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| {{DiseaseDisorder infobox |
| | #REDIRECT [[Alopecia]] |
| Name = Alopecia |
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| }}
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| {{SI}}
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| {{CMG}}
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| __NOTOC__
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| {{Editor Help}}
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| ==Overview==
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| '''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. Treatments for the various forms alopecia have limited success, but typical male pattern baldness is now a very preventable, and reversible (to a certain extent) condition. Some hair loss sufferers make use of "clinically proven treatments" such as [[finasteride]] and topically applied [[minoxidil]] (in 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 will help some of the users suffering from Androgenetic alopecia, and there are new technologies in cosmetic transplant surgery and hair replacement systems that can be completely undetectable.
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| ==Background, cause and incidence==
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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.<ref name="headfollicles">[http://www.pg.com/science/haircare/hair_twh_23.htm "Growth of Human Hair"] ''Procter & Gamble'', 2003.</ref> Average hair loss is about 100 strands a day.
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| 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.
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| 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.
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| An additional bald patch may develop on top ([[vertex (anatomy)|vertex]]). The trigger for this type of baldness (called ''androgenetic alopecia'') is [[Dihydrotestosterone|DHT]], a powerful sex hormone, body, and facial hair growth promoter that can adversely affect the hair on the head and prostate.<ref>{{cite journal | author = Rebora A | title = Pathogenesis of androgenetic alopecia. | journal = J Am Acad Dermatol | volume = 50 | issue = 5 | pages = 777-9 | year = 2004 | id = PMID 15097964}}</ref>
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| The mechanism by which [[Dihydrotestosterone|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 [[genetics|genetically]] determined. Male pattern baldness is classified on the [[Hamilton-Norwood scale]] I-VIII.
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| 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|baldness folklore]]' below)
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| There are several other kinds of baldness:
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| * [[Traction alopecia]] is most commonly found in people with ponytails or cornrows who pull on their hair with excessive force.
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| * 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.
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| * Traumas such as [[chemotherapy]], childbirth, major surgery, poisoning, and severe stress may cause a hair loss condition known as [[telogen effluvium]].<ref>{{cite journal | author = Nnoruka E, Nnoruka N | title = Hair loss: is there a relationship with hair care practices in Nigeria? | journal = Int J Dermatol | volume = 44 Suppl 1 | issue = | pages = 13-7 | year = 2005 | month = Oct | id = PMID 16187950}}</ref>
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| * 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.
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| * Iron deficiency is a common cause of thinning of the hair, though frank baldness is not usually seen.
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| * 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.
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| * Some [[fungus|mycotic]] infections can cause massive hair loss.<!--
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| --><ref>{{cite journal | author = Pappas P, Kauffman C, Perfect J, Johnson P, McKinsey D, Bamberger D, Hamill R, Sharkey P, Chapman S, Sobel J | title = Alopecia associated with fluconazole therapy. | journal = Ann Intern Med | volume = 123 | issue = 5 | pages = 354-7 | year = 1995 | id = PMID 7625624}}</ref>
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| * [[Alopecia areata]] is an [[autoimmune diseases|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'').
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| * 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).
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| * [[Hypothyroidism]] can cause hair loss, typically frontal, and is particularly associated with thinning of the outer third of the eyebrows (syphilis also can cause loss of the outer third of the eyebrows)
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| * Hyperthyroidism can also cause hair loss, which is parietal rather than frontal.
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| * Temporary loss of hair can occur in areas where [[sebaceous cyst]]s are present for considerable duration; normally one to several weeks in length.
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| == Etymology ==
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| The term ''alopecia'' (al-oh-PEE-she-uh) is formed from the Greek ''αλώπηξ'' (''alopex''), meaning fox. The origin of this usage is because this animal sheds its coat twice a year.
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| 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.<ref>{{cite web |url=http://www.etymonline.com/index.php?term=bald |title=Entry for "bald" |accessdate=2006-12-07 |last=Harper |first= Douglas|work= Online Etymology Dictionary}}</ref>
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| == Evolutionary theories of male pattern baldness ==
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| [[Image:Male silverback Gorilla.JPG|left|thumbnail|200px|]]
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| There is no consensus regarding the details of the evolution of male pattern baldness. Most theories regard it as resulting from [[sexual selection]]. A number of other primate species also experience hair loss following [[puberty]], and some primate species clearly use an enlarged [[forehead]], created both [[anatomy|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.
