💇 Hair Loss: Causes of Baldness, Types of Alopecia, and Ways to Strengthen Hair

Hair is an important part of appearance that affects self-esteem and self-confidence. Hair loss is a problem affecting millions of people worldwide. According to statistics, by the age of 50, about 50% of men and 25% of women experience noticeable hair thinning. However, hair loss is not a life sentence: understanding its causes and mechanisms makes it possible to choose effective strategies for preserving and restoring hair. It is important to distinguish normal hair renewal from a pathological process and to consult a specialist promptly.

Hair Structure and Growth Cycle

Each hair consists of two parts: the shaft (the visible part above the skin’s surface) and the follicle (the root located in the dermis). The follicle is a true “factory”: actively dividing matrix cells in its bulb produce keratin, the strong protein that hair is made of. The dermal papilla at the base of the follicle supplies nutrients through blood vessels.

Each follicle goes through recurring cycles:

• Anagen (active growth phase) lasts from 2 to 7 years. The longer the anagen phase, the longer the hair grows. At any given time, about 85–90% of scalp follicles are in this phase. The growth rate is approximately 1–1.5 cm per month.
• Catagen (transitional phase) lasts 2–3 weeks. Cell division stops, and the follicle shrinks, separating from the dermal papilla. About 1% of hairs are in this phase at any given time.
• Telogen (resting phase) lasts 3–4 months. The old hair is held loosely in the follicle and may fall out during brushing or washing. A new hair is already forming underneath it. It is normal for 10–15% of follicles to be in telogen.

Normally, a person loses 50–100 hairs per day. This is a natural renewal process. There is cause for concern when shedding increases noticeably, bald patches appear, partings become wider, or more hair than usual is left on the pillow or in the drain.

Types of Alopecia

Androgenetic Alopecia

The most common cause of hair loss, it accounts for more than 95% of cases in men and about 40% in women. It is caused by the genetic sensitivity of follicles to dihydrotestosterone (DHT), an active form of testosterone. Under the influence of DHT, follicles gradually shrink, or miniaturize: each new cycle produces a thinner and shorter hair until the follicle stops producing visible hair altogether.

In men, it follows a characteristic pattern: a receding hairline at the temples, thinning at the crown, and gradual expansion of the bald area. In women, it appears as diffuse thinning across the entire upper part of the scalp while the frontal hairline remains intact (Ludwig pattern).

Patchy Alopecia (Alopecia Areata)

An autoimmune disease in which the immune system mistakenly attacks hair follicles. It manifests as round or oval patches of complete hair loss that may appear suddenly. In mild cases, hair regrows on its own; in severe cases, hair loss may spread to the entire scalp (alopecia totalis) or the entire body (alopecia universalis).

Telogen Effluvium

Acute diffuse hair shedding that begins 2–4 months after a triggering event, such as a severe illness with a high fever, surgery, intense stress, childbirth, rapid weight loss, or discontinuation of hormonal contraceptives. A large number of follicles transition from anagen to telogen at the same time, and when the resting phase ends, all these hairs fall out at once. The process is usually reversible: hair density returns within 6–12 months if the cause is eliminated.

Traction Alopecia

Hair loss caused by constant tension from tight ponytails, braids, cornrows, extensions, or heavy hair clips. The hairline around the forehead and temples is most commonly affected. It is reversible in its early stages, but prolonged traction causes irreversible follicle damage.

Scarring Alopecia

A group of conditions in which follicles are destroyed and replaced by scar tissue. Causes include lupus erythematosus, scleroderma, folliculitis, burns, and injuries. Hair loss is irreversible, and treatment is aimed at preventing further spread.

Causes of Hair Loss: Hormones, Deficiencies, and Stress

Hormonal factors play a key role. In men, DHT is the main culprit. In women, the balance may be disrupted by changes in estrogen and progesterone levels: after childbirth (with postpartum shedding, up to 50% of hairs may enter telogen), during menopause, in polycystic ovary syndrome (PCOS), and with thyroid disorders, including both hypothyroidism and hyperthyroidism.

Nutrient deficiencies are a common but underestimated cause. Iron is essential for supplying follicles with oxygen: even a latent deficiency (ferritin below 30–40 ng/mL) can cause increased shedding. Zinc is involved in cell division and keratin synthesis. Vitamin D regulates the hair growth cycle, and its deficiency is associated with telogen effluvium and alopecia areata. Biotin (vitamin B7) is important for keratin structure, but an isolated deficiency is rare. Protein is the building material of hair: when protein intake is inadequate due to strict diets or poorly planned vegetarianism, the body “conserves” resources and shifts follicles into telogen.

Stress triggers telogen effluvium through a cascade of hormones: cortisol and adrenaline constrict blood vessels in the scalp, impair follicle nourishment, and prematurely shift follicles into telogen. A characteristic feature is that shedding begins not at the time of stress but 2–4 months later, when the person may already have forgotten the triggering event.

