pattern of genetic (familial) origin, generally starts on the forehead and the on the top. Hair follicles sensitive to androgen first get weak and then are permanently lost. Since the hair follicles found on the nape and the sides are sensitive to thyroxin, they do not shed.

What are the reasons of pathological hair loss ?

Women or men, everybody complains from hair loss for a period of their lives and worries whether he/she will become bald. Hair loss can happen due to various reasons. Sometimes a serious illness can be the underlying reason. Any kind of ingested medicine (cyclosporin, anti-thyroid drugs, anticoagulants, drugs used in cancer therapy), radical changes in hormone levels (thyroid diseases, pituitary gland diseases, diabetes), severe physical or psychological stress, air pollution, infection in the hairy skin or skin diseases (psoriasis, eczema, lymphoma), nutrition disorders (protein and iron deficiency) can be the reason of hair loss. Severe hair loss can occur after childbirth or severe diseases, however this type of hair losses are generally temporary.