What is the Role of the Hair Follicle?
For someone wanting to grow a healthy head of hair, it can be important to know the purpose and function of a hair follicle. This vital structure produces and holds a strand of hair in place on the skin. The guide below will answer the question, “What is the role of the hair follicle?”
- What is a hair follicle?
- The Influence of Hair Follicles on Properties of Hair
- What Causes Hair Follicles to Die?
- How Do You Stimulate Hair Follicles to Grow?
- What is the White Bulb Around Shedding Hair?
What is a hair follicle?
A hair follicle is a tunnel-shaped structure grounded in the deep dermal tissue, extending up to the outer layer of skin. The average depth of a hair follicle on the scalp is 4.16mm. The base of this structure is held in place by sebaceous glands and a muscle called the erector pili.
This structure also includes sensory fibers at the base and shaft, allowing for important sensory feedback. While the majority of nerve fibers surrounding a follicle are sensory, the autonomic nervous system can also stimulate the erector pili muscle when necessary.
In addition to nerve fibers, the hair root is also encircled by blood vessels that provide vital nutrients for hair growth.
A short overview on the hair’s life cycle
The role of the hair follicle is to grow and anchor hair into the skin. The complete hair cycle takes place within the follicle and the steps are described below:
- Anagen phase : This is the growing, or proliferation, of a new hair strand. The timespan of this phase can vary depending on the location in the body. For hair on the scalp, it can take anywhere from 2-6 years for this phase to complete. The inferior segment of the hair follicle is only present during the anagen phase and disappears during subsequent phases. The hair is produced through cells signalled to proliferate, differentiate, and grow up the shaft.
- Catagen phase : The purpose of this phase is to transition from the growing to resting phase. It is the shortest phase and allows for the cells to cease division and for the inferior segment to dissipate. The base of the hair strand converts to a club hair with a hard, white nodule on the end.
- Telogen phase : This is the resting phase that holds the club bases in place. Each hair is only held for around 100 days on the scalp. After the 100 days, the hair is shed so the growing phase can begin again.
On average, 85-95% of all hair strands are in the anagen phase. Each hair grows around 1cm per month. The loss of hair in the telogen phase is ongoing. Each person sheds around 100 hairs per day. The difference in the colour and shape of each hair strand is attributed to properties of the hair shaft.
The Influence of Hair Follicles on Properties of Hair
Genetic influence leads to the shape of follicles and contribution of melanin, or colour composition, for each strand of hair. Curly hair is produced by an “S” shaped follicle created during the embryonic stages of development.
Straight hair strands are produced by a straight follicle. These shapes can undergo slight changes every few years, but the overall frame will remain the same. Factors such as hormones, drugs, vitamins, and chemical treatments can influence the shape of a follicle.
The role of keratine in texturing the hair
A minor role in the overall texture of hair also comes from the chemical composition of keratin, the protein that makes up hair. Curlier hair will contain more disulphide bonds between the individual components of keratin while straight hair contains a smaller number of these bonds.
The colour of hair is determined by the pigmentation of the hair follicle. Cells called melanocytes transfer pigment to keratinocytes, or the protein cells that comprise hair strands, leading to a pigmented hair shaft.
This process occurs during the anagen, or growing, stage of the hair cycle. There are two types of pigment, eumelanin and phaeomelanin. The eumelanin produces darker hair colours such as black or brown. Phaeomelanin leads to red hair. Grey hair is caused by an overall reduction of melanin in the hair shaft.
What Causes Hair Follicles to Die?
Male pattern baldness, also known as androgenic alopecia, or other autoimmune conditions that lead to balding, first begin the process of hair loss with a shrinking of follicles.
This is called miniaturisation. The decrease in the size and length of the follicle draws the hair bulb away from the natural blood supply, which ultimately results in the death of the hair follicle.
DHT and male pattern baldness
Miniaturisation in male pattern baldness is thought to be caused by an excess of the androgen dihydrotestosterone (DHT). The DHT attaches to androgen receptors in the follicle.
Through an unknown method of genetic activation, this binding of DHT to androgen receptors leads to follicular miniaturisation. A smaller follicle will produce, thinner, shorter strands of hair.
If you can see hair growth, even if the hair is fine and difficult to see, the follicle is not dead. Often, this stage of “peach fuzz” signifies the follicle could be close to death, but has not yet ceased to produce new hair. Once a hair follicle has died, it will not grow back through natural processes.
The hair transplant as the only permanent solution
There are studies being conducted at Columbia University to produce the regrowth of hair follicles using stem cells. This technique has not yet been tested in humans, but has resulted in new hair growth in areas of previously bald skin in mice. The only other way to create new growth from dead follicles is through a hair transplant, also known as “plugs.”
How Do You Stimulate Hair Follicles to Grow?
If you are concerned about hair loss, it is best to prevent this process by maintaining and promoting hair growth in follicles that have not yet miniaturised. This can be done through a balanced diet including vitamins A, C, D, E, zinc, iron, omega-3s, and proteins.
In addition, reducing the use of hot tools and cleansing your hair appropriately can alleviate hair damage. A specific treatment to clean and balance the pH of hair follicles is apple cider vinegar. Adding apple cider vinegar to your hair routine can promote a healthy scalp, stimulating hair growth.
What is the White Bulb Around Shedding Hair?
Noticing a white bulb around the end of a hair that has shed can be a natural occurrence. If this is experienced in excess, it might signify hair loss due to a temporary condition called telogen effluvium.
This is not necessarily an indication of permanent hair loss, such as with androgenic alopecia. The white substance is a part of the lining of the follicle called the root sheath. This will only come out if the strand of hair is shed during the telogen phase of the hair cycle.
If a hair is intentionally plucked, it may contain a white bulb at the end. This hair pulled out of the follicle will grow back the majority of the time. It is extremely difficult to pull out a completely intact hair follicle. If the entire follicle is removed, hair will not grow back. However, this is a very rare occurrence.
The hair follicle is a vital part of overall hair health and growth. This structure forms a tunnel deep into the skin, proliferating new hair growth through the shaft and past the scalp, holding each hair strand in place. There are many phases of hair growth, all of which take place in the follicle.
In certain conditions such as male pattern baldness, the follicle can miniaturise, eventually leading to death and lack of new hair growth from the follicle. As of today there is no permanent solution to this form of hair loss apart from a hair transplant.
Do you have more questions or are you suffering from hair loss issues ? Then feel free to to contact our friendly team that will answer all your queries. Furthermore they can also offer a free and non binding hair analysis.
So don’t hesitate if you want to benefit from Dr. Balwi and Elithairtransplant’s expertise for a successful and affordable hair transplant in Turkey !
Free hair analysis from Europe's No.1
Our team of experts analyse your hair to provide you with a no-obligation quote. Use our free hair calculator to submit your requirements - it only takes 2 minutes!