Phases of hair growth

/Phases of hair growth
Phases of hair growth2018-05-14T17:57:58+02:00

Hair is growing in cycles and it is a slow process. For one cycle to complete it can take between 3 to 5 years.
The three stages of hair growth:

anagen-catagen-telogen

Anagen

This “active” phase of the growth cycle is also the longest. During the course of three to five years the hair will grow longer every day.
Once this part of the cycle is completed the follicle will enter the so-called catagen phase:

Catagen

The catagen phase of hair growth lasts for a few weeks. This is the part of the hair growth cycle in which the bottom of the hair follicle, normally referred to as the “bulb”, will shrink and detach from the blood supply in the scalp. While it would be logical to assume that the follicle is now dead, since it does not have a blood supply, this is not so. It is simply going into a state of rest.

Telogen

The subsequent phase is the so-called telogen or “resting” phase of hair growth and it is this part that can cause anxiety for many people. When the hair transitions from the catagen phase to the telogen phase, the follicle will release the hair shaft and the hair will fall out of the scalp.
However, usually the follicle will regenerate, reattach to the blood supply in the scalp and form a new hair shaft. The cycle then repeats itself, unless it is disrupted, which is when we experience thinning of the hair or even balding.

It is perfectly normal and no cause for concern that some 10% to 15% of all hair is in the telogen phase, where between 100 and 200 hairs will be shed every day.

By the time you have noticed your hair is thinning you have already lost approximately 50% of the hair in the visibly affected area. 50%!!!

How can this be? It all has to do with visual perception.
Often the length of the hair covers areas affected by hair loss, at least up to a point. However, once a certain threshold is crossed then the length can no longer compensate for the reduction in density and the hair loss becomes visible.

Hence, in most cases excessive hair loss is barely noticeable until the thinning has become quite severe.

Androgenetic alopecia is caused  by a hormone known as dihydrotestosterone (DHT). This hormone attaches itself at the cellular level to the bulb of the follicle and affects how the follicle receives nutrition. Over time the follicle will not recover from the telogen phase as robustly as it did when it was unaffected by DHT. The anagen phase of growth is shortened so the hair shaft cannot grow as long nor does it mature to its full diameter. This is known as hair follicle miniaturisation.

In the world of hair loss and restoration, healthy hair is being referred to as “terminal hair”, whilst the affected by DHT are called “miniaturised hairs”.

First signs include that your hair may not grow as long as it used to be. You may even notice it when styling your hair, that it fells somewhat thinner. However, by the time you will notice this, you have most probably already reached an advanced stage of hair loss. Hence you best approach a trained professional to help you learn if you are affected by hair follicle miniaturisation. Experts include dermatologists, hair transplant physicians or trained staff working in specialised hair transplant clinics.
With the help of specialised microscopes they can find out if your hair follicles are miniaturising or if something else may be affecting your hair to have changed in appearance.

However, by the time you feel that such a consultation may be necessary, the effects of DHT have usually already reached an advanced stage for them to be visible. Hence, if you feel your hair is thinning or not as voluminous as it previously was and has changed in texture, you might want to see an experienced hair restoration specialist to get you started on an individual hair restoration plan.