alopecia: Definition from Answers.com

Definition

Alopecia is the partial or complete loss of hair—especially on the scalp—either in patches (alopecia areata), on the entire head (alopecia totalis), or over the entire body (alopecia universalis).

Description

A basic understanding of hair biology and normal hair development is essential in distinguishing normal versus abnormal hair loss in children and adolescents.

Hair consists of the shaft and the root, which is anchored into a follicle beneath the epidermis. Hair is formed by rapid divisions of cells at the base of the follicle. Except for a few growing cells at the base of the root, hair, which is composed of keratin and other proteins, is dead tissue.

An individual hair follicle has a long growth phase, producing steadily growing hair for two to six years. About 80 percent to 90 percent of hair follicles are involved in this active growing period called the anagen phase. Next is a brief transitional phase (of about three weeks' duration)—the catagen phase—during which the hair follicle degenerates. About 5 percent of follicles are involved in the catagen phase.

Then a dormant period known as the telogen phase occurs. About 10 percent to 15 percent of hairs are involved in this phase, which lasts for approximately three months. Following the telogen phase, the growth phase begins again, and the growth cycle repeats.

Each person has about 100,000 hairs on their scalp. Although it is normal to lose between 25 and 100 hairs per day, any disruption of the hair growth cycle may cause abnormal hair loss.

Demographics

It is estimated that alopecia affects several million children in the United States and that hair loss is responsible for about 3 percent of all pediatric office visits.

Alopecia areata affects both sexes and all ages but is most common in children five to 12 years old. About one per 1000 children has alopecia areata. Approximately 5 percent of children with alopecia areata go on to develop alopecia totalis, and some of these children may develop alopecia universalis.

Tinea capitis (ringworm) affects an estimated 10 percent to 20 percent of susceptible children, and although the demographics are sketchy, telogen effluvium is the most common type of alopecia in both children and adults.

Causes and Symptoms

Although in children and adolescents, hair loss may be caused by a wide variety of factors, most children experience hair loss as a result of one of four major causes:

fungal infections
alopecia areata
trauma to the hair shaft
telogen effluvium

A fungal infection called tinea capitis, which is similar to athlete's foot, is a common cause of hair loss, particularly among toddlers and early school-aged children. Tinea capitis, which affects the hair root, is a highly contagious condition and is often transmitted when a child uses the comb, brush, hat, or bed linen of an infected child. Tinea capitis seldom occurs after puberty.

Children with this condition usually have patchy hair loss with some broken hairs visible just above the surface of the scalp. The patches of hair loss are usually round or oval but are sometimes irregular in shape. When broken off at the surface, the hairs resemble small black dots on the scalp. Occasionally gray flakes or scales are present.

Alopecia areata, or localized baldness, is the sudden appearance of sharply defined circular or oval patches of hair loss, most often on the scalp. These patches are smooth and without inflammation, scaling, or broken hairs and may appear overnight or over the course of a few days. This condition may affect scalp hair, the eyebrows, eyelashes, genital area, and occasionally the underarms. The hair loss is not accompanied by other visible evidence of scalp disease, and the condition is not contagious.

In alopecia areata, immune system cells (white blood cells) attack the rapidly growing cells in the hair follicles that produce hair. The affected hair follicles decrease in size and hair production slows drastically. Because the stem cells that continually supply the follicles with new cells do not appear to be affected, the follicle retains the potential to regrow hair.

Although it is uncertain why the hair follicles undergo these changes, it is thought that a combination of genes may predispose some children and adults to the disease. In those who are genetically predisposed, some type of trigger—perhaps a virus or something in the child's environment—brings on the attack against the hair follicles.

Trauma to the hair shaft is another common cause of hair loss in children. Often the trauma is caused by traction resulting from, for example, tight braids, ponytails, or by friction (hats, hair bands, or rubbing against a bed). Trauma may also be caused by chemicals or burns.

Another important cause of hair trauma is called trichotillomania—a habit similar to thumb-sucking or nail-biting—of twirling or pulling out the hair. Trichotillomania is generally considered to be a nervous habit and may include the pulling of eyebrows and eyelashes.

The hair loss associated with trichotillomania is patchy and is characterized by broken hairs of varying length. Within the patches, hair loss is not complete. If the hair trauma is not severe or chronic enough to cause scarring, the child's hair usually regrows when the trauma ceases.

Telogen effluvium, another common cause of hair loss, affects both children and adults. This condition is responsible for more hair loss than any other cause except adult male-pattern baldness. In telogen effluvium, there is a physiologic basis to the hair loss; something happens to interrupt the hair's normal growth cycle and to drive many or all of the hairs into the telogen phase. Between six and 16 weeks later, partial or complete baldness occurs.

Many factors can cause telogen effluvium, including the following:

high fever
medications, including chemotherapy
crash diets
excessive vitamin A
emotional stress
surgery
severe injury

In the telogen phase, a child's hair undergoes growth spurts and pauses. During the rest phase between spurts, the bulb at the end of the hair root decreases in volume and the hair loosens. Although exaggerated during adolescence, particularly in girls (due the influence of female hormones), even preadolescents may experience excessive hair loss on a daily basis. The scalp hair, however, appears normal in this condition.

When to Call the Doctor

It is important to consult a dermatologist or pediatrician if a child sheds hair in large amounts (more than 100 hairs per day for longer than four weeks) after combing, brushing, or shampooing or if the hair becomes significantly thinner. Also, if a child's scalp show signs of infection (redness, swelling, tenderness, warmth), consulting a physician is advised.

If children are observed pulling out their hair, eyelashes, or eyebrows, parents should consult a physician in order to determine the underlying cause of the habit.

Diagnosis

Because hair loss is caused by a variety of conditions, a physician diagnoses the cause of the child's hair loss based on medical history, family history of hair loss, medications (including vitamins), nutritional status, hair-care habits, and a physical examination.

If the physician suspects a fungal infection of the scalp, a hair sample may be tested by microscopic examination in the laboratory. Microscopic examination of a hair plucked at the periphery of the hair loss area often reveals a characteristic disruption of the integrity of the hair shaft. The infection may be confirmed by culturing the scalp for fungal organisms.

Blood tests or a scalp biopsy may be required if a medical condition—such as lupus erythematosus, thyroid dysfunction, iron deficiency, or hormonal imbalance—is suspected.

