Why is our hair so different?

It exist three main hair types, Asiatic hair whose structure is round and colour dark, African hair with an elliptic structure weakly flattened whose result is an anarchical growth which gives a tighten curls and a colour generally dark, and at last, hair of Caucasian type also called European, the unique to decline numerous colours variants going frond blond to brown, through red, its structure can be from straight to curled.

Hair belongs to hair system and was the object of only a few researches in relation with their importance so in different world cultures. Force or seduction emblem, however hair does not let indifferent and today, it is put at the honour and researches are made to improve its appearance which, as time goes by, is damaging. Because of exterior aggressivities such as pollution, UV, hair losses it splendour, in fact, visible part, said capillary fibre, is dead part of hair, root, magnificent « mould », gives life to hair, activity is incessant here.

A few verities incredible and surprising on hair.  They grow of about 1 cm a month, however, it is rare to see hair overtaking a life duration of 8 years and 1 metre of length. Nevertheless, each hair being unique, one can meet people with an incredible hair, the most long known measured 4.2 metres, tips were 35 years, incredible but not very practical, you will tell me, for everyday life. They are about 150 000 to recover our cranium of a diameter between 50 and 100 micrometres, that gives you 250 hair per cm2.

Despite the loss of about one hundred hair per day, each hair can support 100 g, that gives in fact a resistance of about a dozen tons for a complete hair, a similitude with spider’s thread, it is also very resistant. Concerning hair root, it is in the interior of the dermis, it is there that hair builds and takes its coloration. Hair growth varies with age and seasons. At the embryo step, dermis is building and hair follicle appears. Male hormones are known to 

slow down hair evolution, one can however it exists means to increase hair resistance and to intensify their  new growth.

 
In a life, a cycle of 25 hair growths whose duration life lasts about seven years and which will however be tributary from their environment and their carrier. Pollution but also alimentation and well-being of the human being will define hair health.

At any time, hair is interpreted like a code, as well as cultural as hierarchical or even religious. Modern times are not in rest and scientific progresses brought knowledge on the mystery emblematic that hair contains. Keratin, main compound of hair is a protein constituted by 18 amino acids whose certain split in the hair follicle whereas other will form pilar stem. It is in the interior of root that hair is constituted when it receives keratin, once at the outside, it will not receive anymore any contribution and becomes dead part, but the fact that hair grows by root and not by tip, it continues its growth in length.

Sebum is absolutely not an enemy of hair as one should think about it, it preserves its flexibility and its brightness bringing it a protector film. For its coloration, there are eumelanin which gives a dark coloration and phaeomelanin for its clear coloration which are at the origin of hair colour; it only represents 1 % of composition of it. One will find other substances in its composition as water whose it will keep mineral salts and other substances that it captures by blood vessels irrigation, making it an indicator on the ADN carrier.