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| One theory, advanced by Muscarella and Cunningham, suggests baldness evolved in [[male]]s through sexual selection as an enhanced signal of aging and social maturity, whereby [[aggression]] and risk-taking decrease and [[parenting|nurturing behaviours]] increase.([[Baldness#Reference|1]]) 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.
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| 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 [[perception]]s. 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.
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| == Latest research ==
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| The LIPH gene makes LIPH, a protein that isn't thoroughly understood but seems to play a role in normal hair formation and growth"
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| http://www.hon.ch/News/HSN/536000.html
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| http://www.webmd.com/news/20061109/inherited-hair-loss-may-be-upped-by-gene-glitch
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| http://www.forbes.com/forbeslife/health/feeds/hscout/2006/11/09/hscout536000.html
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| "The so-called hairless gene works by repressing the production of a protein called wise, which can hinder the process of hair growth if it is left to accumulate."
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| http://news.bbc.co.uk/1/hi/health/4283302.stm
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| '''DSG4 gene'''
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| http://www.hairlosstalk.com/newsletter/article209.htm
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| http://www.hairlosstalk.com/download/CELL1132249.pdf
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| '''WNT GENE'''
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| http://news.bbc.co.uk/2/hi/health/6661849.stm
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| == Approaches to baldness ==
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| === Psychological effects ===
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| 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.
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| [[Image:StoryMusgrave.jpg|thumbnail|left|195px|Retired bald NASA astronaut Story Musgrave.]]
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| 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.<ref>{{cite journal | author=Poot F | title=[Psychological consequences of chronic hair diseases] | journal=Rev Med Brux | volume=25 | issue=4 | pages=A286-8 | year=2004 | id=PMID 15516058}}</ref>
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| Psychological problems due to baldness, if present, are typically most severe at the onset of symptoms.<ref>{{cite journal | author=Passchier J, Erdman J, Hammiche F, Erdman R | title=Androgenetic alopecia: stress of discovery. | journal=Psychol Rep | volume=98 | issue=1 | pages=226-228 | year=2006 | id=PMID 16673981}}</ref>
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| 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.
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| === Preventing and reversing hair loss ===
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| {{main|Baldness treatments}}
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| In the USA, there are only 2 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]].
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| ====Finasteride ====
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| 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 2 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.
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| ====Minoxidil====
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| 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.
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| [[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.
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| In controlled clinical studies of women aged 18-45, 2 out of 3 women with moderate degrees of hereditary hair loss reported re-growth after using 2% minoxidil. Initial results occur at 4 months with maximum results occurring at 8 months.
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| ====Low-level laser therapy====
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| 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.<ref>[http://tressless.com/wiki/Lasercomb#Controversy LaserComb Controvery at Tressless: The Hairloss Encyclopedia]</ref> 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 2 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 criterea. The 510k number for the Lasercomb is K060305.
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| The Leimo laser was recently approved by the TGA (Therapeutic Goods Administration) of Australia as a Class IIa Medical Device that regrows hair. Its ARTG number is 139 456.
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| ====Surgery====
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| [[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.
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| ====Hair multiplication====
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| 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#Hair multiplication (upcoming treatment)|Baldness treatments]]
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| 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 ([[Baldness treatments#Hair multiplication (upcoming treatment)|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 [http://news.bbc.co.uk/2/hi/health/5413382.stm][http://uk.news.yahoo.com/06102006/325/baldness-treating-robot-gets-funding.html].
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| 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.
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| ====Ketoconazole====
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| 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.1
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| ====Unsaturated fatty acids====
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| Particular unsaturated fatty acids such as gamma linolenic acid are 5 alpha reductase inhibitors if taken internally. [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1637346&dopt=Abstract]
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| ====Placebos====
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| Interestingly, [[placebo]] treatments in studies often have reasonable success rates, though not as high as the products being tested, and even similar side-effects as the products. For example, in Finasteride (Propecia) studies, the percent of patients with any drug-related sexual adverse experience was 3.8% compared with 2.0% in the placebo group.<ref>{{cite journal | author = Leyden J, Dunlap F, Miller B, Winters P, Lebwohl M, Hecker D, Kraus S, Baldwin H, Shalita A, Draelos Z, Markou M, Thiboutot D, Rapaport M, Kang S, Kelly T, Pariser D, Webster G, Hordinsky M, Rietschel R, Katz H, Terranella L, Best S, Round E, Waldstreicher J | title = Finasteride in the treatment of men with frontal male pattern hair loss. | journal = J Am Acad Dermatol | volume = 40 | issue = 6 Pt 1 | pages = 930-7 | year = 1999 | id = PMID 10365924 | url=http://www.hairlosstalk.com/download/finfront.pdf | format=pdf}}</ref>
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| ====Exercise====
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| Regular [[aerobic exercise]] can help keep androgen levels (particularly free testosterone levels) naturally lower while maintaining overall health, lowering stress and increasing [[SHBG]].