Treatment

Treatment varies with the cause of the hair loss. In some cases, early treatment is important in restoring the hair. Often congenital and hereditary hair loss and hair shaft abnormalities, however, have no effective treatment.

For fungal infections such as tinea capitis, treatment usually requires a systemic approach with an oral anti-fungal prescription medication such as griseofulvin (Fulvicin). This medication, which must be taken for four to eight weeks, is very effective in curing the infection and restoring the hair. Early treatment is important in preventing possible permanent hair loss.

Topical creams or antifungal shampoos containing 2 percent ketoconazole are often used two to three times per week for eight weeks. Although shampoos and topical antifungal creams may decrease scaling, the infection usually returns because these products do not penetrate the hair follicle deeply enough to eradicate the infection.

A wide variety of treatments are available for alopecia areata. There has been some success with use of medications that suppress the immune system, including dinitrochlorobenzene (DNCB) and diphenylcycloprope-none (DPCP). The side effects of these drugs, however, may outweigh the benefits for a disease that most often resolves on its own.

In addition, topical creams or lotions such as minoxidil, cortisone (also injected into the scalp), or anthralin are sometimes used. Because such treatment triggers hair growth in bald patches but does not eradicate the disease, however, new bald patches can occur in other parts of the scalp even if new growth occurs.

Hair loss resulting from telogen effluvium or drug side effects usually requires no treatment. Hair loss from poor nutrition or medical illness usually stops with the adoption of a healthy diet and treatment of the underlying medical condition. Once the stressful event is over, complete hair growth usually occurs within six months.

Alternative Treatment

There is some evidence to suggest that aromatherapy is a safe and effective treatment for alopecia areata. Aromatherapy involves rubbing scented essential oils into the skin to treat localized and systemic disease.

Massaging the essential oils of rosemary, lavender, sage, thyme, and cedar into the scalp is believed to increase circulation and reduce stress. About three to six drops of essential oil are added to 1 tablespoon of jojoba or grape seed oil and massaged into the scalp.

In addition to aromatherapy, stress reduction techniques such as yoga, meditation, or creative visualization may increase blood flow to the scalp and stimulate hair growth.

Prognosis

The prognosis for children with alopecia varies with the cause of hair loss. Certain types of alopecia respond more readily to treatment. For example, hair loss in telogen effluvium usually occurs over several weeks to months, then stops. Hair then grows back over the next several months.

Overall, the outlook for children with alopecia areata is good. Alopecia areata usually resolves with time, although alopecia totalis is less likely to remit. With appropriate treatment, from 60 percent to 95 percent of children regrow all of their hair within one year.

Early treatment and the proper antifungal medications can cure tinea capitis, although patience is required because the condition may take several months to resolve.

Prevention

Although it may not be possible to prevent all types of alopecia—such as alopecia areata or hair loss associated with medical conditions—certain forms of hair loss may be prevented. Highly contagious fungal infections such as tinea capitis, for example, may be prevented by keeping hair clean and by teaching children not to share hats, combs, or hair brushes. In addition, adolescent girls should be cautioned not to share makeup.

It is important to teach children and adolescents to handle their hair with care, especially when shampooing, drying, brushing, combing, braiding, and using chemical processes. Hair is more fragile when it is wet, so vigorous towel drying and rough combing and brushing should be avoided. Wide-toothed combs and brushes with smooth tips are recommended.

Nutritional Concerns

Children may experience hair loss or excessive thinning as a result of certain nutritional deficiencies. To prevent such hair loss, it is essential to include B-6, biotin, and folic acid—either in the diet or in supplement form.

It has been found that certain minerals, including magnesium, sulfur, silica, and zinc are also important for maintaining healthy hair. Beta-carotene, which is converted to vitamin A in the body, is also essential to healthy skin, hair, and nails. Beta-carotene is found in green and yellow vegetables and fruits.

Because hair is composed of protein, a diet that is too low in protein may cause hair thinning or a disruption of the growth cycle. Thus eating a protein-rich diet often results in improved hair growth. In addition to lean meat, good food sources of protein include fish, eggs, dairy products, and beans.

Parental Concerns

Because society has placed so much emphasis on appearance, hair loss, particularly if it is severe, may be emotionally devastating to children and adolescents. Hair loss can lead to embarrassment, low self-esteem, and depression. Thus it is important for parents to consult a physician as soon as possible to minimize not only the physical but also the emotional impact of hair loss on their child.

Resources

Books

"Disorders of Hair." In Nelson Textbook of Pediatrics, 17th ed. Edited by Richard E. Behrman, Robert M. Kliegman, and Hal B. Jenson. Philadelphia: Saunders, 2004.

Powell, Jennifer, Natalie Stone, and Rodney P. R. Dawber. An Atlas of Hair and Scalp Diseases. Carnforth, UK: Parthenon, 2000.

Periodicals

Usatine, Richard P. "Bald Spots on a Young Girl." Journal of Family Practice 53, no. 1 (January 2004): 33–36.

Organizations

American Academy of Dermatology. PO Box 4014, Schaumburg, IL 60168–0050. Web site: www.aad.org.

American Hair Loss Council. 125 Seventh Street, Suite 625, Pittsburgh, PA 15222. Web site: www.ahlc.org.

National Alopecia Areata Foundation. PO Box 150760, San Rafael, CA 94915–0760. Web site: .

Web Sites

Brodell, Robert T., and Giorgio Vescera. "Black Dot Tinea Capitis." Postgraduate Medicine Online 111, no. 4 (April 2002). Available online at www.postgraduatemedicine.com/issues/2002/04_02/pd_brodell.htm (accessed October 10, 2004).

[Article by: Genevieve Slomski, Ph.D.]

"Bald" redirects here. For other uses, see Bald (disambiguation).

Alopecia
Classification and external resources
Man displaying male pattern baldness
ICD-10	L 65.9
ICD-9	704.0
DiseasesDB	14765
MeSH	D000505

Baldness implies partial or complete lack of hair. Balding is part of the wider topic of "hair thinning". The degree and pattern of baldness can vary greatly, but its most common cause is male and female pattern baldness, also known as androgenic alopecia, alopecia androgenetica or alopecia seborrheica – an alternative term used primarily in Europe.

Pattern balding should not be confused with alopecia areata, which commonly involves patchy hair loss. Extreme forms of alopecia areata are alopecia totalis, which involves the loss of all head hair, and the most extreme form, alopecia universalis, which involves the loss of all hair from the head and the body.

