How many hair follicles does a human have?

Since the appearance of hair, in the development of body, there are distinguished:
- Lanugo intrauterine hair ;
- Vellus, hair covering the body of babies up to 6 months;
- intermediarie hair, up to 11-16 years;
- definitively hair, over 16 years.
On human bodies there are about 5 million of the adult hair follicles. To the men there are about a few hundred thousand more than in women. What differs greatly between the hairiness of the women and the men is thick, long hair and consistency, which are better represented in men. Only on the scalp are 250 000 - 500 000 hair follicles. Distribution of hair is not uniform, in the body that is 40-60 follicles / cm ², the scalp is of 200-400 follicles / cm ² and in the male chin reaches 900 follicles / cm ². The speed of hair growth is 0,1-0,5 mm / day, which is higher in women than in men, lower in the elderly and higher in warm seasons. Some hair follicles are permanently lost as we grow older. And hair structure is modified, it becomes thinner and less elastic, lose it's pigment and density changes significantly. It is said that a daily loss of 100 hairs enrolls in normal limits. Making a calculation how many hairs we lose each year we deduct that in 10 years we would lose all hair if it won't be regeneration process.
Regeneration also gain a new connotation to more advanced ages, being slow and incomplete.