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"Bald" redirects here. For other uses, see Bald (disambiguation).
| Alopecia Classification & external resources | |
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| An example of a man with Male Pattern Baldness--in this case, newspaper publisher David Ganezer. | |
| ICD-10 | L65.9 |
| ICD-9 | 704.0 |
| DiseasesDB | 14765 |
Baldness involves the state of lacking hair where it often grows, especially on the head. The most common form of baldness is a progressive hair thinning condition called androgenic alopecia or \'male pattern baldness\' that occurs in adult male humans and other species. The severity and nature of baldness can vary greatly; it ranges from male and female pattern alopecia (androgenetic alopecia, also called androgenetic alopecia or alopecia androgenetica), alopecia areata, which involves the loss of some of the hair from the head, and alopecia totalis, which involves the loss of all head hair, to the most extreme form, alopecia universalis, which involves the loss of all hair from the head and the body.
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The average human head has about 100,000 hair follicles. Each follicle can grow about 20 individual hairs in a person\'s lifetime."Growth of Human Hair" Procter & Gamble, 2003. Average hair loss is about 100 strands a day.
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, in central Victoria (Australia) showed the prevalence of mid-frontal hair loss increases with age and affects 57% of women and 73.5% of men aged 80 and over. In the United States the figure is around 23% of men and 10% of women.[citation needed]
Male pattern is characterized by hair receding from the lateral sides of the forehead, known as "receding hairline". Receding hairlines are usually seen in males above the ages of 25.
An additional bald patch may develop on top (vertex). The trigger for this type of baldness (called androgenetic alopecia) is DHT, a powerful sex hormone, body, and facial hair growth promoter that can adversely affect the hair on the head and prostate.Rebora A (2004). "Pathogenesis of androgenetic alopecia.". J Am Acad Dermatol 50 (5): 777-9. PMID 15097964. Eunuchs rarely go bald, possibly due to reduced hormone levels.[citation needed]
The mechanism by which DHT accomplishes this is not yet understood. In genetically-prone scalps, DHT initiates a process of follicular miniaturization. Through the process of follicular miniaturization, hair shaft width is progressively decreased until scalp hair resembles fragile vellus hair or "peach fuzz" or else becomes non-existent. Onset of hair loss sometimes begins as early as end of puberty, and is mostly genetically determined. Male pattern baldness is classified on the Hamilton-Norwood scale I-VII.
It was previously believed that baldness was inherited. 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" (see \'baldness folklore\' below)
There are several other kinds of baldness:
There is no consensus regarding the details of the evolution of male pattern baldness. A number of other primate species also experience hair loss following puberty, and some primate species clearly use an enlarged forehead, created both anatomically and through strategies such as frontal balding, to convey increased status and maturity. 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 women or women with high androgen levels often exhibit diffuse thinning of hair as opposed to male pattern baldness.
One theory, advanced by Muscarella and CunninghamMuscarella, F. & Cunningham, M.R. (1996). "The evolutionary significance and social perception of male pattern baldness and facial hair.". Ethology and Sociobiology 17 (2): 99-117. , suggests baldness evolved in males through sexual selection as an enhanced signal of aging and social maturity, whereby aggression and risk-taking decrease and nurturing behaviours increase. This may have conveyed a male with enhanced social status but reduced physical threat, which could enhance ability to secure reproductive partners and raise offspring to adulthood.
In a study by Muscarella and Cunnhingham , males and females viewed 6 male models with different levels of facial hair (beard and moustache or clean) 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.
Baldness is not only a human trait. Some other primates, such as chimpanzees, stump-tailed macaques, and South American nakari show progressive thinning of the hair on the scalp after adolescence. Adult stump-tailed macaques, in fact, are commonly used in laboratories for the testing of hair-regrowth treatments.
The different predecessors of Old World and New World vultures convergently evolved a bald head, preventing feathers from retaining material from the vulture\'s diet of rotting meat, as well as helping in heat regulation.Stanley Rice (September 1987). "On the Problem of Apparent Evil in the Natural World". Perspectives on Science and Christian Faith 39: 150-157.
Research is also 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. Baldness and Coronary Artery Disease Archives of Dermatology 2001;137:943-947
Environmental factors are also 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. Asian men who smoke may have increased risk for hair loss Archives of Dermatology 2007;143(11):1401-1406.
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. They found that a gene, P2RY5, causes a rare, inherited form of hair loss called Hypotrichosis simplex. It is the first receptor in humans known to play a role in hair growth. 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.[1][2]
Retired bald NASA astronaut Story Musgrave.
The psychological effects for individuals experiencing hair loss vary widely. Some people adapt to the change comfortably, while others have severe problems relating to anxiety, depression, social phobia, and in some cases, identity change.
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.Poot F (2004). "[Psychological consequences of chronic hair diseases]". Rev Med Brux 25 (4): A286-8. PMID 15516058.
