Page 17 - HAIR COLOUR

The Human Hair Cycle.

What is the human hair cycle? And how does it vary from race to race?
As far as we know, the hair cycle does not vary from one race to another,
but it does vary between all humans. A human hair will grow from the
scalp, and continue to grow until it separates beneath the scalp; then it is
pushed out of the scalp by the new hair. (Fig 14.)

This separation takes place on a on a regular basis, for some people it can
be as often as every two years, whereas, others may take as long as six
years. This is what is known as the hair cycle.

In theory a person with a six-year cycle should be able to grow their hair
three times as long as a person with only a two-year cycle. However, if

the person with a two-year cycle grows three quarters of an inch a month,
and a person with a six-year cycle only grows a quarter of an inch a
month then the length will be the same.

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