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Cause

More than 95% of hair thinning in men is male pattern baldness,^[1] or androgenetic alopecia. Male pattern baldness is characterized by hair receding from the lateral sides of the forehead (known as a "receding hairline") and/or a thinning crown (balding to the area known as the ‘vertex’. Both become more pronounced until they eventually meet, leaving a horseshoe-shaped ring of hair around the back of the head.

The incidence of pattern baldness varies from population to population based on genetic background. Environmental factors do not seem to affect this type of baldness greatly. One large scale study in Maryborough, Victoria, Australia showed the prevalence of mid-frontal hair loss increases with age and affects 73.5 percent of men and 57 percent of women aged 80 and over. A rough rule of thumb is that the incidence of baldness in males corresponds to chronological age. For example, according to Medem Medical Library's website, male pattern baldness (MPB) affects roughly 40 million men in the United States. Approximately 25 percent of men begin balding by age 30; two-thirds begin balding by age 60.

There is a 4 in 7 chance of receiving the baldness gene^[2] Onset of hair loss sometimes begins as early as the end of puberty, and is mostly genetically determined. It was previously believed that baldness was inherited from the maternal grandfather. While there is some basis for this belief, both parents contribute to their offspring's likelihood of hair loss. Most likely, inheritance is technically "autosomal dominant with mixed penetrance"^{[citation needed]}.

The trigger for this type of baldness is DHT, a powerful sex hormone, body- and facial-hair growth promoter that can adversely affect the prostate as well as the hair located on the head.^[3] The mechanism by which DHT accomplishes this is not yet fully understood. In genetically-prone scalps, i.e. those experiencing male or female pattern baldness, DHT initiates a process of follicular miniaturization, in which the hair follicle begins to deteriorate. As a consequence, the hair’s growth phase (anagen) is shortened, and young, unpigmented vellus hair is prevented from growing and maturing into the deeply-rooted and pigmented terminal hair that makes up 90 percent of the hair on our heads.^[4] In time, hair becomes thinner and its overall volume is reduced, resembling fragile vellus hair or "peach fuzz" until, finally, the follicle falls dormant and ceases producing hair completely.

There are several other kinds of hair thinning:

Traction alopecia is most commonly found in people with ponytails or cornrows who pull on their hair with excessive force. In addition, rigorous brushing and heat styling, rough scalp massage can damage the cuticle, the hard outer casing of the hair. This causes individual strands to become weak and break off, reducing overall hair volume.
Trichotillomania is the loss of hair caused by compulsive pulling and bending of the hairs. It tends to occur more in children than in adults. In this condition the hairs are not absent from the scalp but are broken. Where they break near the scalp they cause typical, short, "exclamation mark" hairs.
Traumas such as, childbirth, major surgery, poisoning, and severe stress may cause a hair loss condition known as telogen effluvium,^[5] in which a large number of hairs enter the resting phase at the same time, causing shedding and subsequent thinning. The condition also presents as a side effect of chemotherapy – while targeting dividing cancer cells, this treatment also affects hair’s growth phase with the result that almost 90% of hairs fall out soon after chemotherapy starts.^[6]
Radiation to the scalp, as happens when radiotherapy is applied to the head for the treatment of certain cancers there, can cause baldness of the irradiated areas.
Temporary or permanent hair loss can be caused by several medications, including those for blood pressure, diabetes, heart disease and cholesterol.^[7] Any that affect the body’s hormone balance can have a pronounced effect, and these include the contraceptive pill, hormone replacement therapy, steroids and acne medications.^[8]
Worrisome hair loss often follows childbirth without causing actual baldness. In this situation, the hair is actually thicker during pregnancy due to increased circulating oestrogens. After the baby is born, the oestrogen levels fall back to normal pre-pregnancy levels and the additional hair foliage drops out. A similar situation occurs in women taking the fertility-stimulating drug clomiphene.
Studies have shown that poor nutrition, limited food intake, and deficiencies in certain nutrients can cause thinning. These include in biotin, protein or zinc and human iron metabolism, although complete baldness is not usually seen. A diet high in animal fats (often found in fast food) and Vitamin A is also thought to have an effect on hair loss.
Stress has been shown to restrict the blood supply to capillaries, inhibiting oxygen and nutrient uptake to hair follicles and inhibiting hair growth, in a similar effect to having poor circulation.
Air and water pollutants, as well as minerals in water and the phototoxic effects of sunlight, can cause thinning by aging the scalp skin and damaging hair.
Some treatments used to cure mycotic infections can cause massive hair loss.^[9]
Alopecia areata is an autoimmune disorder also known as "spot baldness" that can result in hair loss ranging from just one location (Alopecia areata monolocularis) to every hair on the entire body (Alopecia areata universalis). Although thought to be caused by hair follicles becoming dormant, it is not known for sure what triggers alopecia areata. In most cases the condition corrects itself, but it can also spread to the entire scalp (alopecia totalis) or to the entire body (alopecia universalis).
Localized or diffuse hair loss may also occur in cicatricial alopecia (lupus erythematosus, lichen plano pilaris, folliculitis decalvans, central centrifugal cicatricial alopecia, postmenopausal frontal fibrosing alopecia, etc.). Tumours and skin outgrowths also induce localized baldness (sebaceous nevus, basal cell carcinoma, squamous cell carcinoma).
Hypothyroidism (an under-active thyroid) and the side effects of its related medications can cause hair loss, typically frontal, which is particularly associated with thinning of the outer third of the eyebrows (also seen with syphilis). Hyperthyroidism (an over-active thyroid) can also cause hair loss, which is parietal rather than frontal.
Temporary loss of hair can occur in areas where sebaceous cysts are present for considerable duration; normally one to several weeks in length.
Congenital triangular alopecia – It is a triangular, or oval in some cases, shaped patch of hair loss in the temple area of the scalp that occurs mostly in young children. The affected area mainly contains vellus hair follicles or no hair follicles at all, but it does not expand. Its causes are unknown and although it is a permanent condition, it does not have any other effect on the affected individuals.^[10]
Gradual thinning of hair with age is a natural condition known as involutional alopecia. This is caused by an increasing number of hair follicles switching from the growth, or anagen phase, into a resting phase, or telogen phase, so remaining hairs become shorter and fewer in number.
An unhealthy scalp environment can play a significant role in hair thinning by contributing to miniaturization or causing damage. Air and water pollutants, environmental toxins, conventional styling products and excessive amounts of sebum have the potential to build up on the scalp. This debris can block hair follicles and cause their deterioration and consequent miniaturization of hair. It can also physically restrict hair growth or damage the hair cuticle, leading to hair that is weakened and easily broken off before its natural lifecycle has ended.
Demodex folliculorum, a microscopic mite that feeds on the sebum produced by the sebaceous glands, denies hair essential nutrients and can cause thinning. Demodex folliculorum is not present on every scalp, and is more likely to live in an excessively oily scalp environment.

