Causes of hair loss


In the technical language one speaks of hair loss Alopecia. In principle, it is completely normal for everyone to lose hair every day.
However, if the hair loss exceeds a limit of around 100 hairs per day, it is referred to as pathological hair loss. This can have various causes, mainly in the area of:

  • hormonally hereditary hair loss (Androgenetic alopecia),
  • diffuse hair loss (Alopecia diffusa) and
  • circular hair loss (Alopecia areata) lie.

Synonyms in the broader sense:

Effluvia, hypotrichia, atrichia, alopecia
English: falling out of hair, lopecia

For more information, see the main article on Hair Loss.

Causes of hair loss

Male hair loss

In hair loss, there is an imbalance between naturally sloughed hair and hair that grows back. This can have different causes.

Diffuse hair loss

Diffuse hair loss distinguishes between hairs that fall out in the growth phase (Anagen effluvium) and hair that is already in the resting phase (Telogen effluvium).

Anagen effluvias are rare and result from x-rays, chemotherapy or poisoning, for example.

Telogen effluvia are more common and can have various causes, such as Pregnancy, post-puberty, age, infections, diets, medication (beta blockers, lipid lowering agents, etc.), vitamin deficiency, zinc deficiency, thyroid dysfunction.

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In addition to special diseases that require specific treatment, 90% of all hair loss is due to hereditary factors Hair loss. This is evident 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 designated. The hair becomes thinner and smaller and is ultimately almost invisible.

Around every second man will develop one in the course of his life Androgen conditional hair loss. The near onset of hair loss in women increases significantly after Menopause / menopause and affects 75% of women over the age of 65.

Due to the sensitivity of the scalp hair follicles to androgen hormones, the hair growth cycles become shorter and shorter.

In about 10% of women, the genetic predisposition is so strong that they develop a visible hair thinning around the age of twenty to thirty. Alopecia is aggravated by the hormonal changes during menopause.

Circumscribed hair loss

So-called circumscribed hair loss is clearly defined bald spots.

Of the circular hair loss (Alopecia areata) is caused by a malfunction of the Immune system. Here the hair follicles are attacked and the hair breaks off.

Other reasons for specific alopecia are frequent wearing of elastic bands in the hair, wigs, wearing of tight stockings and tight trousers, and being bedridden.

Scarring alopecia are caused by infections or Skin diseases.

Causes of hair loss in men

Different causes lead to hair loss in men

Men are usually more likely to be of Hair loss concerned than women.
Most of the above causes are the reason for the Alopecia. At the hormonally hereditary hair loss (Androgenetic alopecia) are often affected even very young men.

The hair roots are particularly sensitive to this D.iHydrotestosterone (DHT), which is a male sex hormone. The hormone becomes normal and in physiological (healthy) amounts are formed, but the hair roots are particularly sensitive to them. The DHT is made by an enzyme (5-alpha reductase) formed from the male sex hormone testosterone.
The hair roots of affected people also have this enzyme and so will DHT formed in large quantities. This cause is genetic and is passed on to the offspring, not necessarily all offspring.

Since the hormone DHT acts on the growth phase, the hair dies earlier. Little by little the hair becomes thinner and thinner until finally only a fluff remains on the head. This then either persists or ultimately falls out and hair can no longer be formed.

Circular hair loss (Alopecia areata) has so far largely unexplored causes. In medicine it is assumed that there is a autoimmune disease is. Round and oval bald spots are formed that are very sharply defined. Gradually, these areas can enlarge and more and more bald spots can appear.
These areas are completely hairless and you can always find short, broken hair on the edge. The favorite spots of the Alopecia areata are on the sides and back of the head. Usually adolescents and children are affected. Often the hair grows back, but relapses often occur. The loss of the entire head hair is also possible in the further course. More men than women are affected by this condition.

The third, the most common cause is the diffuse hair loss (Alopecia diffusa). With diffuse hair loss, contrary to circular hair loss, there are no specific areas but the hair becomes thinner overall. But there is no hormonal cause. In addition to the thinning hair, you can also see the duller overall, or the decrease in the hair diameter. There are several options for this form of hair loss, like normal Signs of aging, Taking medication, Chemotherapy, radiation therapy, malnutrition, inflamed scalp, hormonal changes or even stress.

