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Our hair is a
production of the skin in form of a filament that can be found in
almost all of the body's surface and receives different names
depending on its form and location: hair, eyelash, arm hair, etc.
The dictionary of the Royal Spanish Academy defines hair like
a furuncle that originates in our skin's pores. Only mammals have
hair. Its function is to protect the skin from outside agents. Great
part of our organism is covered in follicles, with the exception of
our hand and foot palms. Their strengths and thickness vary
according their function in the hormonal changes.
Hair is build in the follicles located in the surface of the skin. Originally,
they are are being developed in the first steps of fetal life, and
they underlie a life long regular circle. The hair circle is not
synchronized in all humans. Normally, most hair on the scalp is in
the phase of growing, while a few hair are in transition phase and
in repose of the circle. The growing phase or the follicles on the
scalp takes longer than the other phases, and this duration is
proportional o the final lengths of the hair.
The hair suffers influences from all the organism: especially
hormones, stress, tiredness...
Those influences work on the level of "the fabric of hair", the
dermic papilla, situated in the root of the hair. This papilla is
rich on cells: above all, its contains several capillary vessels,
whose number and attitude are essential.
The desire of a lot of men is to fight hair loss which already
pushed them to try out all possible products (and impossible ones),
which paved the way for all sorts of scammers. But before you want
to finally resign ("there is nothing to do anyway!"); and
get tired of the winning promises of every new "miracle" lotion that
appears on the market, you will find this reasonable method against
hair loss.
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Folículo piloso durante la fase activa de crecimiento* |
Short historic outline
Hair has an important function in all human relations.
They also form part of the events that occur over time and can be
considered the barometer of trends and eras.
Hair had different meanings during the span of History.
At times it was indicator of social status, profession,
religion or virility. From the famous case of Samson's strengths who
lost his power when Dalila cut him his hair, this particular
symbolism in connection with hair has created many curiosities, legends
and popular stories in pop culture.
The Egyptians were the first civilization that dedicated special
care to their hair. In this epoch hair was a necessity to all the
population, that took pride in their elaborate hair styles or fake
hair. All social groups wore wigs, maybe with the aim to protect
their hair from sun or to substitute their natural hair that they
shaved off for protection from parasites. But already for the
Egyptians baldness was a problem. When the tomb of the mother of
King Chita was discovered and opened you could see that already in
the year 4.000 BC. a treatment against hair loss was trying to be
developed
HAIR
IN FACTS
Number: 100.000 a 150.000.
Density: 300 a 400 por cm2.
Diameter: 40 a 100 micras (1/1000 of millimeters).
Lengths: 50 a 100 cm maximum.
Speed of growth: 1 cm per month.
Duration of growth: 3 years in average.
Normal loss: 50 a 100 per day. |
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Structure of hair,
chemical
composition
Hair is an
incredible material which, even when it is biologically dead, has
its own life. To understand it, you have to know its complex
structure. Hair sits in a depression of the skin in the scalp called
follicle, and is divided in two parts: root and stem.
· Root: In the root a big metabolic and mitotic activity is
produced. The root ends in a bulb in whose central shaft the dermic
papilla is located which nourishes the hair. When the blood
circulation is active, hair growth is rapid,
in the contrary case the opposite happens.
· Stem: Its the main part of the hair and consists of three
major parts: cuticle, cortex y medulla. The diameter of the stem is
between 70 and 100 micras, and the weight of the breaking of the
hair is approximately 40 to 60 gram.
· Cuticle: Occupies 9% of the total surface of
the hair and is like a protection coat who is resistant against
forces of physical or chemical nature who can quickly damage
the fibers of the hair when it emerges outside the skin. Its
integrity defines the shine of the hair and the ability to brush
smoothly.
· Cortex: Takes over the middle layer and occupies 70%
of the total surface of the hair, and is responsible for the
mechanic feature of the hair.
· Medulla: Represents 21% of the hair's surface. They
lie in the central part of the hair and consist of round cornea
cells, without having a nucleus and little pigments.
Hair consist of the following chemical substances:
28% protein, 2% lipids and 70% of water. The most abundant
protein is keratin that is responsible for about 85 to 90 % of the
hair's total weight. The Keratin is a protein consisting of
polypeptide chains that are very rich in cisteine. Its principle
elements are: carbon, hydrogen, oxygenic, nitrogen and sulfur. In
small quantities it contains: calcium, copper, cadmium, mercuric, zinc,
lead, iron, arsenic, silicon, magnesium, uranium, vanadium, sodium
and potassium.
Its life
circle
The growth of
human hair has a constant activity: the hair goes to distinct
phases of growth and relaxation , and each single hair has its very
own circle of growth that is different to those of the surrounding
hair one's. Every day new hairs grow on our head while others fall
out, according to a cycle that renews itself over and over again.
 Every
circle is formed by different phases: growth, regression and rest.
During a normal capillary circle, the hair grows,
rests and falls, with the goal to leave space for a new hair. It is
considered normal to lose daily between 50 and 100 hairs in average;
a higher fall could lead to disturbances in the circle.
The duration of the lengths of the circle varies according to
age and region on the body, same goes for the lengths and the
thickness of the hair.
The follicles can be found in a phase of growth or "anagen";
in a phase of transition or "catagen"; or in a phase of
repose or "telogen".
In human beings, the growth circle is not synchronized, as every day
some hair grow new and some others fall out.
Phase of growth or o anagen
The anagen is a phase of growth of the follicle .
Approximately 80% of the scalp's hair is in this phase at any
moment. Those follicles are metabolically very active and, as a
result, very sensitive to nutrition changes and chemical damage: for
example, during chemotherapy for cancer treatment, many patients
lose most of their hair.
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