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Hair Loss in Men
By the age of forty, some degree of hair loss is evident in nearly 50% of all men. Although it is socially acceptable, it is not desirable. Historically, coping strategies have included Julius Caesar's crown of leaves and comb over. Dating as far back as history will take us, baldness has been a part of the aging process that many men fear the most. Before Rogaine, hair transplants and hair additions, men coped in various ways from magic ointments to the styling of their hair. Julius Caesar grew his hair long in the back and combed if all forward. Napoleon did the same thing. Somehow we often disregard history and the fact that this has been an age old condition. We can't imagine or accept the fact that there is not a cure. Understanding the cause of male pattern hair loss may better indicate exactly why it presently has no cure.
Androgenic Alopecia --It is estimated that 35 million men in the United States are affected by androgenic alopecia. The term "androgenic" can be broken down into two parts:
"Andro" refers to the androgens (testosterone, dihydrotestosterone) necessary to produce male-pattern hair loss.
- "Genetic" refers to the inherited gene necessary for Male pattern hair loss to occur.
Classifications of Male Pattern Hair Loss In men who develop alopecia the hair loss may begin any time after puberty when blood levels of androgens rise. The first change is usually recession in the temporal areas, which is seen in 96 percent of mature Caucasian males, including those men not destined to progress to further hair loss. Hamilton and later Norwood have classified the patterns.
Hamilton first noted that androgens (testosterone, dihydrotestosterone) are necessary for the development of (MPHL) Male Pattern Hair Loss.
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The amount of androgens present does not need to be greater than normal for MPHL to occur.
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If androgens are present in normal amounts and the gene for hair loss is present, male pattern hair loss will occur.
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Axillary (under arm) and pubic hair are dependent on testosterone for growth.
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Beard growth and male pattern hair loss are dependent on dihydrotestosterone (DHT).
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Testosterone is converted to DHT by the enzyme, 5¤ -reductase. Finasteride (Propecia®) acts by blocking this enzyme and decreasing the amount of DHT.
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Receptors exist on cells that bind androgens. These receptors have the greatest affinity for DHT followed by testosterone, estrogen, and progesterone.
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After binding to the receptor, DHT goes into the cell and interacts with the nucleus of the cell altering the production of protein by the DNA in the nucleus of the cell.
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Ultimately growth of the hair follicle ceases.
How the hair growth cycle is affected
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 The percentage of hairs in the growth phase (anagen) and the duration of the growth phase diminish resulting in shorter hairs.
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More hairs are in the resting state (telogen) and these hairs are much more subject to loss with the daily trauma of combing and washing.
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The hair shafts in MPHL become progressively miniaturized (see illustration of "Miniaturization") smaller in diameter and length.
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In men with MPHL all the hairs in an affected area may eventually (but not necessarily) become involved in the process and may with time cover the region with fine (vellus) hair. Pigment (color) production is also terminated with miniaturization so the fine hair becomes lighter in color. The lighter color, miniaturized hairs cause the area to first appear thin.
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Allopecia is an inherited condition and the gene can be inherited from either the mother or father's side.
Other Causes of Hair Loss
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Alopecia Areata -- Generally thought to be an autoimmune disorder. Cause "patchy" hair loss, often in small circular areas in different areas of the scalp.
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Alopecia Totalis -- Total hair loss of the scalp, (an advanced form of alopecia areata).
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Alopecia Universalis -- hair loss of the entire body, (also an advanced form of alopecia areata).
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Traction Alopecia -- Hair loss caused by physical stress and tension on the hair such as prolonged use of hair weaving, corn rows etc. Done too tightly on weak hair these can cause permanent hair lo
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Telogen Effluvium -- usually temporary hair loss. Causes: Physical stress -- emotional stress -- thyroid abnormalities- medications and hormonal causes normally associated with females
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Anagen Effluvium -- Generally due to internally administered medications, such as chemotherapy agents, that poison the growing hair follicle. All of these represent only a few of the different types of hair loss. Androgenetic alopecia represents close to 95% of all hair loss however.
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