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The Causes of Hair
Loss
The life of a scalp hair can range from one to six years.
As a result, everyone loses some hair each day.
When a hair is released from a hair follicle, a new hair
should be regrowing from that same follicle to replace
the hair which was lost. The new hair should be as thick
and strong as the original hair it is replacing with a
growth rate of approximately ½" to ¾" every
month. The
onset of alopecia (baldness) is very gradual. As the hair
follicles begin to weaken, the loss-replacement process
continues. However, the new replacement hairs are much
finer in diameter and lighter in color than the normal
hair previously lost. These hairs, in turn, are replaced
by even finer and lighter hairs until all that remains
are the almost invisible vellous hairs which represent the final
stage before baldness.
There are several causes
of hair loss which account for virtually all baldness.
Local and external problems are the easiest to control
before the onset of baldness. These causes vary including
hygienic, traumatic, infectious or medicinal. Among
hygienic causes are dandruff, scaling, severe itching and
scalp tenderness. In these cases time becomes very
important because the conditions must be recognized and
treated in time before the hair follicles are permanently
disabled. Genetic factors vary because an individual does
not inherit baldness as such, but rather a predisposition
to a weak follicular structure. This predisposition may
come from either the maternal or paternal side of the
family. General or acute diseases may influence the scalp
by changing its structure and interfering with normal
function. Certain internal medications may change the
normal function of the follicular structure which, as a
result, may lead to excessive hair loss.
How Your Hair
Grows
The growth of the hair depends mainly on the circulatory
system as fluids pass through the dermal papilla for two
purposes: (1) to supply the hair structure with
nourishment; and (2) to remove cellular wastes and other
unwanted products. A strong circulatory system is vital
since the temporal and posterior branches of the carotid
artery bring nutrients and amino acids to the hair
follicles. A build-up of cellular waste seems to
adversely impact the work of the dermal papilla. Other
contributing factors for normal hair growth are the proper care
of your hair and scalp as well as a balanced and
nutritional diet.
Hair growth is achieved
through cell division (mitosis) of the matrix cells of
the hair bulb in the anagen growing cycle of follicular
development. Cell mass increases and forces the hair
cells to move into the upper bulb. They harden or cornify
to join other similar cells. The mitotic activity of the
cells and the synthesis of protein within the matrix goes
on as long as the hair is growing. However, growth stops
every one to six years and brings the onset of the
catagen transition cycle. The bulb will begin to
degenerate and all mitotic activity stops. Cells then go
into the telogen resting cycle for about three months.
Fortunately, the dormant follicle, unless problems are
present, will then burst into
anagen growing activity once again and the overall
production of hair resumes.

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