Hair Loss Guide (2025)

Over 80% of men and over 25% of women suffer from hair loss. The majority of those affected suffer from pattern baldness. But what are the causes? And what can be done to fight hair loss?
Use this page to discover the truth behind hair loss and what effective treatment options are available.

The majority of people will be affected by hair loss at some point in their lives with the most common cause being  pattern baldness, also known as androgenetic alopecia (AGA). According to our hair loss statistics 85% of men and 33% of women will experience AGA at some point in their lifes. It can affect hair all over the body or just on the head.

Older people are most commonly affected by hair loss. It is normal to lose fifty to one hundred hairs a day, which is a manageable, inconspicuous amount when there are over one hundred thousand hairs on the head.

Usually, new hair grows back to replace the lost hair, but  this is not always the case. Hair loss can take many different courses. It can occur suddenly or increase slowly over the years.

If you notice that you are losing more hair than usual, you should consult your doctor. They can find the reason behind the hair loss and inform you of potential treatment options.

Generally, hair growth is divided into three phases, the growth phase (anagen phase), the transition phase (catagen phase) and the resting or loss phase (telogen effluvium phase).

The growth phase contains about 85% of all hairs in the head. This phase lasts about two to six years and describes the time in which the hair actively grows, becoming longer and thicker.

The hair undergoes a “rebuilding process” in the transition phase. Here the cell division comes to a standstill and the hair root is no longer supplied with nutrients, so it starts to shrink. This phase usually lasts about two weeks and ends when the root is keratinized and  ready for the final phase, the loss phase. In this phase, the metabolic activity of the hair follicle is stopped, which causes the hair to die and fall out.

This process affects about 8% to 14% of the hair on the head for roughly three months, until the hair matrix forms new hair. The hair then falls out because the regrowing hair pushes the old hair out of the follicle. The hair cycle starts again with the growth phase.

Male patten hair loss

Hereditary hair loss, also called androgenetic alopecia and male pattern hair loss, is one of the most common forms of hair loss in men. Also known as hereditary or hormonal hair loss, it is usually a gradual process.

 

The risk increases with age, so that by the age of 70, nearly 80% of men are affected. The predisposition is inherited from both parents, although the influence of the maternal side is probably stronger.

This form of hair loss can be characterized by the thinning hair in the forehead area initially with a receding hairline. The hairline will then continue to recede, leaving behind large bald spots on either side of the forehead.

Further along in the course of this disease, the hair at the back of the head (crown) also becomes visibly thinner, so that the affected areas slowly spread over the years. In addition, a tonsure, a bald spot on the crown of the head, can develop. The degree of male pattern hair loss is typically described by the norwood scale. According to our hair transplant statistics most of the patients have a medium hair loss degree (NW4)

One of the most common causes is a predisposition to hypersensitivity of the hair follicles. These react sensitively to the breakdown product of the male hormone testosterone DHT (5-alpha-dihydrotestosterone).

 

Female pattern baldness

Hereditary hair loss, also known as androgenetic alopecia, can occur in women as well.

Even though women are less affected, this form of hair loss is still widespread. Currently 21 million women in the US and 8 million women in the UK suffer from some form of hair loss. In women, the hair at the crown of the head becomes thinner and lighter.

From the age of 30,  congenital hair loss in women can begin insidiously. However, the thinning of hair is most often noticed during menopause.The hair roots are inherently sensitive and react to the hormonal changes that occur during menopause.

Especially in the hair part, the scalp becomes more visible,though complete baldness in women is rather unlikely and very rare. In the case of hair loss caused by androgenetic alopecia, the usual remedies such as shampoo or a change in diet unfortunately cannot help.

Alopecia Areata

Circular hair loss, also known as alopecia areata, is one of the most common inflammatory hair loss diseases.This form of hair loss often occurs in episodes and displayssymptoms such as pain in the affected area or itching.

The causes of alopecia areata have not yet been fully realized. There is neither an age-related nor a gender-specific correlation, it can affect anyone, whether young or old,  man or woman.

However, there are some known factors which have relevance in the development of the disease. First and foremost, among these is a disorder of the immune system.

Consequently, a local inflammatory reaction occurs, which limits hair growth and leads to hair loss. The bald, round spots are mostly found on the head, but can also occur in other parts of the body such as eyebrows or beard.

Genetic predisposition also plays a role in the course of the disease. Circular hair loss  occurs more frequently in families.

In addition, this form of hair loss can, in some cases, also be attributed to high levels of stress. For example, circular hair loss can occur  after accidents or bereavements.This form of hair loss is also the result of malnutrition or harmful environmental influences.

The most severe form of circular hair loss can affect the whole body and is also known as ‘Alopecia areata universalis’.

 

Diffuse hair loss

Diffuse hair loss does not affect a specific area of the head, but thins the hair altogether. It is usually only noticed by those affected roughly four months after the causative event.

Usually, the increased hair loss is finally noticed when combing or washing the hair and the scalp becomes more visible through the thinning hair.

This form of increased hair loss can have several, very different causes. These can range from illnesses such as malfunctioning of the thyroid gland, infectious diseases, a diet with vitamin deficiency, to acute stress situations, hormonal changes or taking medication.

The following causes can play a role in diffuse hair loss:

 

Diseases

The following diseases can lead to diffuse hair loss:

• Disturbed thyroid gland function such as hypothyroidism or – Overactive thyroid
• Infectious Diseases
• Venereal diseases like syphilis (lues)
• Chronic intestinal diseases like ulcerative colitis and Crohn’s disease
• Cancer diseases
• Eating disorders like bulimia and anorexia
• Diabetes mellitus
• Systemic lupus erythematosus (SLE)

 

Drugs

Taking the following medications can lead to diffuse hair loss:

• Chemotherapy with cytostatic drugs
• Painkillers (analgesics)
• ACE inhibitors and beta blockers e.g. for high blood pressure
• Lipid reducers
• Retinoids
• Thyroid medication
• Heparin (blood thinner)
• Antibiotics

 

Radiotherapy and radiation accidents

Diffuse hair loss can be caused by radiotherapy or radiation accidents.

• Hair loss is caused by ionizing radiation (3.8 Gray).
• After about two months, the hair usually grows back.
• A radiation dose above 8 Gray can lead to permanent hair loss.

 

External circumstances

Diffuse hair loss can be caused by external circumstances.

• Extraordinary stress
• Surgery, general anesthesia

 

Hormonal changes

Diffuse hair loss can be related to hormonal changes.

• Develops in some women about two to four months after the birth of a child. The reason for this is an estrogen deficiency, as the concentration of this hormone drops after delivery, and excess hair produced during pregnancy falls out. Stress during childbirth can also promote hair loss.
• Taking or discontinuing medication for contraception (e.g. the pill)

Menopause, particularly in the beginning

 

Nutrition

Malnutrition can lead to diffuse hair loss.

• One-sided, unhealthy nutrition
• Radical diets
• protein or iron deficiency
• vitamin, biotin or zinc deficiency, occurs rather rarely