Evolutionary hypotheses

There is no consensus regarding the details of the evolution of male pattern baldness. The assertion that MPB is intended to convey a social message is supported by the fact that the distribution of androgen receptors in the scalp differs between men and women, and older men or women with high androgen levels often exhibit diffuse thinning of hair as opposed to male pattern baldness.

Male pattern baldness is mostly the result of a genetic event that causes dihydrotestosterone (DHT), a male hormone, to cause the hair follicles to atrophy. The hair produced is progressively smaller, until it is practically invisible (or may disappear completely). It has been speculated that this is an evolutionary event that signifies maturity and conveys greater authority on affected men.

In a study by Muscarella and Cunningham,^[11] males and females viewed 6 male models with different levels of facial hair (beard and mustache or none) and cranial hair (full head of hair, receding and bald). Participants rated each combination on 32 adjectives related to social perceptions. Males with facial hair and those with bald or receding hair were rated as being older than those who were clean-shaven or had a full head of hair. Beards and a full head of hair were seen as being more aggressive and less socially mature, and baldness was associated with more social maturity.

Other evolutionary hypotheses include genetic linkage to beneficial traits unrelated to hair loss and genetic drift.

Non-human baldness

Baldness is not only a human trait. Some other primates, such as chimpanzees, stump-tailed macaques, and South American uakari show progressive thinning of the hair on the scalp after adolescence^{[citation needed]}. Adult stump-tailed macaques, in fact, are commonly used in laboratories for the testing of hair-regrowth treatments.^{[citation needed]}

One interesting case study is the bald Tsavo lion. The Tsavo lions prides are unique in that they frequently have only a single male lion with an average of 7 to 8 adult females, opposed to 4 females in other lion species prides. It is theorized that Tsavo males may have heightened levels of testosterone, which could explain both their reputation for aggression and dominance, indicating that baldness may at one time had an alpha correlation.^[12]

Genetics

Main article: Androgenic alopecia

Much research went into the genetic component of male pattern baldness, or androgenetic alopecia (AGA). Research indicates that susceptibility to premature male pattern baldness is largely the cause of sex-influenced inheritance (because males can pass on the trait to their sons which would be impossible if it were x-linked). Other genes that are not sex linked are also involved.

German researchers name the androgen receptor gene as the cardinal prerequisite for balding.^[13] They conclude that a certain variant of the androgen receptor is needed for AGA to develop. In the same year the results of this study were confirmed by other researchers.^[14] This gene is recessive and a female would need two X chromosomes with the defect to show typical male pattern alopecia. Seeing that androgens and their interaction with the androgen receptor are the cause of AGA it seems logical that the androgen receptor gene plays an important part in its development.

Other research in 2007 suggests another gene on the X chromosome, that lies close to the androgen receptor gene, is an important gene in male pattern baldness. They found the region Xq11-q12 on the X-chromosome to be strongly associated with AGA in males. They point at the EDA2R gene as the gene that is mostly associated with AGA. This finding has been replicated in at least three following independent studies.

Other genes involved with hair loss have been found, including a gene located at 3q26.^[15] This gene is also involved in a type of baldness associated with mental retardation. This gene is recessive .

Another gene that might be involved in hair loss is the P2RY5. This gene is linked to hair structure. Certain variants can lead to baldness at birth while another variant causes "wooly hair".^[16]

Recent research confirmed the X linked androgen receptor as the most important gene. With a gene on chromosome 20 being the second most important determinant gene (snpedia). This research suggest that heredity AGA is X linked, however, research has also shown that a person with a balding father has a significantly greater chance of experiencing hair loss. Men whose fathers had experienced hairloss were 2.5 times more likely to experience hairloss themselves, regardless of the mother's side of the family, which may suggest Y linked heredity plays a role.^[17]^[18]

Female hair loss

Although baldness is not as common in women as in men, the psychological effects of hair loss tend to be much greater. Typically the frontal hairline is preserved but the density of hair is decreased on all areas of the scalp. Previously it was believed to be caused by testosterone just as in male baldness, but most women who lose hair have normal testosterone levels.^[19]

However, female hair loss has become a growing problem which, according to the American Academy of Dermatology, affects around 30 million women in the United States. Although hair loss in females normally occurs after the age of 50 or even later when it does not follow events like pregnancy, chronic illness, crash diets, and stress among others, it is now occurring at earlier ages with reported cases in women as young as 15 or 16.^[20]

Causes of female hair loss may vary from those that affect men. In the case of androgenic alopecia female hair loss occurs as a result of the action of androgens hormones (testosterone, androsteinedione, and dihydrotestosterone (DHT)). These male hormones normally occur in small amounts in women.

However, according to Ted Daly, MD, a dermatologist from Nassau University Medical Center on Long Island, androgenic alopecia is not the main cause of hair loss in women and dermatologists now prefer to call this condition female pattern hair loss (or Ludwig Pattern Baldness after the scale developed to diagnose it) instead of using the term androgenic alopecia. He adds that the female pattern is diffuse and goes around the whole top of the head and can affect women at any time.^[21]

There are other instances in which the actions of hormones may also cause female hair loss. Some examples are: pregnancy, menopause, presence of ovarian cysts, birth control pills with a high androgen index, polycystic ovary syndrome. Also thyroid disorders, anemia, chronic illness and some medications can also cause female hair loss.^[22]

Signs and symptoms

Excessive daily hair loss

It is generally accepted that each person has between 100,000 and 150,000 hairs on their head (blondes have the most, followed by brunettes and redheads). Advice about how many strands it is normal to lose per day varies, but recent studies suggest an average of 100.^[23] In order to maintain a normal volume it must be replaced at the same rate. The first signs of hair thinning that people will often notice are more hairs than usual left in their hairbrush after brushing, or in the basin after shampooing. Styling can also reveal areas of thinning, such as a wider parting or thinning crown.

