Definition of hair loss
Basically, there are two forms of hair loss: effluviums and alopecia can be diffuse or circumscribed, scarring or non-scarring.
- Effluvium describes the loss of hair, which results in the loss of more than 100 hairs per day.
- Alopecia refers to the fact of hairlessness. This manifests itself in the form of bald spots or a baldness. If the hairlessness is congenital, it is called hypotrichia (partial) or atrichia (total).
General / Introduction
The daily hair loss is a physiological rejection reaction of the scalp of older hair. Therefore, a loss of about 100 hairs per day, which get caught in the brush or simply fall out when brushing, is completely normal. However, if the hair falls out in significantly greater numbers, various causes, such as congenital diseases, hormone influences or medication, can be responsible for this.
Epidemiology
A sparse hair growth or hair loss is not rare. Overall, however, significantly more men than women are affected. In Germany, approximately 1.5 million men and 500,000 women suffer from hair loss.
The hormonal hereditary hair loss (Alopecia androgenetica) is the most common form of hair loss with about 95%. About every second man suffers from this form of hair loss. Circular hair loss (Alopecia areata) is significantly less common.
About 1-2% of all people develop circular hair loss in the course of their lives. Usually, however, this begins in childhood or youth. The physiological hair cycle consists of 3 phases:
- In the growth phase (anagen phase) a new hair root is formed and the production of hair begins.
Depending on age and sex, the growth phase lasts from two to six years. 85-90% of the head hair is in this phase and is also called “papillary hair”.
- In the transition phase (catagen phase) the hair matrix stops its cell production and the hair follicle narrows in the lower area. The hair then separates from the papilla and atrophies.
In this phase, which lasts 2 to 3 weeks, there is about 1% of all hairs, which are then called “bed hairs”.
- The rejection phase (telogen phase) represents the final phase of the hair cycle. The atrophied hair falls out and the hair papilla and hair follicle regenerate. The matrix is formed again and begins to divide cells.
Thus, a new hair can be created. In this phase is about 18% of all hairs and it takes about 2 to 4 months. The hair is called “piston hair” in this phase.
The symptoms depend on the type of hair loss.
Anagen effluviums: The normally complete hair loss begins after about 14-20 days and is reversible in most cases. The hair roots of the fallen hair are conspicuously thin. Telogen effluviums: More than 100 hairs are lost per day.
When combing and washing the hair, the hair can be easily pulled out. Androgen effluviums begin with puberty, in men first in the form of so-called “receding hairline” and on the parting of the head, which gradually spread. Often one feels an itching.
In women, the front hair remains, only the hair on the parting falls out. Circular hair loss usually begins suddenly, with circular bald spots forming on the head or beard. Rarely, eyelashes and eyebrows can also fall out.
All articles in this series:
