Hair loss: causes, types
& what you can do

More hair in the brush, a thinning parting or sudden round bald patches on the scalp: hair loss is extremely common, affects men and women alike, and can cause considerable distress – even though it is usually not medically dangerous. The good news: in many cases hair loss is reversible if the cause is identified and treated. Here you'll learn which types exist, which causes are typical, which treatments really work and why the right diagnosis makes the difference.

Table of contents

1. What you should do now
2. What's happening in the body?
3. Types and common causes
4. Hair loss in women vs. men
5. What really helps
6. Could it be your medication?
7. Warning signs: when to see a doctor?
8. Preparing for your doctor's appointment
9. How brite supports you
10. FAQ

For redness, scaling or scarring of the scalp, get a prompt dermatology assessment – scarring alopecia is irreversible!

1. What you should do now

2. Understanding hair loss – what happens in the body?

Everyone loses hair every day – up to about 100 a day is generally normal. Pathological hair loss (alopecia, effluvium) is when significantly more hair falls out than grows back, the hair visibly thins, or bald patches develop.

Hair loss can occur at any age, affects men and women, and has many different causes. In many cases it is reversible – provided the cause is identified and treated. The work-up starts with the question of which type it is: hereditary hair loss, diffuse thinning, round bald patches or scarring alopecia.

3. Types and common causes

3.1 Androgenetic alopecia (hereditary)

By far the most common form. In men: receding hairline, thinning crown, balding. In women: diffuse thinning around the parting, the frontal hairline usually stays intact. Genetically and hormonally driven – the hair follicles react with hypersensitivity to the hormone dihydrotestosterone (DHT).

3.2 Diffuse hair loss (telogen effluvium)

Even thinning of all the hair on the head. It usually appears two to three months after the trigger. Common causes:

• Iron deficiency – most common treatable cause, especially in women. Have ferritin measured.
• Underactive thyroid (Hashimoto's) or overactive thyroid – both can cause hair loss.
• Stress (physical and psychological) – after surgery, severe infection, mental crisis or crash diet.
• Medications – chemotherapy, retinoids, certain blood thinners, beta-blockers, lithium, antiepileptics.
• Nutritional deficiencies – zinc, biotin, vitamin D, protein deficiency.
• After infections – post-COVID hair loss is common and usually reversible.
• Hormonal changes – after childbirth (postpartum effluvium), menopause, PCOS, stopping the contraceptive pill.

3.3 Patchy hair loss (alopecia areata)

Sudden, sharply defined, round bald patches – usually on the scalp, less often in the beard area or on other parts of the body. An autoimmune disease: the immune system attacks the body's own hair follicles. In many cases the hair grows back spontaneously within months.

3.4 Scarring alopecia

Rare, but important: the hair follicles are permanently destroyed by inflammation or scarring. Recognisable by redness, scaling or visible scarring. Requires early dermatology assessment because the hair loss is irreversible.

4. Hair loss in women vs. men

Hair loss in men

The most common form is androgenetic alopecia – typical features are a receding hairline, thinning at the crown (tonsure) and eventually balding. It often starts as early as between 20 and 40. First-line treatment: topical minoxidil or finasteride (tablet, prescription only). The high level of psychological distress in men is often underestimated.

Hair loss in women

Androgenetic alopecia is also common in women but shows a different pattern: diffuse thinning around the parting, with the frontal hairline preserved. Iron deficiency is particularly common – women of childbearing age are often affected through menstruation, even without visible anaemia. Hormonal triggers: after childbirth (postpartum effluvium, usually between the 2nd and 4th month after delivery), when stopping the contraceptive pill, during menopause, with PCOS. Thyroid disorders are more common in women and often appear together with hair loss.

For women, topical minoxidil is approved – finasteride generally is not, as it is teratogenic. Anti-androgens or hormonal treatments can be useful in certain situations.

5. What really helps

Treatment for hereditary hair loss

Minoxidil (topical): The most widely used treatment. Available over the counter as a solution or foam. Must be used long-term – if stopped, the regrown hair usually falls out again. The effect sets in only after several months.

Finasteride (men): A prescription 5-alpha-reductase inhibitor in tablet form. It blocks the conversion of testosterone to DHT. Effective, but possible side effects (reduced libido, erectile dysfunction) need to be discussed with the practice.

Hair transplantation: A surgical option for stable findings (at least one year). The patient's own hair is transplanted from the back of the head to the bald areas. Reputable providers are experienced dermatology practices or university dermatology clinics.

Treatment for diffuse hair loss

Treatment depends on the cause: treat iron deficiency with iron supplementation (ferritin target well above the lower limit of normal), treat hypothyroidism with levothyroxine, switch or stop trigger medications in consultation with the practice. Plus: a balanced diet with protein, zinc, iron, vitamin D – and stress management. Patience: after the cause is removed, regrowth takes three to six months.

Treatment for patchy hair loss (alopecia areata)

Watchful waiting: For small, isolated patches the hair often grows back spontaneously.

Topical corticosteroids: Steroid solutions or creams can promote regrowth.

Intralesional steroid injections: Injected directly into the bald patches for limited involvement.

JAK inhibitors (e.g. baricitinib): Approved in the EU since 2022 for severe alopecia areata. They act on the misdirected immune system. For severe forms in adults.

Everyday life and care

Mild shampoo, don't blow-dry too hot, no aggressive styling products. Don't constantly tie the hair up (traction alopecia). Supplements (biotin, zinc, iron) only help with a proven deficiency – beware of overpriced hair vitamin products without evidence. For more severe or permanent hair loss, wigs are an option – the cost is usually covered by health insurance for alopecia areata totalis.

6. Could it be your medication?

Some medications can cause or worsen hair loss – others are the most important treatment options. An overview:

Other agents that can cause hair loss: retinoids (e.g. isotretinoin for acne), certain blood thinners, antidepressants and hormonal changes after stopping the contraceptive pill.

7. When should you have hair loss assessed?

• See a dermatologist quickly: Redness, scaling, itching or scarring on the scalp – suspected scarring alopecia (irreversible!).
• See a doctor promptly: Sudden round bald patches – suspected alopecia areata.
• See a doctor promptly: Markedly increased hair loss over several weeks or visibly thinning hair.
• See a doctor promptly: Hair loss with accompanying symptoms such as tiredness, sensitivity to cold or weight gain – suspected underactive thyroid.
• See a doctor promptly: Hair loss after starting a new medication.
• Hair loss in children.
• High level of psychological distress – patient organisations such as Alopecia Areata Deutschland e. V. offer support.

8. Preparing for your doctor's appointment – your checklist

• Since when? Weeks, months, years? Sudden or gradual?
• Where? Diffuse, around the parting, round patches, beard, eyebrows?
• Family: Is there hair loss in the family? Father, mother, siblings?
• Trigger? Stress, surgery, childbirth, diet, infection (including COVID), new medication?
• Accompanying symptoms: Tiredness, sensitivity to cold, weight changes, skin changes?
• Medications: Complete list – including over-the-counter products and supplements.
• For women: Periods regular? Stopped the contraceptive pill? Menopause?

More on this: Preparing for your doctor's appointment and Understanding your blood test results.

How brite supports you with hair loss

brite helps you organise your treatment and medication reliably – so you see long-term results instead of giving up frustrated.

• Medication reminder – Use iron supplements, levothyroxine, minoxidil and finasteride regularly: brite reminds you on time. Set up a reminder
• Interaction checker – Could one of your medications cause hair loss? Check interactions for free. Check now
• Digital medication plan – All medications clearly laid out for dermatology, endocrinology and your GP. Go to medication plan

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