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| [http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=ShowDetailView&TermToSearch=17549594&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum]
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| [http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=ShowDetailView&TermToSearch=17078431&ordinalpos=29&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum]
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| Weight training without aerobic exercise may increase testosterone. [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=17003009&query_hl=25&itool=pubmed_docsum];
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| [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=12905088&query_hl=8&itool=pubmed_DocSum]
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| [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=15160600&query_hl=8&itool=pubmed_DocSum]
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| [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=17194250&query_hl=8&itool=pubmed_docsum]
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| 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.
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| [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=15532008&query_hl=8&itool=pubmed_DocSum]
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| 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.<ref>{{cite journal | author = Ara, I.; Perez-Gomez, J.; Vicente-Rodriguez, G.; Chavarren, J.; Dorado, C.; Calbet, J. A. L. | title = Serum free testosterone, leptin and soluble leptin receptor changes in a 6-week strength-training programme. | journal = British Journal of Nutrition | volume = 96 | issue = 6 | pages = 1053-9 | year = 2006 | url=http://www.ingentaconnect.com/content/cabi/bjn/2006/00000096/00000006/art00009}}</ref>
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| ====Stress reduction====
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| [[Stress reduction]] can be helpful in slowing hair loss. (see [[Baldness#Baldness folklore|Baldness Folklore]])
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| ====Immunosuppressants====
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| [[Immunosuppressant]]s 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. [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=17010743&query_hl=2&itool=pubmed_docsum][http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=11525945&query_hl=8&itool=pubmed_docsum]
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| ====Saw palmetto====
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| [[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.<!--
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| --><ref>{{cite journal | author = Habib F, Ross M, Ho C, Lyons V, Chapman K | title = Serenoa repens (Permixon) inhibits the 5alpha-reductase activity of human prostate cancer cell lines without interfering with PSA expression. | journal = Int J Cancer | volume = 114 | issue = 2 | pages = 190-4 | year = 2005 | id = PMID 15543614}}</ref>
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| 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.<!--
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| --><ref>{{cite journal | author = Prager N, Bickett K, French N, Marcovici G | title = 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. | journal = J Altern Complement Med | volume = 8 | issue = 2 | pages = 143-52 | year = 2002 | id = PMID 12006122}}</ref><!--
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| --><ref>{{cite journal | author = Marks L, Hess D, Dorey F, Luz Macairan M, Cruz Santos P, Tyler V | title = Tissue effects of saw palmetto and finasteride: use of biopsy cores for in situ quantification of prostatic androgens. | journal = Urology | volume = 57 | issue = 5 | pages = 999-1005 | year = 2001 | id = PMID 11337315}}</ref><!--
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| --><ref>{{cite journal | author = Iehlé C, Délos S, Guirou O, Tate R, Raynaud J, Martin P | title = Human prostatic steroid 5 alpha-reductase isoforms — a comparative study of selective inhibitors. | journal = J Steroid Biochem Mol Biol | volume = 54 | issue = 5-6 | pages = 273-9 | year = 1995 | id = PMID 7577710}}</ref>
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| ====Polygonum multiflorum====
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| [[Polygonum Multiflorum]] is a traditional Chinese cure for hair loss. P. multiflorum contains stilbene glycosides similar to [[resveratrol]]. [http://www.blackwell-synergy.com/doi/abs/10.1111/j.1745-4522.2006.00039.x]
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| ====Beta sitosterol====
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| 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.
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| ====Anti-androgens====
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| 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.
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| ====Hedgehog agonists====
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| 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 hairloss research program was shut down in May 2007 because the process did not meet the proper safety standards.<!--
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| --><ref>{{cite news | authro=Procter & Gamble | title=Curis and Procter & Gamble Enter into R&D Agreement for Hair Growth Program | url=http://www.pgpharma.com/news_20050919.shtml | year=2005 | month=September 19 | accessdate=2006-08-24}}</ref> <!-- Original link is dead: http://biz.yahoo.com/bw/060509/20060509005684.html?.v=1 -->
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| ====WNT gene related====
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| 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.[http://news.independent.co.uk/uk/health_medical/article2553928.ece] [http://www.guardian.co.uk/science/story/0,,2081129,00.html?gusrc=rss&feed=networkfront] [http://www.timesonline.co.uk/tol/life_and_style/health/article1800306.ece] [http://www.channel4.com/news/articles/society/health/baldness+cure+may+be+on+horizon/514157] [http://www.prnewswire.com/cgi-bin/stories.pl?ACCT=104&STORY=/www/story/05-16-2007/0004590099&EDATE=][http://www.msnbc.msn.com/id/18703259/]
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| == Concealing hair loss ==
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| === Head ===
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| 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.
