We cover many topics on hair loss for our clients in our writings, but I don’t recall anyone asking us about the life cycle of a hair. Many of our clients didn’t even realize that there is such a thing as a hair growth cycle. Although this is a very complex subject with many moving parts, we will break it down as best we can to understand the basics of what is involved.
Hair grows from the follicle which is located in the dermal layer of the scalp referred to as the Dermis, as seen in the diagram below. Each hair receives nutrients, necessary for healthy hair growth, from blood vessels that are located at the base of the hair follicle. Without a steady blood supply and ample oxygen, the hair will begin to degrade over time.
Clients that are under a great deal of stress often see their hair degrade due to these constricting blood vessels which restrict the amount of blood supplied to the scalp.
Each hair on the head goes through a cycle which includes four stages…anagen, catagen, telogen and exogen stage.
Anagen (Growth Phase) – This is the active growth phase which can last from 3 to 6 years. We like to see about 85 to 90 percent of the hairs in this stage at all times.
Catagen (Transition Phase) – This is the transition phase that can last about two weeks. In the stage the hair follicle shrinks and detaches from the dermal papilla.
Telogen (Resting Phase) – This is the resting phase which can last up to three months. It’s normal to see 10 to 15 percent of hairs in this phase at any time. While the old hair is resting, a new hair begins to grow from the dermal papilla.
Exogen (New Hair Phase) This part of the resting phase is when the old hair sheds and the new hair continues to grow and enters back into the Anagen Phase.
At Hair and Scalp Wellness we have a high-power microscope which we use to examine the scalp and determine what hairs are is what stages of the hair loss cycle. We often see clients with 20, 30 and even 40 percent or more of the hair in either the Catagen or Telogen phase. With this large percentage, clients will certainly see more scalp than normal causing them distress and reason to seek help. Many people will lose a great percentage of their hair before the decide to take action.
If you see your hair looking anything other normal for you… don’t wait. It is much easier to hold onto the hair you have than try to regrow the hair that was lost.