5 Phases of Hair Cycle
Hair from our scalp grows continuously in a series of phases. In order to achieve healthy gorgeous hair you must learn the 3 cycles that takes place in order for hair growth to occur.
Hair is composed of strong structural protein called keratin. This is the same kind of protein that makes up your nails and also the outer layer of your skin. Each strand of hair consists of, three layers
1. The innermost layer or medulla which is only present in large thick hairs.
2. The middle layer known as the cortex. The cortex provides strength and both the color and the texture of your hair.
3. The outermost layer known as the cuticle. The cuticle is thin and colorless and serves as a protector of the cortex.
Hair Growth Cycle
Your Hair follicle is a skin organ that produces hair. Attached to the follicle is a sebaceous gland. This is a tiny sebum-producing gland found everywhere except on the palms, lips and soles of your feet. The thicker
the density of your hair,
the more the number of sebaceous glands that are found.
The normal hair growth cycle is stimulated and maintained by the release of hormones that are targeted at the hair follicles. These hormones keep the growth cycle on track and allow for consistent hair growth. Hair follicles grow in repeated cycles. One cycle can be broken down into three phases
1. Anagen Phase
Anagen is the growing phase of the hair follicles. The cells in the root of the hair divides rapidly, adding hair to the shaft. The growing phase of the normal hair growth cycle is responsible for producing new hair and allowing continued lengthening of that hair.
In this cycle hair is produced at the root and growth is maintained through the blood vessels, which feed the hair strand its nourishment. Hair grows about 1 cm every 28 days and stays in this active phase of growth for approximately 2–8 years. At any given time about 90% of the existing hair follicles are engaged in this phase.
The amount of time the hair follicle stays in the anagen phase depends on the individual. Their intake quantity of
hormone levels, and other physiologic and pathologic factors goes into effect.
2. Catagen Phase
Catagen is a short transition stage (aprox 2-4 wks)that occurs at the end of the anagen phase. A club hair is formed when part of the hair follicle comes in contact with the lower portion of the hair shaft.
3. Telogen Phase
Telogen is better known as "the resting phase". Once a hair follicle enters the resting phase its function is to maintain the existing hair strand at the existing hair length. During this time the hair follicle still receives nourishment but is in the process of preparing for hair strand shedding.
The resting phase of each hair follicle lasts an average of 2-4 months after which time the hair strand is released so the follicle can prepare for new hair growth. About 5% of the hair follicles in the scalp are engaged in the resting phase of the hair growth cycle.
Apoptosis(major destruction)takes place at the lower end of the follicles and hair shrinks to about 1/6 of the normal length while the lower part is destroyed and the dermal papilla breaks away to rest below. Once the resting phase is complete the shedding phase begins.
4. Exogen Phase
Exogen is also known as the hair shedding phase and "the last phase" of all hair growth cycles because no hair is visible from this point on. The average head of hair on a daily basis looses about 80-100 strands of hair.
Exogen deals mainly with the hair shaft base and not directly with the hair follicles. The details of the exogen mechanism are poorly understood, but it certainly influences the anagen phase.It is necessary to understand your hair and the normal process of hair re-growth which in turn will help you to understand any hair loss causes.
5. Kenogen Phase
The “kenogen” phase was termed to describe the gap between the hair cycle where the hair follicle remains empty after the telogen hair had been expeled and before a new anagen hair reappeared.
It is perfectly normal to observe kenogen in healthy skin and scalp, but in men and women with androgenetic alopecia the frequency and duration of kenogen have been reported to be greater.
By taking good care of your hair, with proper nutrition and natural hair care products you can help your hair to be in good health. Understand the natural cycles of hair growth and take care to maintain their structure and function without harming them.