Your Hair: Dead or Alive?
Do you have dead hair? Yes and no.
Technically, the hair outside of your scalp isn’t physically alive: It has no blood, nerves, or muscles. When you cut it, it doesn't cause pain, and it doesn’t bleed. But healthy hair is remarkably resilient. It can be stretched up to 30% of its length, can absorb its own weight in water, and can increase its diameter by 20%. We can change its color and shape, curl it, wash it, brush it, set it, pull it, and rub it. And it still shines and moves beautifully .
Hair is composed of keratin, a fibrous protein. And its built from cells similar to our skin. The hair shaft consists of three layers: the outer cuticle, composed of overlapping layers, like fish scales; the cortex, comprising the hair’s main bulk and color; and the medulla, a thin core of transparent cells and air spaces.
We are all born with a specific number of follicles, and every follicle grows a single hair at an average of about half an inch a month. In fact, hair grows faster in summer than in winter. A hair's normal growth phase lasts between three to five years. After a short resting phase, the hair will normally fall away. The follicle then lies dormant for three months then the cycle repeats itself. Each follicle has its own independent cycle. And most of your hairs are in the growth phase at any given time.
The average head consists of 120,000 hairs. Blondes tend to have more, redheads fewer.
We could go on forever about the fascinating state of your hair. It truly has the power to transform us. And we never get tired of transforming it!