Psychological problems due to baldness, if present, are typically most severe at the onset of symptoms.Passchier J, Erdman J, Hammiche F, Erdman R (2006). "Androgenetic alopecia: stress of discovery.". Psychol Rep 98 (1): 226-228. PMID 16673981.
Some balding men may feel proud of their baldness, feeling a kindred relationship with famous charismatic bald men, much of whose perceived masculinity and handsomeness derives from their most obvious distinguishing feature. Baldness has, in recent years, in any case become less of a (supposed) liability due to an increasing fashionable prevalence of very short, or even completely shaven, hair among men, at least in western countries. This is even true for women, as shown by the case of singers Sinead O\'Connor and Meshell Ndegeocello, who both have a shaven head. Other female celebrities whose baldness is involuntary include Kylie Minogue (induced by chemotherapy) and Gail Porter (believed to be of psychosomatic origin).
Many companies have built a successful business selling products that reverse baldness, by allegedly regrowing hair, transplanting hair or selling hairpieces. There is very little evidence that any of those which claim hair regrowth actually work.
In the USA, there are only two drug-based treatments that have been approved by the FDA (Food and Drug Administration) 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.
A pharmaceutical company reportedly sought to find the smallest effective quantity of finasteride and test its long-term effects on 1,553 men between ages 18 and 41 with mild to moderate thinning hair. Based on their research, 1 mg. daily was selected, and after two years of daily treatment, over 83% of the 1,553 men experiencing male hair loss had actually maintained or increased their hair count from baseline. Visual assessments concluded that over 80% had improved appearances. Medscape summary of the full article
Minoxidil was first used in tablet form as a medicine to treat high blood pressure, but it was noticed that some patients being treated with Minoxidil experienced excessive hair growth (hypertrichosis) as a side-effect. Further research showed that by applying topical Minoxidil solution directly to the scalp, it could prove to be beneficial to those experiencing hair loss.
FDA clinical trials showed that 65% of men with androgenetic alopecia maintained or increased their hair count from the use of minoxidil 5% in liquid form. 54% of these men experienced moderate to dense regrowth and 46% experienced hair loss stabilisation and mild regrowth.
In controlled clinical studies of women aged 18-45, two out of three women with moderate degrees of hereditary hair loss reported re-growth after using 2% minoxidil. Initial results occur at four months with maximum results occurring at eight months.
A low level laser is shone directly on the scalp to stimulate hair growth through "Photo-Biostimulation" of the hair follicles. One product of these low level laser therapies is the "Hairmax Lasercomb". There is no peer-reviewed evidence to support this claim. There is some debate over the FDA\'s acknowledgment of the Lasercomb, but it has been accepted by the FDA as effective in the submitted claims.LaserComb Controvery at Tressless: The Hairloss Encyclopedia The Lasercomb was cleared by the FDA as being Substantially Equivalent (SE) to predicate devices legally marketed before May 28, 1978. This clearance is not the same as approval because it only applies to the lasercomb and not to any other similar laser based hair devices. The devices that the lasercomb proved itself equivalent to were a variety of FDA approved laser based/non hair growth devices intended for hair removal and pain relief, and two non FDA approved non laser based/hair growth devices such as the Raydo & Wonder Brush and the Vacuum Cap. These last two devices were sold in the early 1900\'s and are well established as medical quackery, but they were legal to market at the time which does satisfy the FDA\'s 510k SE criteria. The 510k number for the Lasercomb is K060305.
The Leimo laser was recently approved by the TGA (Therapeutic Goods Administration) of Australia as a Class IIa Medical Device. It was approved for safety but not for efficacy of results. The company is advertising that this unit is TGA approved to grow hair, which is false. The TGA advertising board is now investigating all advertising that relates to Leimo Lasers.
Surgery is another method of reversing hair loss and baldness, although it may be considered an extreme measure. The surgical methods used include hair transplantation, whereby hair-producing follicles are taken from the back and sides of the head and injected into bald or thinning areas.
Looking forward, the prospective treatment of hair multiplication/hair cloning, which extracts self-replenishing follicle stem cells, multiplies them many times over in the lab, and microinjects them into the scalp, has been shown to work in mice, and is currently under development, expected by some scientists to be available to the public in 2009–2015. Subsequent versions of the treatment are expected by some scientists to be able to cause these follicle stem cells to simply signal the surrounding hair follicles to rejuvenate. See Baldness treatments
In October 2006, UK biotechnology firm Intercytex announced they have successfully tested a method of removing hair follicles from the back of the neck, multiplying them and then reimplanting the cells into the scalp (Hair multiplication). The initial testing resulted in 70% of male patients regrowing hair. This treatment method is expected to be available to the public by 2009 [3][4].
