RESISTING A HOSTILE WORLD

Hair is constantly under attack - from water, sun, brushes, combs and various kinds of rubbing. All capable of producing damage. Fortunately, the amazing design of its outer envelope, the cuticle, serves to offer it excellent protection. But however resilient this may be, it does become damaged.


  Marked by passing time

















If the hair's resilience does result from the structure of its cortex , its permeability and electrical properties, its shine, softness and ease of styling, are all to a great degree dependent on the state of its cuticle. And since the hair grows from its roots at an average of one centimetre per month, the tip of a 30 cm hair will therefore be 30 months old. Having undergone 2½ years of attack during which the cuticle will have been subject to considerable change. We then speak about hair which has become "sensitised".

By observing a hair throughout its length, from what is commonly misnamed the "root" until its tip, we can to some degree see what effect time has had. Close to this "root", the newly formed scales are perfectly smooth and regular, impeccably joined like newly laid roofing tiles. The further we travel from the scalp, the more eroded they appear. They first of all become scratched and their edges start to splinter.

They then begin to loosen and move apart. Some scales disappear and, at the tip of the hair, they can even be partially or completely absent - leaving the body of the hair completely exposed.

It is true, that old tiled roofs can have a lot of charm. But the same does not apply to hair because wear of its cuticle has a direct and logical influence on a great many of its qualities.

In particular, the hair's sheen is largely caused by the play of light on its smooth and regular surface, even more accentuated by its more or less cylindrical form. Wear of the scales undermines the continuity of this surface and form - affecting the evenness of the light's reflection and making the hair appear dull.

Furthermore, since touch is such a highly developed sense, almost without realising, we can feel the state of these fine scales. If they are in good condition, the hair seems soft to the touch. Whereas damaged scales make it rough.

The disjointed scales in sensitised hair produce yet another phenomenon: by becoming caught up with the scales on neighbouring hairs, they tend to tangle, producing knots which in turn become tightened during combing. This loosening of the scales is however used to advantage during back-combing. When the hair is combed from its tips towards the roots, these scales are prised loose and tangle together, so that the back-combed styling keeps its form.

Finally, at the extreme end of the hair, the frequent disappearance of the cuticle bears the cortex itself to the outside world. Derived of any protection, it literally explodes by dividing up into small units known as forks.

All these phenomena of natural erosion are collectively referred to as "weathering". If we add that water always accentuates the effects of "weathering", we might think that only short hair has any chance of being beautiful. Which is clearly not the case! Cosmetics exist to help the hair defend itself. Since the tissues that created it provide no support, it can only count on external elements to provide it with protection. However, hair products were for a long time only beauty products taking care of the hair's superficial appearance. Damaging them further just by colouring them. But this now belongs to the past. With the contribution provided by carefully developed molecules such as ceramide R, quality products now bring beauty and good health to the hair.

Cosmetics also provide remedies for other hair dysfunctions, quite independent of its cuticle.

  An excess of sebum



This is the case of greasy hair. Hair is naturally lubricated by a thin layer of sebum, produced by the sebaceous glands. This sebum is essential to provide the hair with protection, flexibility and shine. But under the influence of hormonal factors, the production of sebum can become abnormally high.

The hair then becomes greasy, getting dirty faster by attracting impurities from the surrounding air. The way a shampoo generates foam is a good indicator of the hair's greasy state, since an excess of greasy substances will prevent it from developing normally.

  Scalp problems


The presence of dandruff is also associated with the amplification of a natural phenomenon. For, like all the cells of the epidermis, scalp cells are constantly renewing themselves. Day after day, the oldest cells individually separate from the surface of the skin quite invisibly: this is ordinary desquamation .

But excessive quantities of a micro organism, "malassezia ovalis", naturally present on the scalp, can upset this function by accelerating the epidermis's renewal process. The cells therefore come to the surface of the scalp in groups before separating from it - and these are the particles of dandruff. The appropriate hair care products progressively limit the proliferation of the micro organisms responsible for this excessive desquamation.

  Unwanted guests


In another field, the scalp is also a favourite home for head-louses. Feeding on blood, this parasitical insect is totally at home in contact with the scalp, firmly gripping onto the base of a hair. Here, benefiting from the shelter, head-lousesdevelop and reproduce in the form of nits.

The cause of unbearable itching, they are easily eliminated by means of the appropriate anti-parasite treatment.

  Tics


Finally, and coming back to the hair itself, we should note that it can have an unexpected aspect when it falls victim to a fracture along its length. While transversal fractures are extremely common since they are produced every time a hair breaks, longitudinal fractures are rare.
Of course, made more probable by natural erosion, they are often the result of hair pulling tics (Trichotillomania ). This describes the tendency certain people have to constantly manipulate their hair, pulling it and rolling it around their fingers, or even pulling strongly on whole locks. Frequent among children, and often only temporary with adults, this tic is however medically classified as a Compulsive Obsessional Disorder.




WELCOME
PORTRAIT OF AN UNKNOW ELEMENT
LIVING AND RELIVING
AMAZINGLY NATURAL
SO STURDY AND YET SO FRAGILE

UNEXPECTED PROPERTIES OF HAIR

BEAUTY MACHINES

RESISTING A HOSTILE WORLD

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INFINITE TRANSFORMATIONS
THE HAIR A SCIENTIFIQUE ENIGMA
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