Structure and Growth

Healthy Hair

Structure and Growth

Let's start with a brief exploration into the science of hair. This is the crux behind correctly and gently caring for our natural headdress. Read how a healthy hair is structured and what its life stages are.

How a hair is structured

The human hair consists of the hair shaft, the root and the bulb.

We normally only see and talk about the visible part of the hair, the hair shaft. It consists of three layers containing keratin: medulla, cortex and cuticle. The medulla is located in the center, around the medulla is a layer of keratinized cells, which is called the cortex. This fiber layer determines the firmness and elasticity of the hair and it also contains the color pigments. A cuticle layer around the cortex protects the hair like a pine cone. It is transparent and thin, and the color pigments shimmer through. If this cuticle layer is healthy, the hair has a smooth surface and reflects the light so it shines beautifully healthy. Keratin is extremely important for the healthy structure of the hair. If the hair is damaged by misuse or harsh styling you can give first aid with keratin-containing products, to smooth the outer cuticle.

The non-visible part of the hair, the hair root, is embedded in the skin. The hair shaft is in a kind of cone-shaped introflection of the skin (epidermis) inclined at an angle of around 75°.

The root of the hair ends with a tuberous thickening, the hair bulb. All the reproductive functions giving rise to the formation of the new hair occur inside the bulb.

How hair grows

Our hair undergoes a precise life cycle in an alternation of three different phases.

In the growth phase, or anagen phase, the bulb cells reproduce and a new hair shaft grows. This phase lasts about three to five years for men, six to seven years for women.

After the growth phase comes the transition phase, the catagen phase. The cells no longer reproduce, the hair bulb enters a resting phase and rises to the surface where the hair shaft stops its growth. This phase only lasts about two weeks.

In the resting phase, or telogen phase, the hair prepares to fall out. This takes about three months.

After the resting period a new growth phase begins and all three phases are repeated. When we reach 40, more and more of our hairs are in the resting phase, they grow back less often, fall out more easily, the hair shafts become thinner, the production of sebum reduces.

Did you know that humans have an average of 100,000 hairs on their head? The interesting thing is that this average applies to brown-haired people, while blondes have many more hairs (150,000), and black-haired people an average of 110,000. Red-heads have the fewest hairs – only about 75,000. Hairs grow about 0.3 mm a day, so up to 1 cm a month. Going through all three of the phases described above, one hair will live for about two to six years. About 60 to 100 hairs fall out every day.