For first-timerFundamental hair knowledge
1Hair Structure
The hair shaft consists of three main parts.

2Asian Hair and Caucasian Hair
Item | Asian | Caucasian |
---|---|---|
Number of hairs | Approx. 100,000 pcs. | Approx. 140,000 pcs. |
Hair thickness | Approx. 0.08 mm (80 μm) | Approx. 0.06 mm (60 μm) |
Hair diameter index * 1 | Approx. 80 - 85 | Approx. 60 – 65 |
Growth speed | Approx 1 cm / month | |
Hair cycle | Men : 3 – 5 years, Women : 4 – 6 years | |
Hair loss * 2 | Approx. 50 to 150 pcs. / day |
*1 Index referring to the shape of hair cross section. The closer to 100 the more round the shape. (Hair diameter index = minor axis / major axis x100)
*2 The amount of hair lost fluctuates depending on individual differences, age and season.
3Hair Color
The natural hair color is largely determined by the amount of melanin contained in the cortex. * Black hair contains large amounts of melanin, however hardly any exists in gray hair. The color of melanin contained in the cortex will become the color of the hair since the cortex is clear.

* Eumelanin (brown-black) and Phenomelanin (yellow-red) exist within melanin and the color of hair is mainly determined by eumelanin. The more eumelanin exists, the more black hair will be.

Gray hairs occur when the hair cannot create any more melanin. It is said that the reason melanin stops being produced is not only due to age but also due to heredity, stress and disorder of eating habits.