If you’re here, it’s most likely because you’re interested in learning how you can grow healthy natural hair. Maybe you’ve tried everything under the sun, but you’re not getting the desired results. Also, you’ve most likely spent money on products that left nothing but a dent in your wallet and an all too familiar look of disappointment on your face. But I have good news and bad news. The bad news is that hair is more complex than most people think it is. Because most people aren’t well knowledgeable in hair science, they take whatever hair advice they can get without thinking twice about it or doing their due diligence of research. The good news is that there’s a wealth of well researched hair information that has been scientifically proven to be imperative to achieving excellent hair growth. Two crucial pieces to the natural hair growth puzzle that are often overlooked are a deep understanding of hair anatomy and an even deeper understanding of the hair growth cycle.
- Hair Anatomy
As I mentioned, hair is complicated. When most people think of hair, they think of the shaft (the part that extends from the skin) without really giving much thought to where it comes from. Hair has two explicit structures: the shaft and the hair follicle. Follicles lie beneath the skin surface, and lay the foundation for the density and rate of growth for your hair. If hair were a house, the follicles would be the foundation, invisible at the surface yet holding the integrity of the entire structure. Below is a close-up showing how everything is tied together.
On the left is a cross-sectional view of the hair shaft in relation to the layers on the skin. The outermost layer of the skin is the epidermis, and directly beneath that is the dermis. At the very bottom is the subcutaneous layer, which is made up primarily of fat and connective tissue.
On the right, is an up-close view of a hair shaft, with the different layers showing.
Without getting too much into the science of hair, I’d love to shed some light on what these various structures are and why they’re important when it comes to growing healthy natural hair, regardless of length.
- Blood Vessels- tiny blood vessels that bring oxygen, hormones and nutrients to the hair and remove waste material from the hair.
Tip: In your haircare routine, you want to include healthy habits that encourage circulation to your scalp. This may include scalp massages and warm towel treatment to your scalp. Also, exercise may not seem like the obvious choice, but it’s a surefire way to increase circulation in general.
- Nerves: also called root hair plexus, is a group an nerve endings that sends and receives nerve impulses to and from the brain when hair moves.
- Dermal papilla: (plural: papillae) provides nutrition by extending from the dermis into the hair bulb.
- The hair bulb : a structure at the bottom of the hair follicle itself , and is responsible for sprouting the hair shaft up the follicle, past the scalp. This bulb is the living part of the hair, with remarkable rates of cell division.
- The sebaceous gland : a structure that produces sebum, which conditions hair and skin.
Tip: If you’ve ever wondered why the natural hair community unanimously agrees that sulfate-free shampoos are the way to go, it’s because sulfates acts as surfactants (think of detergent) and wash the sebum away. This leaves both your hair and scalp dry.
- The hair shaft: is made of a hard protein called keratin and is made of three layers as shown in the right part of the diagram above: the medulla, the cortex and the cuticle. It must be noted that the shaft is made up of dead protein, so the hair shaft is not a living structure.
- Medulla: the innermost layer of the hair shaft. This layer is only present in thick hair (example, scalp hair) and not in thin hair such as that found on the stomach. There’s still debate about the function of this layer, which is why it’s sometimes referred to as “the riddle in the middle.”
- Cortex: this is the second layer and makes up the majority of the hair shaft. It also contains most of the hair’s pigment , giving hair its color. In this layer, the amino acids that make up keratin ( cysteine) are bonded together buy what are called disulfide bonds. These bonds are what determine the shape, stability and structure of the hair shaft.
Tip: Some doctors recommend taking cysteine as a supplement to encourage hair growth. Of all amino acids, it is the biggest component of keratin. You can get it naturally by consuming protein-rich foods. If you’re vegan or vegetarian, you may need to take a supplement, but always consult with your physician.
- The cuticle: this is the outermost layer of the hair shaft and is made of flattened, overlapping, cuticle cells. The normal cuticle has a smooth appearance, allowing light reflection and minimizing friction between hair shafts. This layer is responsible for the luster and texture of the hair.
Tip 1: When brushing/combing your hair, pay attention to the friction you feel when you run the brush/comb through your hair. Too much friction leads to breakage, so always go for a comb size or brush size the minimizes friction.
Tip 2: Moisture aka water is a great lubricant, reducing friction between hair strands. That’s why it’s important to include a moisturizer is your haircare regimen. More on this another post.
Now that you have great understanding of hair anatomy, let’s take a closer look at how exactly hair grows.
The Hair Growth Cycle
The hair growth cycle is made up of four stages: anagen, catagen, telogen and exogen. This stages occur concurrently. For example, one hair may be in anagen phase while another is in telogen or catagen phase.
- Anagen phase: this is the phase of active hair growth. In this phase, cells in the root of the hair in the hair follicle divide rapidly. This cell division results in the hair shaft growing about 1cm (~ half an inch) every month. A single hair can stay in this phase from 2-7 years, but the actual length is does so is genetically determined. At any given point, roughly 85-90% of hair is in this phase.
Tip: The key to achieving hair length is making sure your hair stays in this phase for as long as is possible.
- Catagen phase: this is the transitional phase that lasts about ten days. During this stage, the hair follicle decreases in size and detaches from the dermal papilla. It
- Telogen phase: During telogen, the resting hair remains in the follicle until it is pushed out by the growth of a new anagen hair. The telogen phase is the resting phase of the hair follicle. At any given time, 10 to 15 percent of all hairs are in the telogen phase. This phase lasts for about 100 days for hairs on the scalp and much longer for hairs on the eyebrow, eyelash, arm and leg.
Anything that disrupts the hair growth cycle can cause hair to prematurely enter the telogen phase. This later results in excessive shedding, known as telogen effluvium.
Examples of disruptions that can cause telogen effluvium include, but are not limited to the following:
- Sudden or extreme weight loss
- Severe emotional stress
- Severe illness
- Thyroid disorder
It’s important to note that the hair follicle can easily get of out the resting phase once the disruption is corrected, except when the disruption is a thyroid disorder. Thyroid disorder makes the follicle stay in telogen phase for much longer.
Tip: It goes without saying that it’s vital to take care of your emotional wellbeing. Stress releases the hormone cortisol into your blood stream, and if high levels of this hormone are sustained in the body for too long, cell regeneration is affected. This affects the anagen phase of the hair cycle.
Exogen phase: This is a part of the resting phase where the old hair detaches and sheds, and new hair continues to grow. Approximately 50 to 150 of your hairs may fall out daily. That is considered a normal rate of hair shedding. While this phase is happening, the hair follicle is already in anagen phase, making new hair cells.
It’s a lot of information to take in, but it’s information worth knowing if healthy hair is the ultimate goal.
May your Afro grow and your skin glow as you flow though life.