Skin conditions

A substantially blemished face, back and limbs could point to cystic acne. The most severe form of the condition, cystic acne arises from the same hormonal imbalances that cause hair loss, and is associated with DHT production.^[24] Seborrheic dermatitis, a condition in which an excessive amount of sebum is produced and builds up on the scalp (looking like an adult cradle cap) is also a symptom of hormonal imbalances, as is an excessively oily or dry scalp. Both can cause hair thinning.

Management

Main article: Management of baldness

Diagnosing and testing

Noticing thinning

Hair stylists can play an important role in diagnosing thinning. In many cases, they will be the first person to notice it, and they can often recommend a solution based on the specific needs of their client.

Testing

There are two types of identification tests for female pattern baldness: the Ludwig Scale and the Savin Scale. Both track the progress of diffused thinning, which typically begins on the crown of the head behind the hairline, and becomes gradually more pronounced. For male pattern baldness, the Norwood Scale tracks the progress of a receding hairline and/or a thinning crown, through to a horseshoe-shaped ring of hair around the head and on to total baldness.

Medical consultation

In almost all cases of thinning, and especially in cases of severe hair loss, it is recommended to seek advice from a doctor or dermatologist. Many types of thinning have an underlying genetic or health-related cause, which a qualified professional will be able to diagnose.

Psychological effects

Background

Perhaps unsurprisingly, hair thinning and baldness causes stress for sufferers, a fact which can be attributed to the psychology of appearance. Although societal interest in appearance has a long history, this particular branch of psychology came into its own during the 1960s and has gained momentum as messages associating physical attractiveness with success and happiness grow more prevalent.^[25] In 1984, psychologist Dr. Stephen L. Franzoi and Dr. Stephanie A. Shields developed the Body Esteem Scale,^[26] which aims to achieve a comprehensive overview about how participants feel about their bodies (including their hair), and is still used today.

Emotional reactions

The psychology of hair thinning is a complex issue. Hair is considered an essential part of overall identity: especially for women, for whom it often represents femininity and attractiveness. Men typically associate a full head of hair with youth and vigor. Although they may be aware of pattern baldness in their family, many are uncomfortable talking about the issue. Hair thinning is therefore a sensitive issue for both sexes. For sufferers, it can represent a loss of control and feelings of isolation. People experiencing hair thinning often find themselves in a situation where their physical appearance is at odds with their own self-image, and commonly worry that they appear older than they are or less attractive to others. Psychological problems due to baldness, if present, are typically most severe at the onset of symptoms.^[27]

Alopecia induced by cancer chemotherapy has been reported to cause changes in self-concept and body image. Body image does not return to the previous state after regrowth of hair for a majority of patients. In such cases, patients have difficulties expressing their feelings (alexithymia) and may be more prone to avoiding family conflicts. Family therapy can help families to cope with these psychological problems if they arise.^[28]

Some balding men may feel proud of their baldness, feeling a kindred relationship with famous charismatic bald men, such as Michael Jordan, Yul Brynner, Bruce Willis, Vin Diesel, Jack Nicholson, Sean Connery, Jason Statham, Patrick Stewart, Ben Kingsley, "Stone Cold" Steve Austin, Tupac Shakur, Michael Chiklis, Jason Alexander, Telly Savalas, Steve Wilkos, and Jeffrey Eugenides. Larry David specifically uses his baldness as a form of self-deprecating humor in his TV shows Seinfeld and Curb Your Enthusiasm. Baldness has, in recent years, become less of a liability due to an increasing fashionable prevalence of very short, or even completely shaven, hair among men in western countries. For instance, Patrick Stewart was called "The Sexiest Man on TV" for his charismatic role as Captain Jean-Luc Picard on Star Trek: The Next Generation.

Preventing and reversing hair loss

There is currently no way to instigate permanent re-growth of hair that has been lost through genetic or hormonal causes. However, it is widely regarded that with early detection, professional consultation and specialist products, the effects of hair thinning can be reduced or delayed. If the cause is reversible, such as an underlying medical condition, it is possible to stop hair thinning by treating the deficiency.^[29] There are also several measures sufferers can take to give hair a thicker appearance and to create an optimum scalp environment for new hair to grow and thrive.

A variety of medications have been proven to slow hair thinning, help grow new hair or enlarge existing hairs to create better coverage. Most require long-term use as, if stopped, hair loss returns.^[30] Some treatments are topical, and activated by being sprayed or rubbed into the scalp, while others are taken in pill form. One of the most popular medications, corticosteroids, are either injected into the scalp, taken in pill form or applied in an ointment, and are used especially to treat patchy hair loss.

Treatments for the various forms of alopecia have limited success. Some hair loss sufferers make use of clinically proven treatments such as finasteride, dutasteride and topically applied minoxidil solution, in an attempt to prevent further loss and regrow hair. As a general rule, it is easier to maintain remaining hair than it is to regrow; however, the treatments mentioned may prevent hair loss from Androgenetic alopecia.

In the United States, there are only two drug-based treatments that have been approved by the U.S. Food and Drug Administration (FDA) and one product that has been cleared by the FDA for the treatment of androgenetic alopecia, otherwise known as male or female pattern hair loss. The two FDA approved treatments are finasteride (marketed for hair loss as Propecia) and minoxidil.

Stress reduction (corticotrophin-releasing factor)

Stress reduction can be helpful in slowing hair loss. In 2011, US researchers from the University of California and the US Veterans Administration found that mice who had been genetically engineered to produce excessive levels of Corticotropin-releasing hormone (CRF),^[31]^[32]^[33] lost hair from their backs.^[31]^[32]^[33] The high amounts of Corticotropin-releasing hormone created a chronic stress condition in the mice.^[31]^[32]^[33] After treatment with Astressin-B, a CRF blocker, the mice had regrown the hair they had lost, four months later.^[31]^[32]^[33]

Surgical treatments

Hair transplant surgery was developed during the 1950s, although the earliest successful hair transplantation research was done in 1939 by a Japanese dermatologist, Dr. Okuda.^[34] Usually carried out under local anaesthetic, a surgeon will move healthy hair from the back and sides of the head to areas of thinning, helping to restore a natural look. The procedure can take anything between four and eight hours, and additional sessions can be carried out to make hair even thicker. Transplanted hair falls out within a few weeks, but regrows permanently within months.^[35] A decision to proceed with medication or hair restoration should always be made in consultation with a medical professional.