In January 2007, Italian stem-cell researchers say they\'ve come up with a new technique for curing baldness. Pierluigi Santi of a Genoa clinic said stem cells could be used to "multiply" hair roots. He said the clinic would be ready to perform its first hair transplants on priority patients - those who have lost their hair in fires or other accidents - within a few months. After that, he said, "we\'ll open our doors to paying customers". Santi\'s approach works by splitting roots and growing new follicles.[citation needed]
Topical application of ketoconazole, which is both an anti-fungal and a potent 5-alpha reductase inhibitor, is often used as a supplement to other approaches.
Particular unsaturated fatty acids such as gamma linolenic acid are 5 alpha reductase inhibitors if taken internally. [5]
Regular aerobic exercise can help keep androgen levels (particularly free testosterone levels) naturally lower while maintaining overall health, lowering stress and increasing SHBG. [6] [7]
Weight training without aerobic exercise may increase testosterone. [8]; [9] [10] [11] One study suggests that both heavy exercise and increased fat intake, in combination, are required for increased free testosterone in strength trainers. Increased total or free testosterone would help them build and repair muscle, but may cause susceptible individuals to lose hair. [12]
However, there is at least one study that indicates a decline in free testosterone combined with an increase in strength due to an (unspecified) strength training regime.Ara, I.; Perez-Gomez, J.; Vicente-Rodriguez, G.; Chavarren, J.; Dorado, C.; Calbet, J. A. L. (2006). "Serum free testosterone, leptin and soluble leptin receptor changes in a 6-week strength-training programme.". British Journal of Nutrition 96 (6): 1053-9.
Stress reduction can be helpful in slowing hair loss. (see Baldness Folklore)
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. [13][14]
Saw Palmetto (Serenoa repens) is an herbal DHT inhibitor often claimed to be cheaper and have fewer side effects than finasteride and dutasteride. Unlike other 5alpha-reductase inhibitors, Serenoa repens induces its effects without interfering with the cellular capacity to secrete PSA.Habib F, Ross M, Ho C, Lyons V, Chapman K (2005). "Serenoa repens inhibits the 5alpha-reductase activity of human prostate cancer cell lines without interfering with PSA expression.". Int J Cancer 114 (2): 190-4. PMID 15543614. Saw palmetto extract has been demonstrated to inhibit both isoforms of 5-alpha-reductase unlike finasteride which only inhibits the (predominant) type 2 isoenzyme of 5-alpha-reductase.Prager N, Bickett K, French N, Marcovici G (2002). "A randomized, double-blind, placebo-controlled trial to determine the effectiveness of botanically derived inhibitors of 5-alpha-reductase in the treatment of androgenetic alopecia.". J Altern Complement Med 8 (2): 143-52. PMID 12006122. Marks L, Hess D, Dorey F, Luz Macairan M, Cruz Santos P, Tyler V (2001). "Tissue effects of saw palmetto and finasteride: use of biopsy cores for in situ quantification of prostatic androgens.". Urology 57 (5): 999-1005. PMID 11337315. Iehlé C, Délos S, Guirou O, Tate R, Raynaud J, Martin P (1995). "Human prostatic steroid 5 alpha-reductase isoforms — a comparative study of selective inhibitors.". J Steroid Biochem Mol Biol 54 (5-6): 273-9. PMID 7577710.
Polygonum Multiflorum is a traditional Chinese cure for hair loss. P. multiflorum contains stilbene glycosides similar to resveratrol. [15]
Beta sitosterol, which is a constituent in many seed oils, can help to treat BHP by lowering cholesterol. If used for this purpose, an extract is best. Consuming large amounts of oil to get at small quantities of beta sitosterol is likely to exacerbate male pattern baldness.
While drastic, broad spectrum anti-androgens such as flutamide are sometimes used topically. Flutamide is potent enough to have a feminizing effect in men, including growth of the breasts.
Through 2006, a drug development company spent $1,000,000 on a hair growth program focused on the potential development of a topical hedgehog agonist for hair growth disorders such as male pattern baldness and female hair loss. The hair loss research program was shut down in May 2007 because the process did not meet the proper safety standards."Curis and Procter & Gamble Enter into R&D Agreement for Hair Growth Program". Retrieved on 2006-08-24.
In May 2007, US company Follica Inc, announced they have licensed technology from the University of Pennsylvania which can regenerate hair follicles by reawakening genes which were once active only in the embryo stage of human development.[16] [17] [18] [19] [20][21]
A spray made with coffee beans is on sale in certain Pharmacies. It is claimed to prevent age-related hair loss in women. [22]
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.
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.
Instead of concealing hair loss, one may embrace it. A shaved head will grow stubble in the same manner and at the same rate as a shaved face. The general public has become accepting of the shaved head as well, but female baldness is less socially accepted.
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.
The term alopecia (pronounced /ˌæloˈpiʃə/) is formed from the Greek alópix (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.Harper, Douglas. Entry for "bald". Online Etymology Dictionary. Retrieved on 2006-12-07.
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