Introduction
In technical terminology, hair loss is referred to as alopecia. In principle, it is completely normal that everyone loses hair and this every day. However, if the hair loss exceeds a limit of about 100 hairs per day, it is called pathological hair loss.
This can have various causes, mainly in the area of the: Synonyms in a broader sense: effluviums, hypotrichia, atrichia, alopecia
- Hormonally inherited hair loss (Alopecia androgenetica),
- Diffuse hair loss (Alopecia diffusa) and
- Circular hair loss (Alopecia areata).
With hair loss, there is an imbalance between naturally repelled and regrowing hair. This can have various causes. Diffuse hair loss is differentiated between hair that falls out during the growth phase (anagen effluvium) and hair that is already in the resting phase (telogen effluvium).
Anagen effluviums are rare and are caused, for example, by X-rays, chemotherapy or poisoning. Telogen effluviums occur more frequently and can have various causes, such as pregnancy, post-puberty, age, infections, diets, medication (beta blockers, lipid reducers, etc. ), vitamin deficiency, zinc deficiency, thyroid dysfunction.
Apart from particular diseases that require specific treatment, 90% of all hair loss is due to hereditary hair loss. This can be seen in both men and women. In the majority of hereditary cases, hair loss is caused by hormonal factors and is therefore also called androgenetic alopecia.
The hair becomes thinner and thinner, smaller and smaller, and eventually is almost invisible. Approximately every second man develops androgen-related hair loss during his lifetime. The near occurrence of hair loss in women increases significantly after menopause/menopause and affects 75% of women at the age of 65.
Due to the androgen hormone sensitivity of the scalp hair follicles, hair growth cycles become shorter and shorter. In about 10% of women, the genetic predisposition is so strong that they develop visible hair thinning around the age of twenty to thirty. Alopecia is aggravated by the hormonal changes during the menopause.
So-called circumscribed hair loss is clearly defined bald spots. Circular hair loss (Alopecia areata) is caused by a malfunction of the immune system. The hair follicles are attacked and the hair breaks off.
Other reasons for circumscribed alopecia areata are frequent wearing of elastic bands in the hair, wigs, wearing tight stockings and tight pants as well as bedriddenness. Scarring alopecia is caused by infections or skin diseases. Men are generally more often affected by hair loss than women.
In most cases, the above mentioned causes are the reason for alopecia. Hormonally inherited hair loss (Alopecia androgenetica) often affects very young men. The hair roots react particularly sensitively to dihydrotestosterone (DHT), which is a male sex hormone.
Although the hormone is produced normally and in physiological (healthy) quantities, the hair roots are particularly sensitive to it. The DHT is produced by an enzyme (5-alpha-reductase) from the male sex hormone testosterone. The hair roots of affected people also have this enzyme and so DHT is produced in large quantities.
This cause is genetic and is passed on to the offspring, not all offspring necessarily. Since the hormone DHT acts on the growth phase, the hair dies earlier. Gradually, the hairs become thinner and thinner until finally only a fuzz remains on the head.
This either remains or eventually falls out and no more hairs can be formed. Circular hair loss (Alopecia areata) has still largely unexplored causes. In medicine, it is assumed to be an autoimmune disease.
It forms round and oval bald spots, which are very sharply defined. Gradually, these areas can become larger and more and more bald spots can appear. These spots are completely hairless and at their edges there are always short broken hairs.
The preferred areas of Alopecia areata are on the sides and back of the head. Mostly young people and children are affected. Often the hair grows back again, but it often comes to relapses.
The loss of the entire scalp hair is also possible in the further course. More men than women are affected by this disease. The third, most common cause is diffuse hair loss (Alopecia diffusa).In diffuse hair loss, in contrast to circular hair loss, there are no specific areas, but the hair becomes thinner overall.
However, there is no hormonal cause. In addition to the thinning hair, one can also see the dulling of the hair, or the decrease in hair diameter. For this form of hair loss there are various possibilities, such as a normal aging process, medication, chemotherapy, radiotherapy, malnutrition, inflamed scalp, hormonal changes or even stress.
Androgenic alopecia is much less common in women compared to men. This can usually be seen from certain physical characteristics that women have a hormonal disorder that affects the male sex hormone testosterone, or dihydrotestosterone. These characteristics, which make the hormone disorder visible, are called increased hair on the upper lip, chin, nipples and bikini line.
In women, the causes of hair loss are generally similar to those of men (diffuse hair loss, hormonal and hereditary hair loss, and circular hair loss), but the causes are often complex and not clear. As already mentioned, in women it is very rarely a hormonal disorder that causes hair loss. Much more often, the cause is extreme stress, to which women are often exposed by the double burden of family and job.
In addition, malnutrition or the wrong diet is often the cause. During pregnancy and menopause, some women also suffer from hair loss because the body overacidifies. Due to the monthly bleeding, the acid-base balance can be kept very well in balance and many toxins in the body can be eliminated with the blood.
If the monthly bleeding stops, the body has to find other ways to help itself. Since the hair on the head is not very important for the body, only this area is “attacked”. The breeding ground for the hair simply overacidifies and the hair gets too few basic minerals and then eventually falls out.
In general, however, it is difficult to name individual causes, since there are usually several factors that influence and cause hair loss. As with men, however, drugs, radiotherapy, chemotherapy, an inflamed scalp, as a result of aging or hormonal changes can also be the cause of hair loss. The location of hair loss or thinning of the hair is different for women than for men.
In most cases, the hair begins to fall out and thinning at the crown of the head. Completely bald spots or even a bald head is hardly found in women. The phenomenon of circular hair loss is also rather rare.
