Healthy, dense hair – who does not dream of it?? Hair loss hits especially women all the harder. What causes. Treatments are available?
Beautiful hair is associated with health, youthfulness, beauty, strength and higher social status in almost all societies and cultures. In addition, head hair protects from UV radiation and from the cold. No wonder that there are so many hairdressers – and an almost unmanageable selection of care products for hair. That is why a visible loss of hair frightens most people. But what is normal, and when is hair loss pathological??
Normal, daily hair loss
Who doesn't know this: After washing your cat's hair, you find a small ball of hair in the sink, shower or bathtub. Hair remains in brush and comb after combing. Depending on how often we wash, brush or comb our hair, we see more or less hair that has gone out.
How many hairs do you lose per day?
Up to 100 hairs a day in brush, comb or drain are normal. | Photo: © pixabay.com/eminens
Between 75.000 and 150.000 hair has each person normally on the head. Hair loss of up to 100 hairs per day is quite normal. But it is not necessary to count. Also normal is a decrease in hair density in women during pregnancy (temporary) and generally with age.
When do we speak of pathological hair loss??
But if you notice that the hair in certain places (such as the crown, top of the head, back of the head) grows back thinner or no longer grows at all, an examination by a doctor should take place. There are various examination methods that dermatologists use to determine whether there is pathological hair loss and which disease is the cause.
Stages of hair growth
Each hair has a growth phase of several years. It lasts on average 6 years. Then the life of a hair ends. The hair follicle from which the individual hair grows is being remodeled (catagen phase, 1 to 2 weeks). Subsequently, the hair follicle forms a new hair in depth. It grows and pushes the old hair out of the follicle and thus out of the scalp (telogen phase). This phase lasts 2 to 4 months until the old hair falls out.
The hairs are in different phases, therefore they do not all fall out at once. This usually ensures evenly dense hair growth.
Diagnostic possibilities at the doctor
Unnatural hair loss occurs when, due to internal or external influences, many hairs stop growing at the same time and too early. This results in increased hair loss after 2 to 4 months. So the event that led to the hair loss must have happened before these 2 to 4 months ago.
Medical history: In this typical collection of medical history, the doctor asks about events, illnesses and medication administration 2 to 4 months before the hair loss began, for example:
– When did the hair loss start? Has the hair loss increased or decreased since then, or has it remained the same? – Was there any physical stress such as a febrile illness or other serious illness 2 to 4 months beforehand? – Was there any severe psychological stress? – What medications were taken or injected? For example, it is known that heparin injections to prevent thrombosis can cause temporary hair loss – Hormonal fluctuations? In women, for example, discontinuation of hormone preparations ("pill"; hormones against skin diseases or against menopausal symptoms) or hormonal changes during pregnancy and after childbirth can lead to temporary hair loss – Thyroid dysfunction can also be the cause of hair loss – Do not be shocked if your doctor asks you if you have syphilis. This venereal disease causes hair loss – and the spread of syphilis is on the rise again
Diagnostics: First, the blood is often examined; this can be arranged by the family doctor. In-depth examination of scalp. Hair takes place at the specialist.
Blood test: Blood count, iron level (ferritin); thyroid hormones, inflammatory parameters; in younger women possibly also estrogens and androgens.
Viewing of the scalp: The general hair density is assessed and certain hair loss patterns are looked for, which can already be indicative of the diagnosis, such as circular hair loss, increased hair loss in the vertex area, etc. – The hair loss in the area of the hair follicle is examined. We also look for inflammations, scaling, scarring or infections in the scalp area. Photographs may also be taken – this allows for better assessment of progression later on.
Pull test: The doctor almost takes a small tuft of 20 to 30 hairs and pulls it. Normally, less than 20 % of the hair is detached in the process. If more than 40% of the hair falls out, it is unnatural.
Trichodermatoscopy: In this method, the scalp and the condition of the hair roots are examined with a microscope (dermatoscope), usually at 30x magnification.
trichogram: The doctor plucks ca. 50 hairs are lost, mostly from the affected scalp area and from an area with normal hair density. Then the doctor or an associate analyzes the hair roots microscopically. They will look in particular for the phase in which the hair is in. Normally, on average 85% of the hair is in the growth phase, 10 to 15% in the loss phase. In addition, it is examined how healthy the individual hairs and hair roots look. Often an additional sample biopsy of the scalp can be omitted.
Before a classic trichogram, the hair must not be washed for five days and must not be colored, tinted or permed for 14 days.
Digital trichogram: For some time now there is the computerized trichogram. In this method, the doctor, physician or a co-worker shaves off the hair on the head on an area about 2 cm small and inconspicuous. This area is stained and photographed immediately – or after three days; it depends on the ie. Depending on the phase, the hair then grows back. If there is too much hair in the resting or falling out phase, it is unnatural. The examination provides further information about the underlying cause of hair loss.
Advantages of this method are that neither hair must be plucked out, which can be somewhat painful, nor that the usual hair washing must be renounced as well as the digital photo documentation.
Common causes of hair loss
Increased general hair loss: Acute or chronic. Many things can be triggers: physical stress such as surgery, serious illnesses such as cancer, emotional stress, medications (heparin injections, chemotherapy, etc.).), hormone fluctuations, severe iron deficiency, and more. Examinations and therapy approaches are correspondingly diverse.
Androgenetic alopecia (AGA): In this hereditary hair loss, the hair follicles react sensitively to androgens (male hormones). Typical in affected men is the formation of forehead to full bald patches. Women also produce androgens in the body, but in much lower concentrations. About one in four women is affected to a greater or lesser extent by hereditary hair loss. In these cases, the area around the middle parting is typically thinned out. Approved and recognized therapies are minoxidil solutions for application to the scalp in different concentrations for women and men and finasteride for ingestion (only for men).
Circular hair loss (alopecia areata): Almost circular, completely hair-free areas are typical. These areas may be solitary or may merge together. In severe cases, the entire head is affected (alopecia totalis). If all body hair falls out, including eyebrows and eyelashes, it is called alopecia universalis. Circular hair loss is an autoimmune disease, but it does not destroy the hair follicles. Affected individuals more often develop other autoimmune diseases, such as autoimmune-related thyroid disease.
Often the disease heals spontaneously within 6 to 12 months, and the hair grows back normally again. But many sufferers also experience recurring episodes of circular hair loss afterwards. Neither are there any known triggers for the disease nor are there any therapies that are sure to work for all sufferers. Well-known and proven treatments include therapy with the immune stimulant diphencyprone (DCP) or immune-dampening corticosteroids. UV irradiation, possibly also zinc intake are also tried.
Anyone who notices increased hair loss should seek advice from a doctor. A good diagnosis helps very often to identify causes for hair loss and depending on that to get effective therapies.
Gabriele Wagner, Editor health& hair
Based on: Zenker, S.: Hair loss. aesthetic dermatology& cosmetology 2017; 3:31-3 Wolff, H.: Diagnosis and therapy of hair and scalp diseases. Dtsch Arztebl Int 2016; 113(21):377-86 Wolff, H.: Hope for hair loss.