Immunosuppressants

Immunosuppressants applied to the scalp have been shown to temporarily reverse alopecia areata, though the side effects of some of these drugs make such therapy questionable.^[36]^[37]

Treating the scalp

As an extension of facial skin, effective cleansing and moisturizing of the scalp can help keep follicles open and create an optimum environment for healthy hair to grow and mature, preventing miniaturization and controlling thinning. Certain products on the market are specially designed to remove the styling build-up, environmental pollutants and excess sebum that block follicles and inhibit hair growth, and nourish the scalp skin and hair to reduce breakage and promote health.

Concealing hair loss

Head

One method of hiding hair loss is the "comb over", which involves restyling the remaining hair to cover the balding area. It is usually a temporary solution, useful only while the area of hair loss is small. As the hair loss increases, a comb over becomes less effective. When this reaches a stage of extreme effort with little effect—it can make the person the object of teasing or scorn.

Another method is to wear a hat or a hairpiece—a wig or toupee. The wig is a layer of artificial or natural hair made to resemble a typical hair style. In most cases the hair is artificial. Wigs vary widely in quality and cost. In the United States, the best wigs—those that look like real hair—cost up to tens of thousands of dollars. Organizations also collect individuals' donations of their own natural hair to be made into wigs for young cancer patients who have lost their hair due to chemotherapy or other cancer treatment in addition to any type of hair loss.

Lastly a number of alternative topical camouflages exist such as Nanogen (Europe) and Toppik (U.S.) and these are very popular as non-wig cosmetics which add electrostatic microfibres to your own hair.

Eyebrows

Though not as common as the loss of hair on the head, chemotherapy, hormone imbalance, forms of alopecia, and other factors can also cause loss of hair in the eyebrows. Artificial eyebrows are available to replace missing eyebrows or to cover patchy eyebrows. Micro tattooing is also available.

Embracing baldness

Society and culture

There are many myths regarding the possible causes of baldness and its relationship with one's virility, intelligence, ethnicity, job, social class, wealth etc. While skepticism is warranted due to lack of scientific validation, some of these myths may have a degree of underlying truth.

"You inherit baldness from your mother's father."
- Previously, early baldness of the androgenic type was thought to be sex linked dominant in males and to be sex linked recessive in females.^{[citation needed]}
- Research suggests that the gene for the androgen receptor, which is significant in determining probability for hair loss, is located on the X chromosome and so is always inherited from the mother's side.^[38] There is a 50% chance that a person shares the same X chromosome as his maternal grandfather. Because women have two X chromosomes, they will have two copies of the androgen receptor gene while men only have one. However, research has also shown that a person with a balding father also has a significantly greater chance of experiencing hair loss. Men whose fathers had experienced hairloss were 2.5 times more likely to experience hairloss themselves, regardless of the mother's side of the family.^[17]^[18]
"Weight Training and other types of physical activity causes baldness."
- Because it increases testosterone levels many internet forums have put forward the idea that weight training and other forms of exercise increase hair loss in pre-disposed individuals. Although scientific studies do support a correlation between exercise and testosterone, no direct study has found a link between exercise and baldness. However a few have found a relationship between sedentariness and baldness, suggesting that some exercise is beneficial. It is possible that the type of quantity of exercise may influence hair loss, more studies are needed. ^[39] ^[40]

Note that testosterone levels are not a good marker of baldness and many studies actually show a paradoxical low testosterone in balding persons although research on the implications of this is limited.

"Intellectual activity or psychological problems can cause baldness."
- This notion may be because cholesterol is involved in the process of neurogenesis and also the base material from which the body ultimately manufactures DHT. While the notion that bald men are more intelligent may lack credibility in the modern world, in the ancient world if a person was bald it was likely that he had an adequate amount of fat in his diet. Thus, his mental development was probably not stunted by malnutrition during his crucial formative years, he was more likely to be wealthy, and also have had access to a formal education. However, a sedentary lifestyle is less likely to correlate with intelligence in the modern world, and dietary fat content is not linked to economic class in modern developed countries. Another possibility is that, for some people, social standing accrued through intelligence can in mating compensate for physical attractiveness lowered by hair loss and therefore produce male offspring who are prone to both high intellect and hair loss. However, by way of better socioeconomic standing and in turn more access to hair loss treatments, an association between intelligence and actual hair loss is less likely in recent times. Of course, aside from all these scientific reasons, baldness could be linked to intellect or wisdom simply because people go bald as they age and become more experienced.
- Total testosterone exhibits a positive relation to tactual-spatial abilities and to the degree of lateralization. Total testosterone is negatively correlated with verbal fluency. Testosterone in the saliva is also significantly positively correlated to tactual-spatial test scores and, in addition, to field independence. DHT and the ratio DHT/total testosterone are positively related to verbal fluency and negatively to the degree of lateralization of tactual-spatial performance.^[41]
"Baldness can be caused by emotional stress, sexual frustration etc."
- Emotional stress has been shown to accelerate baldness in genetically susceptible individuals.^[42]
- Stress due to sleep deprivation in military recruits lowered testosterone levels, but is not noted to have affected SHBG.^[43] Thus, stress due to sleep deprivation in fit males is unlikely to elevate DHT, which causes male pattern baldness. Whether it can cause hair loss by some other mechanism is not clear.
"Bald men are more 'virile' or sexually active than others."
- Levels of free testosterone are strongly linked to libido and also DHT levels, but unless free testosterone is virtually non-existent levels have not been shown to affect virility. Men with androgenic alopecia are more likely to have a higher baseline of free androgens. However, sexual activity is multifactoral, and androgenic profile is also not the only determining factor in baldness. Additionally, because hair loss is progressive and free testosterone declines with age, a person's hairline may be more indicative of their past than present disposition.^[44]^[45]
"Frequent ejaculation causes baldness"
- There are many misconceptions about what can help prevent hair loss, one of these being that lack of sexual activity will automatically prevent hair loss. While there has been proven to be a direct correlation between increased frequency of ejaculation and increased levels of DHT, as shown in a recent study by Harvard Medical School,^[46] the study suggests that ejaculation frequency is a sign, rather than a cause, of higher DHT levels. Moreover, MBP is genetically determined and theoretically occurs even with low levels of DHT. While reducing or even abstaining from sexual activity may not completely prevent hair loss in men who are genetically prone to it, it may slow down the process of balding due to the resulting lower levels of DHT, which causes male pattern baldness.^[47]

No correlation analysis has been done on this, although marital status has been shown to be influence hair loss in cross sectional studies (NHANES1).

