Hair Growth Cycle: Understanding The Structure Of Your Follicles

Have you ever wondered how the hair on your scalp appears, grows or falls out? Understanding your natural hair growth cycle [1] is the primary aspect of your journey to combat hair loss.

"According to Ayurveda, hair is an accessory tissue of Asthi dhatu. All body tissues follow a simple cycle of growth, rest and death. This tissue is then replaced by a healthy new tissue. Likewise, hair undergoes a natural cycle of growth, rest and fall, only to be replaced by a new healthier shaft," says Dr. Zeel, Chief Ayurvedic Doctor at Vedix.

In this article, let’s dive deep into different stages of hair growth while understanding multiple factors that disturb this natural cycle, causing abrupt hair fall.

Highlights:

• How Does Your Hair Grow?
• Structure Of Hair
• Does Your Hair Go Through Cycles?
• Stages Of Hair Growth Cycle
• Is It True That Your Hair Changes Every 7 Years?

How Does Your Hair Grow?

• Your skin consists of little pocket-like structures called ‘follicles [2]’.
• Each follicle has a root, which is made up of protein cells at the bottom, from where your hair begins to grow.
• The blood vessels in your scalp supply essential nutrients to the roots, which help it synthesize hair.
• As the hair grows, it gets pushed up through the layers of the skin and pokes out.
• The oil glands attached to the follicles provide natural lubrication, softness, and shine to your hair.

Structure Of Hair

Your hair structure can be divided into two parts:

1. The structure inside the follicle.

2. The structure of the hair shaft that is present above the epidermis.

1. Structure Inside Follicle

A. Hair Bulb

It is the lowest part of your hair strand, which lies inside the follicle. The club-shape of the hair bulb helps it to get locked by the dermal papilla.

B. Dermal Papilla

It is the cone-shaped elevation which is present at the base of your hair follicle. It fits into the hair bulb and holds it. Dermal papilla[3] is connected with the blood vessles.

C. Arrector Pili Muscle

It is an involuntary muscle present at the base of the hair follicle. You get goosebumps when arrector pili contracts.

D. Sebaceous Glands

These are the oil glands that are connected to the hair follicles. Sebaceous glands secrete sebum for your hair.

2. Structure Of Hair Shaft

A. Cuticle

IIt is the outermost layer of your hair strand. It acts as a protecting layer to the inner hair structure. A strong and integrated cuticle layer imparts shine and smoothness to your hair.

B. Cortex

It is the middle layer of the hair strand. The protein present in the cortex is responsible for the elasticity and color of your hair.

C. Medulla

It is the innermost layer in the hair strand. In general, it exists only in thick and coarse hairs. The purpose of medulla has not been identified yet.

Does Your Hair Go Through Cycles?

The hair growth happens in a cyclical process in your hair follicles. The cycle consists of four phases-anagen (growth), catagen (regression/transition), telogen (rest) and exogen (shedding). The whole cycle lasts for a few years for each of your hair strands on the scalp.

Stages Of Hair Growth Cycle

As per the ancient Ayurvedic system, every human is a congregation of three vital life energies: Vata, Pitta and Kapha. While the unique constitution levels of these three doshas determine the unique Prakriti of the person, it is believed that each dosha has a major influence on the Prakriti for a specific period in the lifetime of an individual.

Kapha dosha is believed to have a dominant role from childhood to adolescence. i.e, until a person reaches 16 yrs of age. This can be considered as the Kapha Kala of life. During Kapha Kala, your hair will have the most convenient ambience to remain healthy and strong.

Pitta dosha is believed to have a major role from adolescence to old age. i.e, until a person reaches 50 yrs of age, which can be considered as Pitta Kala of life. Similarly, Vata dosha plays a predominant role in old age, i.e, from 50 yrs to the end of the lifetime, called Vata Kala. Most of the hair related problems and hair loss are observed during Pitta and Vata Kala of human life.

A person can also have imbalanced Kapha dosha, which causes conditions like severe dandruff, hair loss, and other scalp infections.