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| 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 such as [http://www.wigsforkids.org/ Wigs for Kids] and [http://www.locksoflove.org/ Locks of Love] 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.
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| === Eyebrows ===
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| 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.
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| == Embracing baldness ==
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| Of course, 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. Many celebrities and athletes shave their heads. The general public has become accepting of the shaved head also.
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| Female baldness is less socially accepted.
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| == Baldness folklore ==
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| There are many myths regarding the possible causes of baldness and its relationship with one's [[masculinity|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.
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| * "You inherit baldness from your mother's father."
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| *: Previously, early baldness of the androgenic type was thought to be [[Sex linkage|sex linked dominant]] in males and to be [[Sex linkage|sex linked recessive]] in females.
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| *: 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.<!--
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| --><ref>{{cite journal | author = Hillmer A, Hanneken S, Ritzmann S, Becker T, Freudenberg J, Brockschmidt F, Flaquer A, Freudenberg-Hua Y, Jamra R, Metzen C, Heyn U, Schweiger N, Betz R, Blaumeiser B, Hampe J, Schreiber S, Schulze T, Hennies H, Schumacher J, Propping P, Ruzicka T, Cichon S, Wienker T, Kruse R, Nothen M | title = Genetic variation in the human androgen receptor gene is the major determinant of common early-onset androgenetic alopecia. | journal = Am J Hum Genet | volume = 77 | issue = 1 | pages = 140-8 | year = 2005 | id = PMID 15902657}}</ref><!--
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| -->There is a 50% chance that a person shares the same X chromosome as their 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.<!--
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| --><ref>{{cite journal | author = Chumlea W, Rhodes T, Girman C, Johnson-Levonas A, Lilly F, Wu R, Guo S | title = Family history and risk of hair loss. | journal = Dermatology | volume = 209 | issue = 1 | pages = 33-9 | year = 2004 | id = PMID 15237265}}</ref><!--
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| --><ref>[http://www.kromosoft.com/resources/KB/Abstracts/GeneticsOfPatternBaldness.php Genetics of Pattern Baldness]</ref>
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| Another model for the inheritance of baldness is "Autosomal dominant with mixed pentrance". That is, you can get it from either parent and it presents variably.
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| * "Intellectual activity or psychological problems can cause baldness."
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| *: This notion may be due to the fact that 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. Of course, aside from all these scientific reasons, baldness could be linked to intellect or wisdom simply due to the fact that people go bald as they age and become more experienced.
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| *: This is sometimes used as a [[stereotype]] in films, where the more intellectual or rather frustrated characters are most usually portrayed as bald and generally unattractive, as opposed to the main characters which are usually portrayed as attractive, fit, mentally stable and generally with no apparent hair problems.
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| *: This same myth normally extends to considering people having intellectual jobs more prone to baldness problems compared to manual laborers, sometimes further extending the myth to male college or university students when compared to workers of the same age. The myth is suspect because counterexamples can be found in any case.
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| *: There is evidence, confirmed by cross cultural studies, for an association between androgen levels and intellectual ability. These findings are controversial due to their implications regarding psychology and gender.
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| *: 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.<!--
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| --><ref>{{cite journal | author = Christiansen K | title = Sex hormone-related variations of cognitive performance in !Kung San hunter-gatherers of Namibia. | journal = Neuropsychobiology | volume = 27 | issue = 2 | pages = 97-107 | year = 1993 | id = PMID 8515835}}</ref>
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| *"One's ethnicity can increase the chances of going bald."
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| *:This idea has been seen as somewhat descriminative and sensitive in nature, however studies have shown that men of Greek or Macedonian heritage have the highest percentage of bald or balding men. (age group 16-28, typical, non married, non-drug using, males) Studies done between 6 countries in Western Europe, incl. Britain, France, Italy, Germany, Spain and Ireland and 4 countries in Eastern Europe including Greece, Macedonia, Bulgaria and Romania show that Greek men of the same age group and study period had the highest percentage of full crown baldness or Alopeciae totalis (front, top and back) Another typical study during the same period showed that Greek men, 1700 out of 2457 total studied males also suffered the highest amount of random alopecia areata among men (aged 16-28, typical, non-drug using males)
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| * "Baldness can be caused by emotional stress, sexual frustration etc."