"Standing on one's head alleviates baldness"
- While this may be a myth, increased circulation to the scalp can help provide hair follicles with needed nourishment to grow strong healthy hair.
"Tight hats cause baldness."
- While this may be a myth, hats do cause hair breakage and, to a lesser degree, split ends. Since hats are not washed as frequently as other clothing, they can also lead to scalp uncleanliness and possible Pityrosporum ovale contamination in men with naturally oily scalps. Some scalp infections, if left untreated, can cause hair loss.

Etymology

The term alopecia ( /ˌæloʊˈpiːʃə/) is formed from the Greek alópex (αλώπηξ), meaning fox. The origin of this usage is because this animal sheds its coat twice a year.

The term bald likely derives from the English word balde, which means "white, pale", or Celtic ball, which means "white patch or blaze", such as on a horse's head.^[48]

Research

Research is looking into connections between hair loss and other health issues. While there has been speculation about a connection between early-onset androgenetic alopecia and heart disease, a review of articles from 1954 to 1999 found no conclusive connection between baldness and coronary artery disease. The dermatologists who conducted the review suggested further study was needed.^[49]

Environmental factors are under review. A 2007 study indicated that smoking may be a factor associated with age-related hair loss among Asian men. The study controlled for age and family history, and found statistically significant positive associations between moderate or severe androgenetic alopecia and smoking status.^[50]

In May 2007, researchers at the University of Pennsylvania unveiled a new scientific breakthrough that may cure baldness with stem cells. A product could be on the market within three years.^[51]^[52] The researchers discovered that the growth of new hair producing follicles could be stimulated in mice by damaging their skin.^[53]

In February 2008 researchers at the University of Bonn announced they have found the genetic basis of two distinct forms of inherited hair loss, opening a broad path to treatments for baldness. The fact that any receptor plays a specific role in hair growth was previously unknown to scientists and with this new knowledge a focus on finding more of these genes may be able to lead to therapies for very different types of hair loss.^[54]^[55]

An eight month study performed at the School of Pharmaceutical Sciences at the University of Science Malaysia showed daily supplements of a patented tocotrienol (vitamin E) complex may increase hair growth in people with male pattern baldness by 42 percent.^[56]

In May 2009, researchers in Japan identified a gene, SOX21, that appears to be responsible for hair loss in people.^[57]

In December 2010, scientists at the Berlin Technical University in Germany revealed they have grown the world's first artificial hair follicles from stem cells. Research leader Dr Roland Lauster said within five years millions of hair-loss sufferers could grow new hair from their own stem cells and have it implanted into their bald spots. He also announced that preparations for clinical trials were "already in motion".^[58]

In 2011, research showed that treatment with astressin-B caused the sudden growth of hair in mice bred for a propensity for baldness. Astressin-B ia a nonselective corticotropin-releasing hormone receptor antagonist. This may possibly be used in the future to aid in the regrowth of human hair.

In 2011 Yale researchers found signals in fat cells that cause hair to grow.^[59]^[60]

In 2011 researchers used genetic twins to determine environmental vs. genetic causes of baldness. Only 66 subjects were used but the use of twins allows control for age and genetics, two powerful confounders. They found baldness associated with genetics, age, smoking, sun exposure, dandruff, a history of cancer, hypertension, sedentariness, and paradoxically, low testosterone. The latter was cited as supporting 5-alpha-reductase inhibitors which would increase the testosterone/DHT ratio. Hypertension (specifically high Diastolic blood pressure) was also found in the NHANES1 study and several others to be associated with baldness. The researchers also found marriage status in women to be associated with hair loss. ^[61]

References

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^ [1]
^ [2]
^ Berman, Jessica (17 May 2007). "Scientists Grow New Hair in Mice". VOA News (Voice of America). http://voanews.com/english/archive/2007-05/2007-05-17-voa63.cfm. Retrieved 5 January 2009. ^{[dead link]}
^ [3]
^ [4]
^ [5]
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^ http://www.gizmag.com/hair-growth-signal-source-discovery/19733/
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^ http://journals.lww.com/plasreconsurg/Citation/2011/10001/The_Relative_Contribution_of_Endogenous_and.19.aspx

External links

v d e Human hair

List of hairstyles ‎ · List of facial hairstyles

Body type	Lanugo · Androgenic · Terminal · Vellus

Hairstyles	Afro textured hair · Afro · Beehive · Blowout · Bob cut · Bouffant · Bowl cut · Braid or Plait · Bun · Odango · Buzz cut · Caesar cut · Chonmage · Comb over · Cornrows · Crew cut · Crop · Croydon facelift · Curly hair · Curtained hair · Devilock · Dido flip · Dreadlocks · Duck's Ass · Dutch braid · Emo Hair · Fauxhawk · Feathered hair · Finger wave · Flattop · Fontange · French twist · Bangs / Fringe · Highlights · High and tight · Hime cut · Hi-top fade · Induction cut · Jarhead · Jewfro · Jheri curl · Layered hair · Liberty spikes · Long hair · Mohawk · Mop-Top · Mullet · Ombre · Oseledets · Pageboy · Part · Perm · Pigtail · Pixie cut · Pompadour · Ponytail · Quiff · "The Rachel" · Rattail · Razor cut · Ringlet · Shag · Shape-Up · Spiky hair · Straight hair · Tonsure · Updo · Waves

Facial hair	Beard · Chin curtain · Chinstrap · Goatee · Handlebar moustache · Moustache · Neckbeard · Shenandoah · Sideburns · Soul patch · Stubble · Toothbrush moustache · Van Dyke

Other areas	Head · Underarm · Chest · Abdominal · Pubic · Leg

Hair loss	Baldness · Glabrousness · Hair removal (waxing · threading · laser · IPL · chemical · electric) · Shaving (head · leg) · Razor

Conditions	Alopecia · Hypertrichosis · Trichophilia · Trichotillomania

Related	Hairstyle · Hairdresser · Barber · Long hair · Hair color · Bearded lady

Category: Hair

Disorders of skin appendages (L60–L75, 703–706)

