One hair... some hair
On average, each person has between 100 000 to 150 000 hair on their head. This amount of hair can vary depending on certain criteria such as gender, ethnic origin, age and especially the color of hair.
The color of hair
• Blond, light brown hair has on average 140 000 to 150 000 hair.
• Dark, dark brown, black hair has on average 100 000 to 110 000 hair.
• Red hair has on average 75 000 to 90 000 hair.
There are different colors of hair: blond, white, light or dark brown, brown, black, red...But also different types of hair: thick hair, thin hair, straight hair, frizzy hair, wavy hair, curly hair...There are thus as many types of hair as human ethnic groups in the world. We can also notice that the type of hair varies according to continents.
Haircuts vary over times and customs. Men have a tendancy to have short hair whereas women prefer to have it long or medium lenght. However, trends evolve rapidly and we can observe a turnaround of the situation as we see today some men having longer hair and some women having shorter hair.
Hair is composed of two distinctive parts. A visible part which is the shaft and one buried part which is the hair follicle. It is within this hair follicle that hair develops. Hair is essentially composed of keratin, which is reponsible for solidity. Hair also contains water, fatty acids, zinc, vitamins and melanin.
Hair is a living part of the human body. As such, hair is going to be born, live and die following the rules of the hair cycle. This cycle lasts on average 3 to 4 years in men and 3 to 7 years in women. During a life, each hair is going to renew itself about 20 to 25 times.
So each hair is going to live its own cycle, its own rhythm of «growth/fall».
The hair cycle takes place in 3 steps
The anagen phase
It is the growth phase of the hair. During this phase hair is going to grow from the hair follicle. Hair is going to grow about 1cm every month. This phase concerns 85% of hair.
The catagen phase
It is the resting phase of the hair. During this phase, hair no longer grows, the hair follicle is resting. This phase concerns 1% of hair and is going to last between 2 to 3 weeks.
The telogen phase
It is the hair loss phase. During this phase hair is literally expelled from the scalp. The telogen phase concerns 14% of hair and lasts about 2 months.