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| *: Emotional [[stress (medicine)|stress]] has been shown to accelerate baldness in genetically susceptible individuals.<!--
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| --><ref>{{cite journal | author = Schmidt J | title = Hormonal basis of male and female androgenic alopecia: clinical relevance. | journal = Skin Pharmacol | volume = 7 | issue = 1-2 | pages = 61-6 | year = 1994 | id = PMID 8003325}}</ref>
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| *: Stress due to sleep deprivation in military recruits lowered testosterone levels, but is not noted to have effected SHBG.<!--
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| --><ref>{{cite journal | author = Remes K, Kuoppasalmi K, Adlercreutz H | title = Effect of physical exercise and sleep deprivation on plasma androgen levels: modifying effect of physical fitness. | journal = Int J Sports Med | volume = 6 | issue = 3 | pages = 131-5 | year = 1985 | id = PMID 4040893}}</ref>
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| *: 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.
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| * "Bald men are more 'virile' or sexually active than others."
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| *: 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.<ref>{{cite journal | author = Toone B, Wheeler M, Nanjee M, Fenwick P, Grant R | title = Sex hormones, sexual activity and plasma anticonvulsant levels in male epileptics. | journal = J Neurol Neurosurg Psychiatry | volume = 46 | issue = 9 | pages = 824-6 | year = 1983 | id = PMID 6413659}}</ref><!--
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| --><ref>{{cite journal | author = Davidson J, Kwan M, Greenleaf W | title = Hormonal replacement and sexuality in men. | journal = Clin Endocrinol Metab | volume = 11 | issue = 3 | pages = 599-623 | year = 1982 | id = PMID 6814798}}</ref>
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| * "Shaving hair makes it grow back stronger"
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| *: Proposed as a popular remedy against baldness, it is very probably just an illusion similar to the one perceived after [[shaving]] one's beard or mustache. Shaving one's head doesn't increase the number of healthy hair present on the scalp, and, after the remaining hair has grown a few millimeters, no enhancement in thickness or overall quality can be observed.
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| * "Frequent ejaculation causes baldness"
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| *: There are many misconceptions about what can help prevent hairloss, one of these being that frequent [[ejaculation]] may have an influence on MPB. Depending on frequency, it can raise or lower plasma testosterone. [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=11760788&query_hl=2&itool=pubmed_docsum] The claim that frequent ejaculations can cause baldness is often viewed with skepticism.
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| * "Standing on one's head alleviates baldness"
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| *: The "blood-flow" theory, which led men to stand on their heads in the 1980s, can be found in the advertising for many of the fake hairloss treatments for sale on the internet. While Minoxidil is a vasodilator and is speculated to work, in part, by increasing blood flow to hair follicles, there is no evidence that standing on one's head can alleviate baldness.
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| * "Tight hats cause baldness."
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| *: While this may be a myth, hats do cause hair breakage and, to a lesser degree, [[Trichoptilosis|split ends]]. Since hats are not washed as frequently as other clothing, they can also lead to scalp uncleanliness and possible [[Malassezia|Pityrosporum ovale]] contamination in men with naturally oily scalps.
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| == References ==
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| <div class="references-2column">
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| <references/>
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| </div>
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| == See also ==
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| {{Wiktionary}}
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| * [[Alopecia areata]]
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| * [[Alopecia universalis]]
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| * [[Trichotillomania]]
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| * [[Baldness treatments]]
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| ==Footnotes==<!-- This section is linked from [[Baldness]] -->
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| * Rossi S (Ed.) (2004). ''[[Australian Medicines Handbook]] 2004''. Adelaide: Australian Medicines Handbook. ISBN 0-9578521-4-2
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| * {{note label|1728|3|^}}{{1728}}
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| * {{cite journal | author = Stárka L, Cermáková I, Dusková M, Hill M, Dolezal M, Polácek V | title = Hormonal profile of men with premature balding. | journal = Exp Clin Endocrinol Diabetes | volume = 112 | issue = 1 | pages = 24-8 | year = 2004 | id = PMID 14758568}}
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| * Nourkrin Man research on DHT. ''[http://nourkrinman.googlepages.com/home] 2006''.
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| [[Category:Dermatology]]
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| [[Category:Hair loss]]
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