Hair is actually dead material when it leaves it's root - otherwise it would hurt very much when your hairdresser works with his scissor. Most people know that, but do you know about these facts:
A blonde head of hair has usually much more strands than red or dark haired heads.
Hair consists mainly of keratin, which is also responsible for the elasticity of fingernails.
A single hair has a thickness of 0.02 - 0.04mm, so that 20 - 50 hair strands next to each other make one millimeter.
Hair is strong as a wire of iron. It rips after applying a force equivalent to 60kg, only after it stretched itself for about 70%.
Even on a good hair day, everyone loses at least 40 to 100 strands.
The average scalp has 100,000 strands, or just fewer than 1000 per square inch.
We are born with all our hair follicles. Some are programmed to grow pigmented hair (as on our scalp) up to 3 feet in length.
In America in '96, 38 million men and 19 million women experience common hair loss determined by heredity.
The trait for baldness can be passed down through paternal or maternal genes.
Hormone imbalance and crash dieting can trigger temporary hair loss.
Hair biology
![[Hair structure]](/0/images/all/up/20070704/11S5KU1J11025H1.jpg)
The root of a hair strand sticks in a bag in the skin. The strand is pushed out of this bag about 0.35mm per day, making an average growth rate of 1cm, or half of an inch, per month. The growth rate is however very much related to the individual person, his age, his diet etc.
Healthy hair has an average lifetime of 2-6 years. After a rest period of three months the single hair falls out, and a new strand starts to grow out of the bag. The lifetime depends on circumstances and person, too.
The lifetime of hair is responsible for the maximum of hair length you can have. Waist length hair takes about 6 years to grow out from a short hair cut, periodic trims included. If your hair has a life cycle of 2 years, you will never achieve a nice waist length mane.
Diet
The right food is important for your hair.
Without Vitamin A your hair becomes brittle, and abnormal dandruff can develop.
Without Vitamin B1 or B6 you can start to lose your hair.
Vitamin C stimulates the hair growth and regulates the generation of pigments in the hair strand.
Vitamin B12 supports feeding the root.