Causes of hair loss in women

As with men, hair loss in women has different causes.

Androgenic alopecia is much rarer in women compared to men.
You can usually see this in certain physical characteristics that women have a hormone disorder, the male sex hormone testosterone, or. Dihydrotestosterone concerns. These features that make the hormonal disorder visible are called one increased hair on the Upper lip, at the chin, to the Nipples and in the Bikini line.

In women one can generally name similar causes as in men for hair loss (diffuse hair loss, hormonally hereditary hair loss and circular hair loss), but the uses are often very complex and not clearly clear. As already mentioned, it is very rarely a hormonal disorder that causes hair loss in women.
Much more often the cause is more extreme stress, to which women are often exposed due to the double burden of family and work. In addition, there is often malnutrition or poor nutrition.

During the pregnancy and the menopause hair loss also occurs in some women because the body is acidic.
Through the monthly bleeding, the acid-base balance can be kept very well in balance and many toxins in the body can be excreted with the blood. If the monthly bleeding stops, the body has to help itself in other ways.

Since the head hair is not particularly important for the body, this area is first “attacked”.
The breeding ground for the hair is simply acidic and the hair does not get enough basic minerals and then eventually fall out.

In general, however, it is difficult to name individual causes, as there are usually a few factors that influence and cause hair loss.
As with men, but also can Medication, radiotherapy, chemotherapy, an inflamed scalp, as a result of aging or hormonal changes can be the cause of hair loss.

The location of the hair loss or thinning of the hair is different in women than in men. In the case of female hair loss, the hair usually only begins to fall out and thin out at the crown. Completely bald spots or even a bald head are rarely found in women.
The phenomenon of circular hair loss is also rather rare.

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The cause of childhood hair loss

Even with children Hair loss have multiple causes.
Just by using Hair tiesthat are not necessarily suitable, or other hair accessories or if the hair ties are tied too tightly together over a long period of time, the hair can be damaged. Typically, the hair near the forehead and on the side of the head falls out.
The hair usually grows back by itself within a short time. The type of hair loss is referred to as Traction hair loss. Some children also cannot tolerate certain shampoos, which then causes hair loss. In children, just as in adults, sometimes the circular hair loss occurs (Alopecia areata), the cause of which has not yet been really explored. However, it is believed that the cause is an autoimmune disease in which the hair follicles are suddenly attacked and the hair then falls out.

Another is one Fungal infection. They are called in technical jargon Tinea capitis. It affects the scalp. These infections are completely harmless, but very unpleasant. Unfortunately, this fungal infection can easily be passed on from one person to the next using, for example, common brushes or hair accessories. A very serious cause of hair loss is genetic Menkes syndromewhich affects babies. It is inherited in an x-linked recessive manner and therefore only affects boys. The children affected suffer from an enormous copper deficiency in their blood, liver and brain.
At first the children have completely normal head hair. Gradually, however, it becomes thinner, lighter and more brittle and looks like very fine steel wool. Another cause is that Netherton Syndrome. It is inherited in an autosomal recessive manner and affects girls more often than boys. This condition affects all body hair and makes the hair dull and brittle. The hair has an increased hair shaft fragility and you can only bring about relief with medication.

Hair shaft anomalies are also common in young children.

Hair loss from chemotherapy

At a chemotherapy are so-called Cytostatics take advantage of the rapid cell division of cancer cells and attack there.
These cytostatics cannot differentiate between sick and healthy cells, but generally attack all cells that divide quickly. In addition to the cells in the gastrointestinal tract in the mucous membrane, this affects the blood cells and also the hair cells.
Hair growth is interrupted and the hair becomes thinner and more fragile. At some point they simply break loose from their anchorage. Hair usually grows about about a day 0.3 mm and approx. 85% of the hair cells are constantly in the cell division phase. Sometimes the hair loss affects not only the scalp hair, but also Eyebrows fall out, Eyelashes and the rest of the body hair.