Diagnosis: When and Whom to Consult

A trichologist, a dermatologist specializing in hair disorders, is the main specialist for hair loss problems. Diagnosis includes:

• Examination and medical history — the pattern and duration of hair loss, triggering factors, family history, medications, and diet.
• Trichoscopy — examination of the scalp and hair under magnification using a dermatoscope. It allows assessment of follicle condition, hair thickness, and signs of miniaturization, inflammation, or scarring.
• Pull test — the doctor gently pulls on a bundle of 50–60 hairs. Loss of more than 10% indicates active shedding.
• Blood tests: a complete blood count with iron and ferritin, zinc, vitamin D, thyroid hormones (TSH and free T4); in women, testosterone, DHEA-S, and prolactin; and insulin if PCOS is suspected.
• Phototrichogram — a shaved area is photographed and hairs in the anagen and telogen phases are then counted, providing an objective assessment of shedding activity.

Diet and Supplements for Healthy Hair

A balanced diet is the foundation of healthy hair. Key nutrients include:

• Protein — the basis of keratin. Sources include meat, fish, eggs, legumes, and cottage cheese. An intake of 1–1.2 g per kilogram of body weight per day is recommended.
• Iron — red meat, liver, buckwheat, lentils, and spinach. Consume it with vitamin C for better absorption.
• Zinc — oysters, beef, pumpkin seeds, and cashews.
• Vitamin D — oily fish, egg yolks, and sunlight. Supplementation is often needed in northern latitudes.
• Omega-3 fatty acids — oily fish, flaxseed oil, and walnuts. They support scalp health.
• Biotin — eggs, nuts, and liver. Deficiency is rare with a balanced diet; supplements are effective only when a deficiency has been confirmed.

Important: “hair” supplements do not replace treatment and do not help with androgenetic alopecia. Taking supplements makes sense only when a specific nutrient deficiency has been confirmed by laboratory testing.

Scalp and Hair Care

Proper care will not cure alopecia, but it can help preserve existing hair and create favorable conditions for growth:

• Washing. Frequency depends on scalp type and can range from daily to twice a week. The myth that frequent washing increases hair loss is unsupported: hairs shed during washing are telogen hairs that would have fallen out anyway.
• Shampoo. Choose a gentle shampoo without harsh sulfates such as SLS that is suitable for your scalp type. For dandruff and seborrheic dermatitis, use products containing ketoconazole, zinc, or salicylic acid.
• Scalp massage improves microcirculation. A 2016 study found that a daily four-minute massage for 24 weeks increased hair thickness.
• Avoid damage: tight hairstyles, heat styling with high-temperature hair dryers, flat irons, or curling irons, as well as perms and harsh coloring, weaken the hair shaft and may damage follicles.
• Brushing: start at the ends and gradually work upward. Use a wide-toothed comb or a soft-bristled brush. Do not brush wet hair, as it is at its most vulnerable.

Seasonal Shedding and Other Factors

Many people notice increased shedding in autumn and spring. This is a normal seasonal renewal process: more follicles are in anagen during summer because greater exposure to light stimulates growth, while some transition to telogen by autumn. Seasonal shedding usually lasts 4–8 weeks and resolves on its own.

Other temporary factors include certain medications, such as antidepressants, beta-blockers, retinoids, and anticoagulants; discontinuation of oral contraceptives; anesthesia during surgery; high fever during illness; and extreme diets providing fewer than 1,000 kcal per day. In all these cases, hair loss is reversible once the cause is eliminated.

Psychological Impact

Hair loss can have a serious impact on psychological well-being. Studies show that up to 75% of people with alopecia experience a significant decline in self-esteem, while 40% have symptoms of anxiety and depression. Women generally find hair loss more distressing than men because thick hair is more strongly associated with attractiveness for them.

If hair loss is causing you serious psychological distress, do not hesitate to seek professional psychological support. Support groups, cognitive behavioral therapy, and a realistic perspective on the problem—alopecia is not dangerous to health—can significantly improve quality of life.

Hair Loss Myths

There are many misconceptions surrounding this topic. Wearing headwear does not cause baldness—a hat or cap does not cut off the blood supply to the follicles. Frequent washing does not increase hair loss; on the contrary, a dirty scalp may worsen follicle health. Shaving your head does not make hair grow back thicker or denser—this is an illusion caused by the blunt ends of newly growing hair. Cutting your hair does not stimulate growth—hair grows from the follicle, not from the tip. Male-pattern hair loss is not inherited only from the mother’s side—dozens of genes from both parents contribute to androgenetic alopecia.

At the first signs of increased hair loss, consult a trichologist. Early diagnosis and properly selected treatment can significantly slow the process and preserve hair density for many years.