Now, let’s understand the different stages of hair growth and their correlation with Ayurvedic Kalas [4].

1. Anagen Phase

The phase in which your hair starts growing from the follicle root is called the Anagen phase. During anagen, the stem cells of the dermal papilla multiply to produce hair protein and fibers.

The span of the anagen phase lasts from 2-7 years depending upon your Prakriti (genetics) and various internal and external factors, while it determines the length of that hair strand.

In Ayurvedic terms, the anagen phase can be correlated to Kapha Kala during which your hair grows steadily for a longer period. As you age, the transition of Kapha and Pitta Kala occurs, which results in a decrease in the span of the anagen phase.

Anagen Effluvium

Sometimes, external factors like chemotherapy drugs, radiotherapy, oral contraceptives, vitamin A poisoning, chronic infections, other chemicals, etc. can result in an abnormal ending of the anagen phase. This means your hair starts to shed when it is still in the anagen phase. This condition is termed as ‘Anagen Effluvium’.

"According to Ayurveda, conditions like Indralupta (alopecia areata), Darunak (dandruff), Dadru Kushta (tinea infections), Eka kushta (psoriasis), etc. can also lead to anagen effluvium. This is due to high imbalances occurring in the dosha constituency of an individual, " says Dr. Zeel.

Although severe hair loss is observed during anagen effluvium, hair starts to regrow again naturally after a few months in most of the cases.

2. Catagen Phase

By the end of the anagen phase, your hair strand enters the catagen phase naturally during which it gets detached from the root. This is the transition or regression phase of your hair growth which can be correlated to Pitta Kala in Ayurveda. During the catagen phase, hair follicle renews itself by shrinking to 1/6th of its length and the papilla rests.

Though the hair strand gets separated from the dermal papilla and stops receiving the nutrients, it does not shed off in the catagen phase as the shrunk walls of the hair follicle anchor the shaft part of the strand temporarily. And, this phase lasts for about 2-3 weeks in general.

3. Telogen Phase

By the end of the catagen phase, your hair strand becomes a club and the dormant resting phase, telogen begins. This phase is closely related to Vata Kala in Ayurveda. Telogen phase lasts for 3-5 months during which a new hair emerges from the roots and slowly pushes up the previous club hair.

Telogen Effluvium

Sometimes, conditions like physical or mental stress, hormonal imbalances caused by pregnancy or menopause, protein deficiency, etc. can result in the hair prematurely entering the telogen phase, and eventually shed off. This kind of hair loss is called Telogen effluvium or Khalitya [5] in Ayurveda. Telogen Effluvium mainly occurs due to an imbalance in Pitta and Vata doshas in an individual.

4. Exogen Phase

It is the last phase of the hair growth cycle when the hair strand completely detaches from the scalp and sheds off. This is the hair that you notice falling out while you comb or brush every day as around 50-100 strands undergo exogen phase daily naturally.

Is It True That Your Hair Changes Every 7 Years?

Typically, hair growth lasts for about 4-7 years. However, it only happens for the first 2-3 cycles. As discussed above, with growing age, the duration of anagen phase shortens and the hair which grows back is thinner than previous hair. This can be related to the altering influence of different doshas as you grow.

At any point, you need to evaluate if you have normal hair fall caused by the natural hair growth cycle and understand your dosha imbalances to check if you are going through anagen effluvium or telogen effluvium.

"Ayurveda bestows different dosha specific herbal formulations which target the root cause of your hair loss while keeping your dosha levels in equilibrium," says Dr. Zeel.

The Last Word

Daily, it is quite normal to lose about 50 -150 hair strands as they reach the end of their resting phase. Hence, you need not panic if you notice some hair fall while you comb or brush daily. However, keeping your doshas in balance with holistic Ayurvedic hair care, diet and lifestyle helps you maximize the duration of the anagen phase. Thus, you can prevent aggressive hair fall. At Vedix, we analyze your dosha levels and customize the Ayurvedic hair care regimen that targets the root cause of your hair fall.