Men and women lose a certain amount of hair each day. A loss of 70 to 100 strands is barely noticeable. Healthy scalps offset this loss by a cycle of regrowth. This regrowth cycle occurs in three phases. The initial growth period, called the anangen phase, lasts generally from 2-5 years. This growth phase is terminated by extreme interruption between the hair shaft and the nourishing papilla. This interruption lasts only a few days and is known as the catagen phase. The following 3-6 months is known as the telogen phase, in which the hair rests, held only in place by mechanical forces until eventually dislodged. Thus the cycle of growth begins again.

The most common type of hair loss is hereditary Male Pattern Baldness: 25% of all men under 30, and two thirds of men over 40 experience it ( Health News, University of Toronto Faculty of Medicine, Vol.. 6 #4). This type of hair loss is irreversible and can onset as early as teenage years to late middle age. Normally, MPB starts to thin on the top of the head and/or the hair line recedes further and further back towards the crown. In some cases of MPB, there will be a more pronounced loss near the crown.

Confirming the type of hair loss you have, makes it possible for you to know which treatment options are best for you.

The Growth and Development of Hair

Scalp hair provides no physical function for humans, but when excessive hair loss occurs, the psychological effects can be profound. Unfortunately, hair is not a permanent body part. Hair grows out of follicles located in the epidermis and dermis layers of the skin. At the base of each follicle is the derma papilla, containing nerves and blood vessels responsible for maintaining and continuing healthy hair growth. To form a new hair, a signal is sent to the immature cells in the bulb area of the follicle. The immature cells then migrate towards the papilla and are triggered to divide and mature. In approximately three months, a new hair develops and grows beyond the surface of the skin. Daily hair loss is a natural biological occurrence. Normal hair loss may be between 50 - 100 hairs per day. At any given time 90% of a healthy head of hair should be in the Anagen (growth) phase and 10% in the Catagen/Telogen phase. A normal head of hair consists of 100,000-150,000 hairs. If you are losing more than 100 hairs per day, this would be classified as excessive loss. Hair loss for six months is considered severe and may result in various forms of Alopecia, total or partial loss of scalp hair. The condition may be temporary or permanent. The hair's growth cycle is divided into three stages: 1) Anagen Stage The growing or active phase that varies for each individual, lasting 2-6 years, growing 1/4 - 1/2 an inch per month. 2) Catagen Stage The regressive or resting period where there is no growth activity. As soon as the growth phase is completed, degeneration of the hair follicle begins. This stage lasts 1-2 weeks. 3) Telogen Stage During this phase, which lasts 5-6 weeks, the hair is shed and a new one begins to replace the lost hair and reenters the Anagen phase. Regrowth will continue as long as the papilla stays active and a healthy condition continues to exist.   Daily hair loss is a natural biological occurrence. Normal hair loss may be between 50 - 100 hairs per day. At any given time 90% of a healthy head of hair should be in the Anagen (growth) phase and 10% in the Catagen/Telogen phase. A normal head of hair consists of 100,000-150,000 hairs. If you are losing more than 100 hairs per day, this would be classified as excessive loss. Hair loss for six months is considered severe and may result in various forms of Alopecia, total or partial loss of scalp hair. The condition may be temporary or permanent.   Factors Causing Hair Loss Androgen Alopecia - This is the most common type of hair loss responsible for 85-90% of all male and female temporary or permanent Alopecia. Androgen Alopecia probably occurs to a degree in all adults sometime after puberty. Androgens are hormones present in men and women. Normally higher levels are indicated in males. These hormones develop masculine characteristics. The onset of male & female excessive hair loss is inherited, and the growth of susceptible hair follicles is negatively affected. Thus resulting in temporary or permanent baldness. Testosterone is converted to a powerful destructive androgen hormone, Dihydrotestosterone (DHT) when it reacts with the enzyme 5-Alpha Reductase. Androgenic hair loss will not occur in men or women without the presence of DHT. DHT binds to the hair follicle and a progressive follicular miniaturization begins producing a shorter anagen cycle, increasing the number of telogen hairs. Male Androgenic Alopecia may begin anytime after puberty. Females may experience the condition as early as their mid twenties. Seborrheic Alopecia - A normal supply of sebum from the sebaceous glands is necessary to give hair its pliability and softness. Excessive sebum production may oxidize in the hair follicle and impair the hair's growth. Excessive sebum may produce an "androgenic ointment" containing DHT which can increase the tendency towards hair loss. This paste-like substance is an excellent breeding ground for bacteria and fungi. Alopecia Areata-- This type of hair loss that is indicated initially by small circular patches may progress to AIopecia Totalis where all of the hair on the scalp is lost. Alopecia Areata is usually associated with a deficiency in the immune system. A hypothyroid, other autoimmune diseases, and psychological problems may lead to this disorder. Telogen Effluvium Alopecia - This condition exists when more than 10% percent of the hair follicles progress to the Telogen (shedding) phase. Prolonged stressful situations, high fever, hormonal changes, and a wide variety of medications may contribute to this disorder. Telogen Effluvium normally occurs 3-6 months after childbirth and may last up to a year. Traction Alopecia - This type of hair loss often occurs as a result of hair styles and headwear that puts undue stress on a region of the scalp. Inadequate vascular circulation - A rich source of blood supply to the dermal papilla is essential for continued healthy hair growth. Blood is the source of nutrients and oxygen for hair cell production. During the Telogen phase, capillaries supplying essential growth elements to the hair follicle become inactive. Increasing microcirculation may lengthen the anagen (growth) phase producing longer, stronger & healthier hair. Nutritional Alopecia - Excessive hair loss is often observed in the malnourished. Deficiencies in zinc and iron, high intake of vitamin A, excessive dieting, or sudden weigh loss (bulimia or anorexia) often lead to this disorder. Dandruff, Psoriasis & Seborrheic Dermatitis - These are scalp disorders often associated with excessive hair loss. Trichotillomania If you pull out your hair, eyelashes, or eyebrows and have tried to stop but just can't, you are not alone!  You may suffer from trichotillomania.  For more information please visit their website at www.trich.org