Nail

thickness: Onychogryphosis · Onychauxis

color: Beau's lines · Yellow nail syndrome · Leukonychia · Azure Lunula

shape: Koilonychia · Nail clubbing

behavior: Onychotillomania · Onychophagia

other: Ingrown nail · Anonychia

ungrouped: Paronychia (Acute paronychia, Chronic paronychia ) · Chevron nail · Congenital onychodysplasia of the index fingers · Green nails · Half and half nails · Hangnail · Hapalonychia · Hook nail · Lichen planus of the nails · Longitudinal erythronychia · Malalignment of the nail plate · Median nail dystrophy · Mees' lines · Melanonychia · Muehrcke's lines · Nail–patella syndrome · Onychoatrophy · Onychocryptosis · Onycholysis · Onychomadesis · Onychomatricoma · Onychomycosis · Onychophosis · Onychoptosis defluvium · Onychorrhexis · Onychoschizia · Platonychia · Pincer nails · Plummer's nail · Psoriatic nails · Pterygium inversum unguis · Pterygium unguis · Purpura of the nail bed · Racquet nail · Red lunulae · Shell nail syndrome · Splinter hemorrhage · Spotted lunulae · Staining of the nail plate · Stippled nails · Subungual hematoma · Terry's nails · Twenty-nail dystrophy

Hair

Hair loss/
Baldness

noncicatricial alopecia: Alopecia/Alopecia areata (Alopecia totalis, Alopecia universalis, Ophiasis)
Androgenic alopecia (male-pattern baldness) · Hypotrichosis · Telogen effluvium · Traction alopecia · Lichen planopilaris · Trichorrhexis nodosa · Alopecia neoplastica · Anagen effluvium · Alopecia mucinosa

cicatricial alopecia: Pseudopelade of Brocq · Central centrifugal cicatricial alopecia · Pressure alopecia · Traumatic alopecia · Tumor alopecia · Hot comb alopecia · Perifolliculitis capitis abscedens et suffodiens · Graham-Little syndrome · Folliculitis decalvans

ungrouped: Triangular alopecia · Frontal fibrosing alopecia · Marie Unna hereditary hypotrichosis

Hypertrichosis

Hirsutism · Acquired generalized hypertrichosis · Generalized congenital hypertrichosis · Localized acquired hypertrichosis · Localized congenital hypertrichosis · Patterned acquired hypertrichosis · Prepubertal hypertrichosis · X-linked hypertrichosis

Acneiform eruption

Acne	Acne vulgaris · Acne conglobata · Acne miliaris necrotica · Tropical acne · Infantile acne/Neonatal acne · Excoriated acne · Acne fulminans · Acne medicamentosa (e.g., steroid acne) · Halogen acne (Iododerma, Bromoderma, Chloracne) · Oil acne · Tar acne · Acne cosmetica · Occupational acne · Acne aestivalis · Acne keloidalis nuchae · Acne mechanica · Acne with facial edema · Pomade acne · Acne necrotica · Blackhead · Lupus miliaris disseminatus faciei

Rosacea	Perioral dermatitis (Granulomatous perioral dermatitis) · Phymatous rosacea (Rhinophyma, Blepharophyma, Gnathophyma, Metophyma, Otophyma) · Papulopustular rosacea · Lupoid rosacea · Erythrotelangiectatic rosacea · Glandular rosacea · Gram-negative rosacea · Steroid rosacea · Ocular rosacea · Persistent edema of rosacea · Rosacea conglobata · variants (Periorificial dermatitis, Pyoderma faciale)

Ungrouped	Granulomatous facial dermatitis · Idiopathic facial aseptic granuloma · Periorbital dermatitis · SAPHO syndrome

Follicular cysts

Epidermoid cyst · Trichilemmal cyst · Sebaceous cyst · Steatocystoma multiplex · Milia

Inflammation

Folliculitis (Folliculitis nares perforans, Tufted folliculitis) · Pseudofolliculitis barbae
Hidradenitis (Hidradenitis suppurativa, Recurrent palmoplantar hidradenitis, Neutrophilic eccrine hidradenitis)

Ungrouped

Acrokeratosis paraneoplastica of Bazex · Acroosteolysis · Bubble hair deformity · Disseminate and recurrent infundibulofolliculitis · Erosive pustular dermatitis of the scalp · Erythromelanosis follicularis faciei et colli · Hair casts · Hair follicle nevus · Intermittent hair–follicle dystrophy · Keratosis pilaris atropicans · Kinking hair · Koenen's tumor · Lichen planopilaris · Lichen spinulosus · Loose anagen syndrome · Menkes kinky hair syndrome · Monilethrix · Parakeratosis pustulosa · Pili (Pili annulati · Pili bifurcati · Pili multigemini · Pili pseudoannulati · Pili torti) · Pityriasis amiantacea · Plica neuropathica · Poliosis · Rubinstein–Taybi syndrome · Setleis syndrome · Traumatic anserine folliculosis · Trichomegaly · Trichomycosis axillaris · Trichorrhexis (Trichorrhexis invaginata · Trichorrhexis nodosa) · Trichostasis spinulosa · Uncombable hair syndrome · Wooly hair · Wooly hair nevus

Sweat glands

Eccrine	Miliaria (Colloid milium • Miliaria crystalline • Miliaria profunda • Miliaria pustulosa • Miliaria rubra • Occlusion miliaria • Postmiliarial hypohidrosis), Granulosis rubra nasi, Ross’ syndrome, Anhidrosis, Hyperhidrosis (Generalized, Gustatory, Palmoplantar)

Apocrine	Body odor, Chromhidrosis, Fox–Fordyce disease

Sebaceous	Sebaceous hyperplasia

M: SKA

anat/phys/devp

noco/cong/tumr, sysi/epon

proc, drug(D10)

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alopecia

al·o·pe·cia

Alopecia

Alopecia

Alopecia

alopecia

alopecia

alopecic

alopecia

categories related to 'alopecia'

alopecia

Baldness

Cause

Evolutionary hypotheses

Non-human baldness

Genetics

Female hair loss

Signs and symptoms

Excessive daily hair loss

Skin conditions

Management

Diagnosing and testing

Noticing thinning

Testing

Medical consultation

Psychological effects

Background

Emotional reactions

Preventing and reversing hair loss

Stress reduction (corticotrophin-releasing factor)

Surgical treatments

Immunosuppressants

Treating the scalp

Concealing hair loss

Head

Eyebrows

Embracing baldness

Society and culture

Etymology

Research

See also

References

Further reading

External links