Each person receives the main hair bulbs by his/her birth. The growth of the hair from the hair bulb is a continuous process with a speed of 0,3 - 0,4 mm per day or 1 sm per month. The growth is fastest during the spring and by the beginning of the summer. The head hairs have the longest phase of growth – from 2 till 10 years and are growing under angle of 31-59 degrees to the head skin. The phase of the growth of the moustache is from 4 till 14 weeks and of the eyelashes – 105 days.
The hair growth includes three phases, which duration is different and depends on the age and on the type of the hair bulb:
Anagen – phase of the producing of the hair;
Katagen – middle phase, where the kernel of the hair bulb becomes harder and turns to a “hair follicle”, which pushes out the hair;
Telogen – this is a phase, where the hair falls. These are the hairs that are falling by brushing or washing. By the end of its life the old hair lives together with the new one that begins its live from the same bulb.
It is normally that 50-100 hairs fall per day as the number of the head hairs is 100-150 000. If the hairs are thinner, they are more in number. The thickness of the hairs is different. By the European it is 0,04-0,06 mm.
By the black people the hair bulb has a spiral form and because of this the hairs are with the same form.