What is Hair Made of?
The key component to hair is a protein called Keratin. Keratin is a very strong building block protein that is also very similar to the key components of skin and nails. Keratin is the foundation and gives structural strength to hair. Each hair is made up of 3 layers.
- The Medulla or innermost layer.
- The Cortex which is the middle layer of a hair. The texture and color of each hair is contained in the cortex. The cortex is also the strongest part of the hair.
- The Cuticle is the outer layer of each hair. The main function of the cuticle is to protect the follicle.
The root lies below the surface of the skin and is encapsulated by the follicle. The follicle base contains the growth cells or the dermal papilla. Nourishment is carried through the bloodstream and directly feeds the dermal papilla at the base of the follicle. Blood-flow and nourishment are crucial to good hair growth. Whether you are looking to grow healthy hair or stop hair growth permanently, the dermal papilla at the base of the follicle is key. Proper blood flow and nourishment can keep your follicles healthy and producing hair while damaging the follicle and dermal papilla through IPL, laser or electrolysis will stop the follicle from producing hair.
The cycle of hair growth
The hair growth cycle is in a continuous loop. There are three stages in the growth cycle. These three stages complete and then repeat. The three stages in the growth cycle of a hair are:
- Anagen – Growth Stage
- Catagen – Transitional Stage
- Telogen – Resting Stage
Every individual hair goes through the same growth cycle independently. This means that all hairs are somewhere in a growth cycle but not in the same stage at the same time. This is why hair removal treatments take some time. Most hair removal treatments effect hair in the first stage of growth. Multiple treatments are needed in order to catch each hair in the first stage or Anagen stage.
Anagen – Growth Stage
The anagen growth-stage can last anywhere from 2 to 6 years. This is the longest stage of the three. At any given time some 85% of your hair can be in the anagen stage at the same time. During the anagen stage the hair is attached to the root and is very much alive and growing. Over the life time of a hair, it can grow up to a meter (sometimes longer) at the rate of about 10 cm a year.
Catagen – Transitional Stage
The catagen stage is called the transitional stage because the hair structure changes from alive to dead. In this stage the hair separates from the root and dermal papilla. The follicle shrinks and the dermal papilla temporarily becomes dormant. Blood flow and nourishment is cut off from the upper structure of the hair and is considered dead for all intents and purposes.
Telogen – Resting Stage
During the telogen stage the hair although dead is still attached to the follicle but not growing. This stage usually lasts 5 to 6 weeks. The dermal papilla is still dormant and resting while the rest of the hair is now preparing to be expelled from the body. The end of the telogen stage is the rebirth of life in the hair follicle. The dermal papilla is rejoined with the base of the follicle and the dermal papilla comes out of its resting or dormant state. The new hair growth marks the beginning of the anagen stage and a new growth cycle starts again. As a new hair is formed the old dead hair is pushed out of the follicle. This completes the growth cycle. Now the entire process will repeat again.