Hair Life Cycle 

 

Hair loss is a very common issue that affects almost everyone at some stage of their life. It is more frequently seen in males, generally starting from the age of 25 until the age of 50 and it affects approximately 70% of all men at some stage of their lives.

The rate of hair loss differs from one individual to the other; it tends to begin with receding of the hair line above the forehead, together with thinning of the hair at the front and top. In time, hair
loss can extend over the top of the head. This loss of hair, which in many individuals constitutes
the most important part of their external appearance, may cause both physical and psychological issues for the individual.

The growth cycle of hair consists of three phases which are called anagen, catagen and telogen. The active growth period (anagen phase) is followed by a short recession (catagen phase) which immediately gives way to the resting period (telogen phase). Hair that reaches the end of its life i
s shed and healthy new hair grows in its place. Within this growth cycle, daily loss of about 100 hairs is considered normal.

 

Hair Loss

 

Hair loss is a common issue in both males and females but more frequently observed in men. It has been found that between the age of 25-50, that 25-50% of males experience hair loss. Before the hair loss treatment, it is suggested that the type of hair loss must be examined by a dermatologist because it may cause from hormonal, metabolic or nutritional effects; without their solution, %100 therapy is never possible. Hair loss could be separated into two parts as hereditary and temporary.

 

Common Causes of Hair loss

 

  • Stress
  • Exhaustion
  • Malnutrition
  • Illness
  • Some medicines
  • Hormonal Problems
  • Genetic Predisposition
  • Air Pollution

 

 

Temporary Hair Loss

Not all types of hair loss are permanent. Hair loss takes place in connection with varying physiological or psychological conditions, as exemplified below:

1. Regular hair loss
Normally, the hair that completes its growth cycle, loses its connection with the follicle in the telogen phase and sheds. A daily loss of up to 100 hairs is considered normal by dermatologists. Exceeding numbers of hair shed is likely to refer to a “hair loss problem”.

2. Hair loss related to pregnancy and child birth
In pregnancies, as a result of decreasing enzyme levels and hormonal imbalance, follicle transits to a slowing-down phase, development of hair stops and hair sheds faster than normal. Hair loss most likely stops about 6 months after the delivery and/or when the hormonal balance is restored.

3. Heavy Stress
Severe emotional disorders (such as psychological impacts of death of a close relative, break-ups, job loss, etc.) may lead to hair loss problems (mostly referred as telogen effluvium).
In this case, excessive amounts of hair switch from active (growth phase) to telogen (resting phase) and shed afterwards.

Telogen effluvium is more common amongst women. Pure telogen effluvium is reversible, still hair regrowth can take up to six months, usually following the elimination of stress factors.

4. Alopecia areata 
Also known as pelade, it is a temporary hair loss problem observed as hair loss in circular areas with a radius of 2-2,5cm.  It is not related to age or gender. It develops as a result of decreased body resistance usually caused by long term stress. Hair re grows after body resistance is restored though some areas of scalp may be left with bald spots.

5. Hair loss related to misuse of cosmetic products
The synthetic materials used in cosmetic products or their misuse may cause allergy and irritation on the scalp which then may lead to hair loss. Problems may also occur because of hair dyes, hair stylers and wrong shampoo choice that is not suitable to the hair type.

6. Hair loss related to high fever
Long term high fever may refer to post-febrile alopecia. This type of hair loss that is observed 4-6 weeks after high fever. After the recovery, the hair growth cycle is restored.

7. Hair loss related to medications 
Some medications (especially blood thinners, antidepressants, birth control pills, antihypertensives, high dose vitamin A etc.) especially used in long term treatments may affect the hair follicles and cause hair loss (Diffuse Alopecia).

8. Hair loss related to severe illnesses 
Especially genetic and hormonal illnesses as well as HIV, Lichen planus, folliculitis may also be the reason of temporary hair loss.

9. Hair loss related to malnutrition
Nutritional deficiencies may lead to increase hair shedding, weakened hair shafts or slower regrowth. Hair loss is more likely among individuals whose diet lacks of essential nutrients – mainly protein, vitamins and minerals (principally iron, zinc and sulphur; as well as group B vitamins).

Hereditary Hair Loss (Male Pattern Baldness)

Hereditary hair loss refers to the process, where the male hormone shortens the hair –growth – cycle, causing miniaturization of the follicles, and producing progressively finer hairs and usually ends up with hair – loss.  This type of hair loss is characterized by receding hairline first in the forehead and temple area, and then bald spots on the crown are seen.

Androgenetic Alopecia

It is the condition, caused by the male hormone, testosterone. It is characterized by receding hairline beginning at the forehead followed by some bald spots due to thinning hair on the top of the head in genetically inherited post pubertal individuals generally aged 20 – 30. Also called male pattern baldness, it can be seen on most of the scalp, but on temporal area and nape.

Although in different levels, since the male hormone is present in women as well, they can be subject to hereditary hair loss, still in different patterns.

Androgenetic alopecia should not be classified as a disease (though Alopecia areata is – see Temporary Hair Loss), as it does not impose any physical restriction on individual’s activity, but rather possible emotional disorder. Research suggests that frontal recession on the hair line occurs in 95% of Caucasian men and they have a 70% incidence of androgenetic alopecia (male pattern hair loss) during their lifetime.

 

Key factors for male pattern hair loss other than hereditary tendency are :

 

1. Age

Decreasing resilience of hairs

2. Hormones
Testosterone, a male hormone (androgen), is converted to DHT (Dihydrotestosterone). DHT causes gradual miniaturization of the hair follicle. Miniaturized hair follicles then produce thinner and less resilient hairs and they are over time atrophied; the explicit result is hair loss.

3. 5α-reductase
The enzyme called 5-alpha-reductase catalyzes the conversion of Testosterone to DHT (the enzyme binds with testosterone and transforms it to DHT). The increased level of 5α-reductase activity means more prominent DHT and consequently miniaturized hair follicles and thinned hairs.

After the DHT level on hair follicles is reduced, the miniaturization effect is eliminated and hair re growth from non atrophied follicles is reinforced.